Headlight problems

[firethorn]

I have a 1998 Seirra 1/2 ton with the four headlights. The daytime running lights come on when the parking brake has been release. The daytime running lights stay on when I turn on the parking lights but when I turn on the headlights the headlights completely turn off. I have replaced the headlight switch and the daytime running lights relay and they still turn off when I turn the switch to headlights. Any help?

[GM-Tech]

That's a little confusing. Is it the headlights that don't work or the DRL's?

[firethorn]

I have a 1998 Seirra 1/2 ton with the four headlights. The daytime running lights come on when the parking brake has been release. The daytime running lights  stay on when I turn on the parking lights but when I turn on the headlights the headlights completely turn off. I have replaced the headlight switch and the daytime running lights relay and they still turn off when I turn the switch to headlights.  Any help?

 

<{POST_SNAPBACK}>

 

 

DRL do work, it is when I turn the Headlights on that the lights go out. Neither the low beams nor high beams works.

[GM-Tech]

Could be the daytime running light module (not relay). This is taped to the harness under the left side of the dash. Besides DRL's, this operates the headlights.

[firethorn]

OK, I have now replaced the Daytime running lamps module and I still have the same problem. DRL works but when I turn the headlights they (the headlights) don't work. Any other ideas????

[pwall]

I had a similiar issue in my 2002. No headlights at all, but DRL and fog lights were ok.

Turned out to be a 'multi-purpose' switch in the sterring column that went out, which was a $400 part.

[firethorn]

How did you find out it was a "multi-switch" in the steering col????

[pwall]

Had to bring the truck into the dealership.

I was thankful for the after-market warrenty that covered it all.

[firethorn]

I would think that there has to be a way of checking this out. Anyone know how to do it???

[firethorn]

I notice that there was a series of tests that can be done to help find out why your DRL are not working, do they have a step by step to find out why your headlights don't work????????

[GM-Tech]

I notice that there was a series of tests that can be done to help find out why your DRL are not working, do they have a step by step to find out why your headlights don't work????????

 

<{POST_SNAPBACK}>

 

 

 

Sure. Here ya go. The formatting sucks and it's difficult to follow in this form but it's the best I can do given the forum limitations. The diagnosis leaves a lot to be desired if you ask me.

 

After each question where it tells you to go one of two ways, the first way is if the answer was YES and the second if it was NO.

 

The first one, "Did you perform the Headlights System Check?" you can skip. It just tells you to try the various headlights... do they work. Obviously not or you wouldn't be diagnosing a problem with them.

 

 

------------

 

Low and High Beams Headlamps Inoperative (Daytime Running Lamps)

Step

Action

Value(s)

Yes

No

 

1

Did you perform the Headlights System Check?

--

Go to Step 2

Go to Headlight System Check

 

2

Turn the headlamp switch to the ON position.

Backprobe the headlamp and panel dimmer switch connector with a test lamp from cavity G to ground.

Does the test lamp light?

--

Go to Step 3

Go to Step 4

 

3

Disconnect the headlamp dimmer switch connector.

Connect a J 35616-200 from the headlamp dimmer switch connector, cavity D, to ground.

Does the test lamp light?

--

Go to Step 5

Go to Step 6

 

4

Replace the headlamp and panel dimmer switch.

 

Is the repair complete?

--

Go to Headlight System Check

--

 

5

Replace the headlamp dimmer switch.

 

Is the repair complete?

--

Go to Headlight System Check

--

 

6

Repair the open in CKT 10 (YEL) between the headlamp and panel dimmer switch.

 

Is the repair complete?

--

Go to Headlight System Check

--

[firethorn]

I'll give it a try tomorrow. Thanks.

[GM-Tech]

Here's a graphical version... By the way, the J-35616-200 tool mentioned is just a regular ol' test light.

 

[barron]

Here's a graphical version... By the way, the J-35616-200 tool mentioned is just a regular ol' test light.

 

 

I had the same issue with my 97 GMC. Using ideas in this forum, I found two wires loose/burned at the connector of the multi-function switch on the steering column. They had apparently worked loose from the movement of the tilt wheel. The headlights would flash on and off when you were adjusting the steering wheel position.

Now I just have to decide if I am going to fix it myself or take it to the shop. I really don't want to deal with the airbag.

Thanks for this forum.

 

Barron