aframe

My headlights will not stay on. They are good at first and then after a bit they will go out and i have to turn them off and back on and that only works part of the time.......i have done my best to search the forums for an answer and havent found one so i thought i would just ask and hop somebody can tell me what the problem is is which relay is the headlight relay any help would be appreciated i have an 03 gt

petrock

Sounds like you have a loose connection or partially broken wire somewhere. I’d get the factory service manual, or an account at alldatadiy.com to get the circuit diagrams. Start poking around with a volt-meter while wiggling the wires around to find the break or loose connection. Good luck...

cliffyk

The headlamp wiring is very straightforward, there is no relay just fuses and two switches, the main light switch and the multifunction switch:



Check the fuses first, then when the lights go out does turning on the high beams do anything? If not then I would investigate the main switch...

petrock

If it was a blown fuse then the light wouldn’t work at all. Since it is intermittent then it is either a switch, connector or wire. My bet is on the main light switch, or its connector, since it comes back on (for a short time at least) after turning the lights off/on again. Good luck…

cliffyk

Vibration can, over time and sometimes, make fuses intermittent, it is not common but it does happen and often manifests itself in circuits that work for a while and then cut-out.

Check the fuses first. Actually I would just replace them all to ensure the power supply was good...

aframe

When i turn the high beams on they just go out there is no intermitten flashing just darkness

wcgman

Could be the switch or the stalk switch (turn signal) where you go HI-LO. I personally would start with the main switch cuz I've replaced one of those and it wasnt a hard job before trying the multifunction switch on the column. Pretty sure that thing is pricier and I'd guess it's harder to replace.

aframe

i replaced the main switch and the problem was the same so i will replace the fuses and let you guys know

petrock

Definitely check the fuses. I would have done that way before blindly throwing a new switch at the problem.

If the fuse are not blown (there are 3 in the headlight circuit), make sure they aren’t corroded either. If the pins on the fuses, or the metal socket that the fuse goes into, are corroded they won’t make good contact and it will cause strange problems.

The wiring diagram that cliffyk posted gives you all the info you need to track this issue down, assuming it is the correct wiring diagram for you year/model car. Since the problem effects both headlights simultaneously in both high & low beams, then the problem is in-between the two 10A fuses just above the lights in the diagram and the 30A fuse in the upper left corner of the diagram.

The bulbs don’t share a common ground connection, so its not a bad ground problem.

So it could be the main switch, the multifunction switch, or the wires that connect them. Its a straight forward test. Don’t unplug anything, you want it all connected. With the key on, engine off, and the main switch in the Head Light position, I would start at the 2 10A fuses for the headlights and make sure that both metal tabs on top of each of the fuse have 12 volts DC. If one tab has 12 volts and the other doesn't then the fuse is blown. If both tabs do not have 12 volts, which I suspect they will not, work your way back up the diagram. Back probe the Red/Black (RD/BK) wire with a small paper clip in the connector for the multi-function switch in the steering column. Check to see if it has 12 volts. If it does, then the Red/Black wire is broken somewhere between the multi-function switch connector and the 10A fuses. If it does not have 12 volts, then back probe & check the Red/Yellow (RD/YE) wire in the multi-function switch connector for 12 voltes. If it does, then the multi-function switch is bad and should be replaced. If it does not have 12 volts, then back probe & check the red/yellow wire in the Main switch’s connector. If it has 12 volts, then the red/yellow wire is broken between the main switch and the multifunction switch. If it doesn’t have 12 volts, then back probe & check the Dark Blue/Orange (DB/OG) wire in the main switches connector. If it has 12 volts, then the main switch is bad and should be replaced. If it does not have 12 volts, then check both metal tabs on top of the 30A fuse for the head lights. If one has 12 volts and the other does not then the fuse is blown. If both tabs do not have 12 volts, then the wire between the fuse box & battery is broken. If both tabs have 12 volts, then the Dark Green/Orange wire between the fuse box & main switch is broken.

Report back what you find. If its a broken wire, it is also fairly straight forward in finding the break. If you are getting some voltage readings below 10 volts, make sure the battery is charged. If it is, then you have excessive resistance in the circuit that can be tracked down with a series of voltage drop tests (also very straight forward). Let me know and I can write up a how-to...

Make sure to charge your battery if you have the key in the on position for more then 30 minutes. You don’t want to drain your battery while testing. However, an experienced tech should be able to do the steps I outlined above in about 20 minutes (including time to get access to the switch connectors).

Avoid poking wholes in wires. It breaks the seal around the wire and create a vector for moisture to get into the wire and corrode it from the inside out causing more electrical problems over time. You want to back probe the wires at the connector by sliding a small paperclip or safety pin or T-pin where the wire goes into the connector while the plastic connector is still plugged in. Google it if your still confused on what back probing is.

Hope that makes sense… Good luck…

aframe

After checking my fuses for a third time i finally found the problem.......it was the 10 amp fuse that was broke. I couldnt see it though cause it wasnt burnt at all and the way it broke it was still touching the other side which is why im guessing it was flickering and would work sometimes and sometimes it wouldn't......its working fine now thanks for everybody's help i hope this will help people in the future