Prius 12V Battery Replacement and the Ice Pick

by Ben N on January 24, 2016


I like ice – in a glass with a drink.

So, when it was time to replace the 12V battery in our Prius, I wan’t pleased to see it frozen in place, encased in a block of solid ice….

Recently, we’ve had a spell of extra cold weather – multiple days of 0 degrees Fahrenheit, with 15 to 20 below windchills. One of those mornings, I got a panicked call from my wife – trapped at the grocery store because the Prius wouldn’t start. I ended up driving over there in the Mitsubishi iMiEV electric car and brought my jumper cables. Sure enough, the Prius was as dead as a door-nail. The dome lights wouldn’t come on, no signs of life whatsoever.

When it’s that cold, jumper cables don’t uncurl – they just stay frozen in whatever coiled up shape they were in. Likewise, it’s ill-advisable to be outdoors without thick gloves, yet the tiny plastic hooks that hold the fuse box cover on cannot be undone with hands so encumbered. (I heard once that everything on the exterior of the Space Shuttles and the Space Station is very large and easy to grasp, so that astronauts in their bulky space-suits can still fix things.)

IMG_7437Long story short, I got the Prius started, although it took a while and I was not very comfortable. Even after I got it started, I still had to clear out all the error codes and reset the computer. Why the car started OK at the house but NOT later at the grocery store, I’ll never know. The only thing that I could think of is that the car was more exposed to the wind at the store.

So, I decided it was time for a new battery. I really wanted to get something better than a stock battery, and I had heard that Optima designed a battery just for the Prius. I had always been very happy with the YellowTops I put in my motorcycle, so I decided I’d get the small Optima for the Prius. I checked online and saw that the local auto parts store had one in stock….. for $230! Sounded a little pricy to me.

I checked some other sources and eventually found that I could get the same battery on WITH, here’s the kicker, FREE shipping, for $150.

I figured that I wanted the weather to warm up a little before I changed the battery. I cold wait two days for the battery to show up, and the weather to warm.

So that’s why I was out in my driveway today. Time to swap out for the new battery.

In a Prius, the battery is in the far back right corner. Basically, it’s in the trunk, instead of under the hood. I figured that may have contributed to why it didn’t work. Not only was it cold, but it didn’t even get any heat when the engine was running!

IMG_7483I cleared out the trunk, folded back the cover, removed the right-rear panel that covers the battery, and got to work. To start with, the top of the battery is covered with several electrical connections that go to a few small fuses right on the battery. I unplugged those. Next was removing a plastic vent that goes over the battery. One bolt screwed that to the bottom of the car. This car is modified with an aftermarket additional lithium battery (A Hymotion L-5 Plug-in System.) Unfortunately, it just made it a little harder to get to this bolt. I had several socket extensions, and I was able to get the 10mm socket down between the Hymotion and the vent. After removing the other bolt that holds the plastic vent tube in place, I removed the vent as well.

IMG_7481With the unnecessaries out of the way, I could finally see what the problem with the battery was. It was embedded in a block of ice. OK, well, not completely covered, but it WAS sitting in a layer of ice a good two inches thick. It looked as though someone poured about a half-gallon of water around the battery, and let it freeze.

There was NO WAY that I was simply going to lift the battery out. I fetched my trouble light, 1500 watt heat gun, and an extension cord. I started experimenting with melting the ice with the heat gun. Once some started to melt, I had to figure out how to get the water out. I couldn’t really get a towel or something else absorbent easily in there. I did find a piece of vinyl tubing. After a quick check of the water to make sure that it WAS water and not battery acid or some other number or horrible liquids, I sucked on the tubing, slurping the ice-water out and spitting it into a cup. I also have a pry-bar which is a hook on one end and comes to a point on the other. I can never remember the name of this particular tool, but it sure is handy for a lot of things, including use as a large ice pick. I stabbed at the ice, chipping away with the spike, the heat gun blazing in my other hand.

IMG_7494Heat, stab, slurp, spit. Not what I usually imagine myself doing in a typical car repair.

Once enough of the ice was gone, I was able to completely disconnect the battery, release the tie-down, and pry the battery loose. With the battery removed, I had more room to work. Eventually, I was even able to get at the bolts that hold in the battery bracket. I removed that as well.

I thought it was odd that this well in the corner of the car was pretty much the lowest place of the interior of the car, yet it didn’t have a drain plug. Any time I ever looked in the spare tire well on a car, there was always a rubber plug in the bottom that could be pulled to drain the car if water got inside.

IMG_7491_w_textI looked from the bottom of the car, but couldn’t get a great view without putting it up on a jack. I felt with my hands under the car. I cold feel something rubbery, that was about the right size for a drain plug, but I couldn’t pull it out. After I had everything else removed from the battery compartment, I finally found the drain plug – which was still coated in ice. After further heat-gunning, I was finally able to pull it and drain the rest of the water.

Battery_Vent_System1How did all this ice get in by the battery!?! I have no real idea, but I do have a theory: There’s no insulation around the battery, it’s just bare car sheet metal. On the right hand side of the back seat, there’s an air vent. This takes passenger compartment air and blows it through the High Voltage battery pack, to help keep it cool in the summer and warm in the winter. The air then goes through the output vent and exits the car right near the 12V battery. Also, that vent has a large hole in it near the battery. I’m not sure why, but I think it’s so that the 12V battery also gets some temperature conditioning. However, since it’s been so cold, I don’t think there was any reasonable amount of heat going on in the car. So, cold air would go through the battery venting, come out by the very cold corner near the 12V battery and when the air hit the very cold sheet metal, the moisture would condense out and drip to the bottom, around the battery, then freeze.

IMG_7493With everything else out of the way, installing the 12V Optima YellowTop battery was pretty straight-forward. I put it in, made all the electrical connections, bolted down the battery tie-down strap, and reinstalled the piece of plastic air-vent.

We used the Prius to go visit relatives this afternoon, and everything worked just fine.

What’s to keep this ice build-up from happening again? Not much, BUT I did leave OUT the rubber plug in the bottom of the battery well. Hopefully, this should at least allow condensation to drip out. I’ll still need to come up with some sort of solution to keep this from happening again. Although part of the problem was that the battery was old, I’m not sure how well even a YellowTop will do while encased in ice.

Perhaps I could insulate the battery – wrap in in radiant barrier? Fill the void with Great Stuff? Add 120V heat tape down around the battery? Who knows! Maybe you have a good idea about how all the ice got down by the battery, and how to keep it from happening again. If you do, let me know!

Til next time, stay charged up!


Electric Car Heater Thermal Imaging

by Ben N on January 17, 2016

Lately, it’s been cold – which has me thinking quite a bit about electric cars and HEAT. I realized that I own a thermal camera, so maybe it was time to go into the world of VISUALIZING heat in an electric car!

My Mitsubishi iMiEV is a bit of an oddball when it comes to heating. The car maintains a liquid-based heating system as a heritage from the gasoline car it was based on. Instead of an engine, an electric heating element heats the fluid, which is passed to a heater core, where a fan blows the air into the passenger compartment. It’s not very efficient, and it takes a while to warm up.

I broke out my thermal camera and mounted it to the top of my video camera to be able to shoot both visible wavelength video AND thermal video at the same time.

To start with it was just over 0 degrees Farenheit – plenty cold enough in my book. It was a sunny day, and since the colors of the thermal images are all relative, even the dark parts of the car show up as warmer, as they soak up the sunlight.

IMG_7400Unfortunately, the coolant reservoir was the coldest thing under the hood! I set the car to run with the pre-heater, which warms up the car using electricity straight from the wall instead of the battery pack. I returned ten minutes later to see that the coolant reservoir was now the WARMEST thing under the hood. Also in the thermal video, I could clearly see the heater hoses running to and from the reservoir. What this really means is that a fair amount of heat is ESCAPING from there, and those hoses and the tank itself really should be insulated.

Inside the car, it was interesting to see what the 12V electric blanket looked like. The heated blanket has been working very well – it warms up fast and only uses 40 watts. That’s efficient use of energy and puts the heat where you want it – on the human, instead of just heating up the entire inside of the car.

The defroster also activates the heated side mirrors. They were at 70 degrees. The mirrors easily melt off snow and ice.

The heated driver’s seat was fun too see in thermal imaging too. The electric “butt-warmer” looks like a toaster element!


On the back of the car, the electric defroster on the rear window really lights up on the thermal image.

So what doesn’t get warm? The footwell. If I direct all the heat to my feet while driving, I get SOME heat there, but then the windshield and windows start to fog up. If I split the airflow between the defrost and heat modes, I simply don’t get enough heat to my feet. So far, cold toes have been the single biggest disadvantage to this car. (Of course, that wouldn’t be a problem in the summer, or a warmer state, like Florida…)

After quite a lot of reading on the MyiMiEV forum, I’ve decided that I want to add a “parking heater”. That is a coolant heater that runs on liquid fuel – usually diesel or gasoline. I’ve already ordered a 5KW heater designed to run on gasoline. I plan to run it on E85 or straight ethanol. It will be a few weeks until I get the heater delivered and installed, but when I do, I’ll make sure to take photos and videos!

Till next time, stay warm and charged up!



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Too Cold for EVs?

by Ben N on January 14, 2016


After a strange, warm, “El-Nino” start to the winter, temperatures have suddenly plummeted. Which begs the question – How cold is TOO cold for an EV?

I bought my Mitsubishi iMiEV electric car on the day of the first snow-storm of this winter. Other than that, we had unusually warm weather all the way past Christmas. Until just recently, when temperatures dropped.

This Monday, the thermometer said NEGATIVE 8 °F when I woke up. I was working that day at a location 23 miles away. The Mitsubishi has the shortest official range of any battery-electric car in the United States at 62 miles. But the government testing rates cars under TEST conditions, NOT Wisconsin winters! Batteries don’t perform as well when cold, and having snow on the road means more energy used to turn the wheels, further reducing range.

IMG_7389The other big issue with this particular car is that is has a rather poor heater. Other than using electricity to create heat, the iMiEV otherwise has a heating system identical to any ICE (Internal Combustion Engine) vehicle! A heater fluid (we would normally call it coolant, but in this case it’s not used for cooling at all) travels through uninsulated hoses from the electric heater to a heater core, where a fan then blows air into the passenger compartment. The heater also produces a lower TEMPERATURE than most ICE heating systems. So, even when it’s working full blast, there’s still not as much heat as a person might be used to in another vehicle. And, due to the fact that it’s a liquid-based system there’s still always a warm-up time. You could drive for half an hour with the heat off, and when you want to turn it on, it STILL has to warm up.

The heater can also draw up to 5,000 watts. That translates to over 6 HP. In typical driving, the heater can use a quarter to one-third of the total energy of the car – decreasing range by that amount. In bumper to bumper traffic, or while stopped, the heater can actually use as much or MORE energy as the motor!

So, when I left for work on Monday morning, I used the heater as little as I could, and drove at very reasonable speeds. When I got to the work location, my battery charge was down to just below half. If I drove the same on the way home from work as I did to get there, I wouldn’t have enough energy to make it! Fortunately, I had two options. One was to simply take a different route. By taking back-roads, I could drive slower. Driving slower really helps increase range. The other thing is that I did have access to a 120V outdoor electric outlet at this location. I rolled out my extension cord and plugged-in the car using my “Level 1″ charger.

When I was ready to leave, I did have some additional battery charge, but not as much as I had hoped. Level 1 charging is significantly slower than level 2, and I think the cold was limiting my rate of charge as well. At least the battery was now in the upper half of the charge range. I still had to work another job for the evening. By that time, it was also dark, it was turning into rush hour traffic, AND it started snowing.

IMG_6539One of the reasons why I bought this car is that it has a “Quick Charge” port. Using the CHAdeMO charging system, the car can be recharged to 80% in 30 minutes. There’s only one CHAdeMO charger in my area, but it’s free, and conveniently located just off the main east/west freeway in the area. While I could make it home, driving slowly and leaving the heat off, I thought it would be nicer to have some more battery charge so that I could use the heat and drive at what speed and route I would like – just like any gas car would.

I turned the heat on to warm up and headed to Marshall Autobody in Waukesha, Wisconsin to use the Quick Charger. It was a little out of the way, but I would more than make that up when I charged.

After I arrived, I plugged in the charger and ……   Nothing happened.
Hmmm. I thought I was doing it right. Press the button on the screen, plug in, make sure that red emergency-stop button is reset…. Nope, it just didn’t work.

Only a few moments after I arrived, another iMiEV pulled up. This was pretty strange, as I had never run into another one in the wild yet. I said hello, and taking a wild guess, asked “Does your name happen to be Barb?” In fact, it was Barb. I had seen her name on an electric car group list, and there’s just not that many iMiEVs out there. We weren’t able to get the CHAdeMO to work with her car either. Likely, it was some sort of an issue due to the cold weather.

I did notice that in Barb’s car, she had a fuzzy steering wheel cover and a lap blanket. Unlike mine, hers was just a plain blanket, not an electric one. Just like me, she was bundled up in the type of clothing one would expect to see on somebody spending hours outside in the extreme cold. I recently upgraded my headlights to LED. Barb’s car still had the stock halogens, so I used the opportunity to snap a photo comparing the two.


Barb left, and was traveling the opposite direction as I, so she was hoping to be able to make it another CHAdeMO station off to the southeast. I plugged my car into the J1772 Level 2 charger, which worked great, for a short while while I reported the faulty CHAdeMO to the owners and posted a comment to PlugShare. Elaine from Marshall was already outside on the phone with a tech before I even left.

Back on the road, it continued snowing. I ended up at a net LOSS of energy trying to get a quick charge. The location was a few miles out of my way, and I was running the heat while driving over there. To make up for it, I took the side roads. Due to the snow, all traffic was much slower, which was good for my range.

After I arrived at the other place I would be working that day – a municipal building – I parked at the Library. There are outside 120V electric outlets there. While I would only be there for about an hour and a half, I figured any energy I could get would be good. I parked at the last space in front of the Library and ran my extension cord across the sidewalk. Because it WAS the last space, I figured there would be little, if any, foot traffic over my extension cord. In the future, I intend to carry an outdoor rug that I can place over the extension cord, preventing the trip hazard. The last thing I need is for librarians to be mad at me!

When I was ready to leave, the car was still plugged in, and there were no hate notes or lawsuits. Additional range was minimal. I again took the side roads and finally headed home. Once I was about 3 miles from home and saw that I would still have plenty of battery to make it the rest of the way, only then did I turn the heat back on. Getting home was otherwise uneventful. Once there, I parked, plugged the car in, and said good-night.

During my journey that day, most of my body was a pretty good temperature. However, my toes were COLD! After stepping around in the snow trying to get an unsuccessful quick charge, my footwear was then wet, and my toes were PAINFULLY cold. The electric lap blanket works well. Everyone should have one in their car, it’s pure luxury! However, it doesn’t cover my toes, as I need those for operating the vehicle. Likewise, my really good winter boots are large enough that I don’t trust NOT hitting the brake and accelerator at the same time with them. Even if my entire body is covered with arctic gear, I still need the heat to run the defroster – simply for visibility.

IMG_7390The next day,I upgraded my windshield washer fluid. So much salt gets used on the roads in my area that windshields get caked with dried salt streaks. When I would use the washer fluid, it would just freeze right to the windshield! In a car with a nice HOT defroster, it might not be an issue. I stopped at the auto parts store and was glad to see that the fluid rated for down to -25°F was on sale. I drained the blue fluid and poured the orange fluid in it’s place. When I had stopped at a gas station earlier to use their squeegee, the purple washer fluid in the bucket was frozen into a grape slush. So far, the orange washer fluid seems to be working well.

Now don’t let me get TOO down on the heating system in the car! The driver’s seat is heated, and works great! The car also has a “pre-heat” system that works pretty well. If the car is plugged in to wall power (which it usually is from charging the night before) a press of a button on the remote turns on the heat, and gets its power from the wall, instead of the battery, so I can leave with NOT only a full battery pack, but a warm car as well!

So, on a short winter trip, the car can be preheated and the heater can run the whole time. It works great AND doesn’t use a single drop of gasoline. Win/Win for everyone. BUT, a longer trip means serious compromises with comfort, just to make the car still go the distance I need it too. Not so fun!

Now keep in mind that it’s the combination of a small battery and sub-par heater that makes it so tough. For example, a Nissan LEAF has a larger battery pack, all seats are heated, and at least some of those cars have heated steering wheels. The LEAF also has improved insulation vs other Nissan cars. (The iMiEV appears to be completely uninsulated!) The newer LEAFs use a more efficient heat-pump system instead of resistive heating. While I have heard of complaints by LEAF owners of the shorter winter range, I haven’t heard of it being nearly the issue that it is with the Mitsubishi iMiEVs.

So, I am considering a “Parking Heater”. That is a liquid-fueled heater that heats the engine coolant, so that a car can have its engine and heating system warmed up WITHOUT running its engine or using an electric block heater. There are also air-to-air versions which just directly heat air for the passenger compartment. They are popular on semi-trucks with sleeper cabs, so that the driver can stay warm without idling a 500 horsepower engine.

Several iMiEV owners in cold climates (Canada, Finland, Russia, even New Jersey,) have successfully installed these heaters with fantastic results. My “knee-jerk” reaction to the thought of adding fossil fuel to an EV was “No WAY! You aren’t gonna put petroleum in MY renewably-powered electric car!” But after reading through some forum threads, it actually makes a lot of sense. Here’s why – it’s APPROPRIATE use of fuel. The problem with most internal combustion engines is that they are SO inefficient that heat is the majority waste product. Every car needs a large radiator just to keep the vehicle from overheating! Of course, in the winter, some of that “waste heat energy” can be directed to defrosting a windshield or keeping feet warm.

5KW-12V-font-b-Diesel-b-font-Liquid-Parking-Heater-webasto-Eberspaecher-water-heater-RV-heaterLiquid fuels are GREAT for creating heat.

Using a small, efficient, PURPOSE BUILT device to only create heat frees up the battery system to maximize energy for travel. Since there’s a reduced load on the battery, battery cycles are also reduced and battery LIFE is also extended.

Also, nothing says that I have to use petroleum in the heater. Bio-diesel, E85, and straight ethanol all have potential use in such a system. A friend of mine brews his own ethanol from scratch (yes, he has the ATF license!) I’m sure I could get a few gallons per year of automotive moonshine from him.

The heater would be plumbed in such a way that electric heater and electric pre-heat feature would still work properly. The finished system would in fact be a Hybrid Heating System on an Electric Car.

So, now my only real question is whether I want to purchase the diesel or gasoline version of the heater. I’m leaning towards gasoline, as it’s easier to get ethanol than bio-diesel in my area. Even if I DO use petroleum, and it lets me use the electric car, where I would otherwise need to use a fossil-fuel powered car, it’s still a significant net cost and carbon savings!

And, on the upside, as I write this the sun has finally come out and temperature has warmed up into the 20′s.

‘Til next time, stay warm and charged-up!

PS: One feature that I really haven’t been thinking about is the heated side mirrors. I have had ZERO issues with ice or snow on the side mirrors. The mirror defrosters work so well, I just don’t thing about it. They work great!


LED Headlights

by Ben N on January 8, 2016


Recently, I did a few small LED lighting upgrades to my electric car. Those went well, so I thought I would tackle the big one: Installing LED DRIVING LIGHTS!

And I thought it would be easy….

The car has separate bulbs for the low beam, high beam, and parking light. My plan was to upgrade the low beam and parking lights with equivalent LEDs.

The Mitsubishi iMiEV is a very likable little car, but it has a few short-comings. One of them is that if you look up in the user manual how to change a headlamp, it simply states “Please take to Dealer.”

The reason why is that the lights are so packed in the corners that there is no way to simply get to the bulb itself. Instead, I had to remove the entire headlight assembly to get to the bulb. And is it easy to take out the headlight assembly? Well, while it’s POSSIBLE to get it out by only removing  a few fasteners and bending back the bumper cover to get at all the bolts, the official procedure includes removing what appears to be the entire front of the car…

IMG_7311Even then, there’s a little plastic hook at the top of the light, NOT MENTIONED ANYWHERE IN THE SERVICE MANUAL, which prevents a person from removing the headlight without a particular arcane technique of pushing, pulling, and lifting the headlight, all at the same time. I did happen to get ONE of the two headlights out WITHOUT breaking off the plastic hook. Since there appears to be no function to this hook, other than to get you to pay dealer prices to have a new headlight put in, it really wasn’t a loss.

I started on the driver’s side. Once the headlight assembly was out, things became much more straight-forward. The low beam has a projection lens. I unscrewed the cap on the back of the low beam section, then unplugged the bulb, turned it counter-clockwise, and removed it. I mail ordered the LED headlight bulbs. They were $70, including shipping. They were Sirius LED brand, featuring CREE components – two LEDs, one pointing up, one pointing down. The bulbs have built-in cooling fans, and are considered “plug-and-play”.

IMG_7313The replacement LED bulb looks HUGE in comparison to the original halogen bulb. Fortunately, there’s plenty of space inside the low beam housing. The trickiest part was the fact that the short wiring pig-tail on the LED bulb came out at a right angle and was very stiff. I had to tuck in the tail first to be able to get the LED bulb in at all. Once it was in, I could then pull the pig tail out and plug it in to the wiring harness. With that, I screwed the cover back on.

I also wanted to upgrade the parking light. This is a very small bulb below and to the side of the projection low beam. It uses a 5W5 bulb, which is also what the license plate lights and marker lights on this car uses. I found that I could get a WHOLE BAG of these bulbs for cheap, so I ordered them, knowing I could use them all around the car. ( )

LED bulb for parking light.

I removed the original 5W5 bulb by rotating the holder counter clockwise and pulling it out. I removed the bulb and then inserted the LED version.

Next, I set the headlight assembly back roughly in place, and reconnected the wire harness, so that I could test the lights. I turned the lights on and was pleased by the instant bright light from the low beam, but the parking light DIDN’T come on!

I removed it from the housing, this time letting the bulb hang on the wire, but outside the housing, for more easy access and testing. Figuring that LEDs are DC electronics, where polarity can be important, I SPUN the bulb 180 degrees, and then turn the lights back on. Nothing! It still didn’t light. Did I perhaps pinch a wire or cause a short? I put the original bulb back in. That lit up just fine.

So, did I have a bad LED bulb? I took the LED over to a known good power supply (a 12V battery in my Elec-Trak E15 electric lawn tractor) and connected it with two jumper wires. It didn’t light up. I swapped the wires to reverse the polarity. LIGHT! So, the LED bulb DOES work, but it also DOES have a particular polarity, it just doesn’t work when I plug it in to the car!?!? I examined the bulb and realized that the two wires coming out of it are rather thin. They are also not glued or otherwise held in a very particular position. It looked like when I installed the bulb, one of the wires would naturally bend AWAY from the conductor in the socket in the car. I simply gave a slight bend to the wire to center it and make sure it would make good contact, then put it back in. With a flick of the car’s light switch, the bulb came right on.

Tool for removing side marker light. I used a plastic bike tire tool.

I also wanted to replace the side marker light with the same W5W LED bulbs. The side marker light on the car can be replaced by sliding the assembly toward the front of the car (to the left in the photo) to compress a springy plastic part on the front, and unhook the back. With the light out, I unplugged the wire harness, removed the bulb from the holder, and put in the LED bulb. When I went to put the bulb back in the light housing, it wouldn’t fit! Similar to trying to get the LED in the Daytime Running Light, the bulb just wouldn’t go all the way in! This time, it was the actual length of the LED bulb itself. Inside the housing, the LED would hit the plastic lens BEFORE the base could engage and lock in place. I wouldn’t be able to use these LED bulbs in the side marker lights. I put the original bulb back in and clipped the housing back in place in the side of the car.

On the passenger side of the car, I got ready to remove the entire bumper cover. On the driver side, I had only removed enough fasteners to get the bumper cover out of the general area of the headlight and get access to all three bolts. Since that side was already loose, and I would have to at LEAST to the same on the passenger side, I figured that I may as well remove the entire bumper cover. It’s not too difficult, but it’s a fair number of fasteners to remove. I didn’t bother to remove the fasteners at the very bottom of the front of both wheel wells. This let me get the bumper cover completely out of the way, yet without having to drop it on the ground.

IMG_7310Finally, I removed the three bolts holding in the headlight assembly. Only that stupid little plastic hook kept the light in place. I moved the light in different directions, to see how it would effect the hook, yet none of them released it. Finally, I managed to figure it out, and I pulled the headlight free WITHOUT breaking the hook. I believe that I pushed the headlamp all the way back, pushed down on the front, and then lifted on the back. Likely, I will never be able to repeat this feat.

I replaced the driving light low beam with the LED. This one didn’t feel like it fit as well. Twisting the bulb into place, it didn’t seem to have as much resistance against the gasket at the first bulb did. I’ll have to keep an eye on this bulb and make sure that vibration doesn’t cause it to rotate by itself.

As for the running light bulb, I made sure to pre-bend the wires on the LED so that they would make good contact in the socket. I then tested the lights, and when that bulb didn’t come on, I spun it. With the new polarity, the bulb came right on.

After testing to see that all the lights were working properly, I fully reinstalled both headlights, tightening down all three bolts on each. When I went to pull the bumper cover back in place, I could NOT get it to go back on. I tugged and pried and tried to see what was catching. It turns out that there’s three fasteners right in the middle of the bumper cover that stick into the steel bumper itself. The middle one is a spike of plastic that needs to exactly go back into a hole. With the bottom of the bumper cover still fastened, I couldn’t get the angle to make it line back up. Instead, I would have to remove the few remaining fasteners on the very bottom of the bumper cover, disconnect the wiring harness to the Fog Lights (which are built in to the bumper cover), and remove the whole thing to be able to properly re-install it!

At that point, the entire front of my car looked like it was missing, all just to replace a few light bulbs!

Wowza. All this just to change a light bulb!

I wrestled the cover back on, aligning the center plastic pin back into its hole in the bumper and then replacing the myriad of fasteners to completely reinstall the cover.

Finally, my car was all back together.

I turned on the headlights so that I could get a couple of photos showing the complete LED upgrade. That’s when I saw that they didn’t all work. The passenger daytime running light was out. The driver side marker light was out. When I tested the turn signals, the right turn signal was out and the right-rear signal blinked twice as fast as it should have!

And I just spent the last 20 minutes putting every last screw and fastener in!

I went back inside the house to warm up, get some dinner, and take a break from the project.

Afterwards, I had decided that perhaps this wasn’t such a big job to fix the non-working lights. I had an idea as to what might cause all these problems. I removed the fasteners from the passenger side fender liner, to get at the back of the passenger side fog-light assembly. Sure enough. It wasn’t plugged in. I had to unplug it to fully remove the bumper cover. When I put the cover back on, I hadn’t inserting the electrical connector far enough for it to click in place, and it had come back out. I plugged it in fully, then tested the lights. The Daytime Running light worked again, as did the turn signal. The side marker light was still out.

I figured that the side marker was probably just a bad connection. I removed it, inspected the bulb, pulled it out, put it back in made sure the wiring connection was solid, and put it all back together. Worked fine after that.

What my driveway looks like the LED headlights on it.

So, it turned out that it’s not exactly an easy job to replace a light bulb in this car! Overall, I really like the look! The “cool blue” LED color makes the white body color look even brighter and the car is more visible than ever before, but how well do the headlights work? I took a short night ride out to a local store (I needed to buy coffee anyways…)

The shape of the projection of the LED headlights looks VERY similar to that of the original halogen bulbs. I was glad to see that, as it was my primary concern. It seems like the single biggest issue right now with upgrading headlights to LED is that the reflectors are designed to work with bulbs of a very particular size and shape. By their nature, LED bulbs are simply NOT the same size and shape as the halogen. So, there’s big possibility that the reflectors will simply NOT reflect the light the way they were intended. I was pleased to see that these bulbs appeared to work well with the projection lenses and reflectors.

LED driving lights and LED parking lights.

As for the BRIGHTNESS of the headlights, it’s hard to say. The bulbs are RATED at 2000 lumens. That SHOULD be brighter than the typical 1400 lumens of an average H11 bulb. But it didn’t LOOK like it was! The eye also perceives the intensity of different colors of light differently. Due to the complexity of the headlight installation, I wasn’t able to simply put in ONE LED headlight and drive around comparing the light from one side of the car with the other. After I had the first LED bulb in, I did just look at both bulbs (one halogen and one LED) and they looked very similar, other than color.

One of each, side by side. Subjectively they look equally bright.

There was also a very light rain. It seems to me that all headlights are darker when it’s raining out.

Besides that, I was mostly driving in town, where there are streetlights, many of which are now also LED, or least more of a “daylight” color. That might also have been skewing my subjective comparison.

One thing I did notice is that reflective objects at a distance (street signs, reflectors on mailboxes, etc.) seemed to show up better with the LEDs than the original halogen lights. I think the LEDs may also light up just a little better to the SIDES of the car – a benefit to spotting deer trying to cross the road at night.

Again, all of this is based on one short ride into town at night in a light rain. I’ll have to do some more driving to give a really fair comparison.

Take a look through all of my photos and see for yourself.

Till next time, stay charged up!



LED Daytime Running Lights

by Ben N on January 7, 2016

LED bulb temporarily installed, but not fully in place in the reflector.

Seeing how nice the LED dome lights work on the Mitsubishi iMiEV electric car, I wanted to tackle converting the rest of the lights to LED. Up next would be the daytime running lights.

The Daytime Running Lights (DRLs) are a natural choice, as they are on pretty much all the time that the car is on. So, converting from incandescent to LED should save some energy. More importantly, it looks cool and adds visibility! (I did do the math on energy savings of the LED license plate bulbs. Theoretically, they can save 13 cents of electricity per year, or help drive the car four miles further, annually.)

The DLRs on this car are bulbs that mount inside the foglight assembly. They stick up on an angle, with a smaller reflector behind. Behind that is the larger reflector and halogen bulb of the much more powerful fog-light.


I ordered a pair of “corncob” LED bulbs from the internets. These cost me $8.85 for the pair and are designed for 2011/2012 Cameros. ( )

To get to the light on the iMiEV, I would need to remove the plastic fender liner. I turned the steering wheel all the way to one side. Because the car has such skinny front tires, it wasn’t necessary to remove the front wheel to get in through the wheel well. The finder liner is held on at the bottom by two 10mm bolts on the very bottom edge, and a number of phillips screws running through plastic inserts. I removed the two bolts and six screws. That let me pull back the plastic fender liner. The liner was still held to the car by screws in the middle and back of the wheel well, but I could get at the light.


Looking inside, I could see the light assembly and the plugs going to the DRL bulb and above it, the fog light bulb. There’s also a geared mechanism for adjusting the foglight. (Which is accessible from the outside by sticking a tool through the small hole near the light.)

I unplugged the DRL bulb, then rotated the bulb counter-clockwise and pulled it out. The bulb itself is short and round. Physically comparing the incandescent and LED bulbs, it was easy to see that the LED bulb was longer.

I then took the LED bulb and inserted it into the housing. However, it would EXACTLY not go in all the way! Was the length of the bulb preventing it from being fully inserted? No, looking into the housing from the outside, I could see there was plenty of room. So what was different?

IMG_7264I pulled the bulb out, then compared the two bulbs side by side for minor differences. The one that I could see was that there is a black plastic “collar” that comes up on the LED bulb HIGHER than it does on the traditional bulb. In the photo on the left, compare how much black plastic there is to the left of the red o-ring on the two bulbs. It looked like the extra long plastic on the LED bulb was just barely striking the silver reflector, preventing it from being inserted all the way.

Rather than completely removing the entire lighting assembly, taking out the inner reflector, modifying it, and reinstalling it, it seemed easier to hack the $4 light bulb!

I got out my Dremel tool and put in a cut-off disc. I then scored a line around the plastic collar and made multiple passes until it was cut nearly all the way through. Then I inserted a flat screwdriver into the cut and twisted, to pop the ring of excess material free. I pulled off the ring and cleaned up any burrs of plastic.


Next, I put the LED bulb into the fixture, pushed it all the way in, and twisted. It fit!

I plugged in the power cable, then turned on the car to see the difference between the side with the incandescent bulb, and the side with the LED bulb. The LED bulb was clearly brighter. It’s also a better color. This is the “cool” LED color, which looks more like daylight. To me, it looks much more modern. The little iMiEV is starting to get Sci-Fi Lighting, instead of the dull orange lighting of yesteryear.


After that, I did the same upgrade on the other DRL.

So, what have we learned? Unfortunately, there are still LED bulbs that are NOT exactly plug-and play. The dome lights and license plate lights both popped right in as direct replacements. For the DRLs? Not so much. Still, once I figured out what I needed to do, it was a pretty simple modification for a handy guy with the right tools.

We are also seeing so many more new cars coming to market with complete LED and/or HID lighting packages on them. Besides saving energy, they also have great visibility and mean you may NEVER have to replace a lightbulb in your car ever again!

Until next time, stay charged up!