2003 C240 Headlights Not Working
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C240
2003 C240 Headlights Not Working
I have a question about the headlights not working on a 2003 C240. None of the headlights (high or low) work. The left side was working and the right side would work intermittently. Now neither side works. I have replaced the headlight switch and that did not work. The running lights, marker lights, brake lights and signals work fine. I ended up hard wiring the low beam headlights to the fuse box to get them working and they work fine now, but that is just a work around until I can figure out why the headlights don't work normally. With the lights hard wired, the lights activate when the ignition switch is turned to the on position. There is no need to turn the headlight switch to the on position.
Before hard wiring the headlights I noticed that both headlights would come on when the engine was turning over, but would go out as soon as the engine fired up. I thought that was odd.
Something else that is odd. After hard wiring the low beam headlights and with the headlight switch in the on position, the headlights will pulse every 6 seconds and there is a slight drop in engine revs. This is consistent. If the headlight switch is off or in the running light position the lights do not pulse every 6 seconds. The lights stay steady.
Any assistance would be greatly appreciated.
Thanks,
Caracal
Before hard wiring the headlights I noticed that both headlights would come on when the engine was turning over, but would go out as soon as the engine fired up. I thought that was odd.
Something else that is odd. After hard wiring the low beam headlights and with the headlight switch in the on position, the headlights will pulse every 6 seconds and there is a slight drop in engine revs. This is consistent. If the headlight switch is off or in the running light position the lights do not pulse every 6 seconds. The lights stay steady.
Any assistance would be greatly appreciated.
Thanks,
Caracal
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Joined: Dec 2003
Posts: 3,275
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From: BC, Canada
2003 C230K Coupe Orion Blue
I'd look into the front SAM. I'm thinking something on the PCB is cooked.
Also I'd check my headlight relays. The car often uses the same relay model for several different circuits. If this is the case, you can swap 2 relays of the same type and see if the problem shifts to the other circuit.
Also I'd check my headlight relays. The car often uses the same relay model for several different circuits. If this is the case, you can swap 2 relays of the same type and see if the problem shifts to the other circuit.
