Gem E4 2008 Headlights not working

I have a 2008 GEM E4 that the headlights stopped working. I know it’s not the bulbs. I was driving home at night and hit a bump and they went out. I have replaced the top and bottom of the two relay’s on the firewall side under the dash on the passenger side thinking it was a contact issue as I live in FL and things corrode quickly. Fuse in panel is good. Turning signals and brake lights still work.

What is odd is if I turn on the headlights, the dashboard dims and shows the Headlight icon, but the headlights don’t come on and now the turn signals and break lights don’t work, the back right tailight just turns on as a solid light and that is it. If I turn the headlight switch off, turn signals and brake lights work again.

Any idea if that would point to a short in the headlight switch itself? Anyone have that same scenario? Any help would be approeciated. Thanks.

Did you check the grounds?

Grounds where? On the head lights I only see power and common coming from the th cable in the engin compartment. The tail lights have grounds. If the Back right tail light is the one that comes on when I switch on the headlights, would that be the culprit or could it be the left tail light that is not coming on? Thanks.

This is the power going into the back of the headlights and turn signal. I don’t see a ground wire. So not clear where that would be. If i take off the tail light cover, I definitely see a green ground wire. Could a bad contact on the ground in the tail light be shorting my head lights?

This hood/headlight harness runs down and jumps to the frame harness with a little 4 pin molex. That connector is horrible for corroding, overheating and melting. Both headlights share the ground wire that goes through there.

Check that!

You can check for 12v activity when headlight switch is on, then run a separate ground maybe from the backside of the turn signal to the frame to check that.

Thanks. The turn signal and Headlights power comes from the same 4 wire molex connector in the engine compartment, (without seeing where that ground is, would the turn signals not work if the ground was faulting with a bad connection or are they on different grounds? Most of the cabling is bundled up so hard to see where it’s actually grounding. Could the ground be actually occuring back in the tail lights? I am just speculating as why I am seeing that wierd scenario where when I turn on the headlights, the turn and brakes don’t work but that back right light turns on solid? Reaching at straws here. If there is a ground for the 4 wire molex harness in the engine compartment or on the firewall side in the cab that I should be checking that you could point me to? Thx

I believe the front lights are driven totally different from the rear. There is quite a bit of magic that goes on inside the PSDM that is hidden from the users like us. Any time a power source is hunting for a ground the results can be unpredictable.

The display dimming when Headlight Sw ON is a normal function.

Many of the ground wires get stacked on top of each other and tek screwed to a bar under the dash. Make sure they are clean and tight. Headlights come out on J1. Tail lights can be found on J6.

Also- Check the plugs that come off the PSDM. They can sometimes be flaky.

Don’t forget about checking your bulbs.

How long ago was the spray coating applied?

Those look like the old style headlights which have a really shittay design for the bulb ground / common.

Thank you. I will check all the plugs and see if I can find the stacked ground line. It may take me a few days because of work. I will respond after I test. Thank you for your guidance and sharing yuor expertise.

I spray them every few years as I live at the beach and it sits outside. I checked the male/female connectors you see in the pic and they appear clean. The blinkers work. I am going to try and find where the ground wires are see if they are clean. It may take me a few days to get back to this due to work. Thanks for your feedback.

Do you have a meter?
It is probably the #1 handy item in a tool bag when working on a 15 year old e-car.
For some people #2 is a bottle of Jack.
For @JarJarJava #3 is a flamethrower.

Or at the very least,
See if you can scrounge/make up a couple jumper wires. alligator clips on the end will help quite a bit.

!2v power supply could be going out. Turn on headlights and measure voltage at he 4 pin connector


Thanks. I have a big work deliverable, so it may take me a day or two to test and respond. Thx

That appears to be the right recipe. :slight_smile:

Finally got the head lights working. Too busy with work to focus on this issue unfortunately.

After regrounding all the wires against the frame and replacing the relays, it ended up being the connection in the wiring harness that goes to the lights in the engine compartment. I was able to prove power was getting to the male connector with a volt meter but not making its way to the lights. Applying a little CLR solvent to the connectors it dissolved the corrosion and power now flows. Sitting outside at the beach, corrosion is the gremlin to most of the problems I now face. Thanks to everyone for their help and ideas.


Hope you washed the connector off with water afterwards, or at least blew it out with compressed air. CLR is blend of a few acids that don’t play nice with the aluminum, tin & copper in the wiring harness connectors & wires. The acid will also leave the leave the metal unprotected, so might be wise to invest in a tube of dielectric grease and squirt some into the connectors.

Best one shot chemical I’ve found for both removing corrosion and leaving a protective coating behind, even lubing the plastic of the connector a little bit is DeoxIT-D5

It might also be a good plan to put another plug on there. Maybe make the next one a bit more weather resistant?

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Thanks Great advice. I appreciate it.