low beam headlights

[vetteguy05]

Anybody else had problems getting their low beams to work on a C6? Mine come on in "auto" sometimes. Once they just blinked off after about 10 minutes of driving. Once in a while they just start working for no reason. Is there a loose wire or a bad ground on the fusebox that's been found before? The low beams come on every time you press the unlock button on the fob when it's dark in my garage, but then they go off when I open the door and I can't get them to come on in "auto" or even in the "on" position. :confused

 

[RC135_Tx]

This thread DRL's stopped working - Corvette Forum suggests toggling the headlamp selector on the stalk. Maybe the contacts there are not working correctly & are sometimes keeping the low beams from coming on.

Your description makes me think the light sensor is working properly. Switching to "On" manually (as you said you did) should certainly work every time, regardless of ambient light. If it was my car, I'd be betting it's a problem with the stalk.

Good luck & post whatever you find out!

 

[vetteguy05]

New findings.

This thread DRL's stopped working - Corvette Forum suggests toggling the headlamp selector on the stalk. Maybe the contacts there are not working correctly & are sometimes keeping the low beams from coming on.

Your description makes me think the light sensor is working properly. Switching to "On" manually (as you said you did) should certainly work every time, regardless of ambient light. If it was my car, I'd be betting it's a problem with the stalk.

Good luck & post whatever you find out!

I replaced the headlight switch. I recently changed the relay and the lights came on. I turned them off and drove about 15 miles and they won't come back on. The next morning I started the car and then pulled the relay out. I re-inserted it and the lights came on. Again, I drove to work, (about 15 miles) and the lights wont come on again. I took the cover off the original relay and plugged it in. If I use a rubber handled screwdriver and close what looks like a set of points, the lights come on. But when I remove it, the lights go off. Is it just that I bought a faulty relay? At least I know it's not the ballasts or the bulbs.

 

[tim414]

This thread DRL's stopped working - Corvette Forum suggests toggling the headlamp selector on the stalk. Maybe the contacts there are not working correctly & are sometimes keeping the low beams from coming on.

Your description makes me think the light sensor is working properly. Switching to "On" manually (as you said you did) should certainly work every time, regardless of ambient light. If it was my car, I'd be betting it's a problem with the stalk.

Good luck & post whatever you find out!

:iagree:

 

[tim414]

I replaced the headlight switch. I recently changed the relay and the lights came on. I turned them off and drove about 15 miles and they won't come back on. The next morning I started the car and then pulled the relay out. I re-inserted it and the lights came on. Again, I drove to work, (about 15 miles) and the lights wont come on again. I took the cover off the original relay and plugged it in. If I use a rubber handled screwdriver and close what looks like a set of points, the lights come on. But when I remove it, the lights go off. Is it just that I bought a faulty relay? At least I know it's not the ballasts or the bulbs.

Then I would look next to what part energizes the relay....

 

[RC135_Tx]

Then I would look next to what part energizes the relay....

I'm looking at the Factory Service Manual (for '06 but should be pretty similar for '05), Vol. 3, pages 8-577-579. It's a pretty involved procedure to drill down to the actual problem. I think you either need this FSM, a scan tool, & some professional (mechanical! ) help, or, preferably, both.

Wish I could be more help, but it looks like you could spend a lot of time tossing effort & parts at the problem & still not fix it. Of course, as soon as I post this, you'll post that you found the problem, no thanks to us!

-- Forgot to ask: Have any mods been done to the lighting system?

 

[vetteguy05]

I'm looking at the Factory Service Manual (for '06 but should be pretty similar for '05), Vol. 3, pages 8-577-579. It's a pretty involved procedure to drill down to the actual problem. I think you either need this FSM, a scan tool, & some professional (mechanical! ) help, or, preferably, both.

Wish I could be more help, but it looks like you could spend a lot of time tossing effort & parts at the problem & still not fix it. Of course, as soon as I post this, you'll post that you found the problem, no thanks to us!

-- Forgot to ask: Have any mods been done to the lighting system?

No mods to the lighting system. I was told by the dealer that its either the relay or the PCM. I think the PCM stands for Power Control Module, which is what energized the relay. I was told that dealer relays are twice the price but worth it because I've gotten 3 from parts stores and they've all failed within a week. Dealer says they've had this issue with Cadillac's and SUV's from GM and the solution was to put in a relay from GM. Don't know if that's true but I'm tryin it.

 

[RC135_Tx]

No mods to the lighting system. I was told by the dealer that its either the relay or the PCM. I think the PCM stands for Power Control Module, which is what energized the relay. I was told that dealer relays are twice the price but worth it because I've gotten 3 from parts stores and they've all failed within a week. Dealer says they've had this issue with Cadillac's and SUV's from GM and the solution was to put in a relay from GM. Don't know if that's true but I'm tryin it.

Maybe BCM (Body Control Module)? I'd give the relay a try too. Good luck!!

 

[PeterG]

When you install a new relay, the lights work for a while. During the installation, the circuit was open and reset.

After a time, the lights turn off and will not turn on.

Could the sensor is not be sending the signal to turn on the lights. Could the sensor be blind or not tightly connect?

 

[vetteguy05]

I don't think its the sensor. The high beams come on in the dark when the car is unlocked with the fob

 

[c4c5specialist]

HI there,

Once again, it comes down to data and being able to SEE what the BCM is seeing.

That will be critical to the CORRECT REPAIR the FIRST TIME>

Allthebest, c4c5

 

[vetteguy05]

Bcm

HI there,

Once again, it comes down to data and being able to SEE what the BCM is seeing.

That will be critical to the CORRECT REPAIR the FIRST TIME>

Allthebest, c4c5

Well, I took the car back to the dealership where I bought it and they said the salesman had reported the lights not working before I bought it so they're gonna cover the repair. The electrical mechanic said it was either the relay or the BCM itself. The lights worked today upon startup as it was dark and about to rain. I drove about 5 miles and they turned off and the dash lights brightened like the sensor turned the lights off. I turned the switch to the ON position and they wouldn't come on. Because they are turning on sometimes and then turning off, I would be leaning more toward a bad BCM, unless the relay takes a week to reset itself and then can fail more than once.