Georgia Fiero Club Forum

All Things Fiero => Tech Tips, Tech Questions => Topic started by: Donster on April 24, 2021, 07:41:23 am

Title: Need To Know: Headlight Electrical Issue
Post by: Donster on April 24, 2021, 07:41:23 am

Hi all,
Issue has me stumped. Headlights on our 88 were re-wired by previous owner, so the lights would come up, even if only the right side of the light-switch (Running Light) is pushed. In other words, it is not possible to turn on ONLY the running lights, the main headlights come on, no matter if I push the left or right side of the switch.So where might I find the modification/re-wiring the PO did? I hope it's not directly at the control-module, as I know that thing is inside the left front inner fender and a hassle to get to.
So, anyone have an idea?
Much obliged,
\D

Title: Re: Need To Know: Headlight Electrical Issue
Post by: GTRS Fiero on April 24, 2021, 07:50:49 am

Check at the switch.  Likely some pins were changed.

Title: Re: Need To Know: Headlight Electrical Issue
Post by: Fierofool on April 24, 2021, 08:24:28 am

Well, I posted a lengthy reply but I see it's gone, now.  So, here goes again.

There should be some extraneous wires somewhere along the circuit, probably from the bulkhead forward to the headlights.  But the first place I would look, agreeing with GTRS, is at the back of the switch to see if there are any jumper wires in the back of the harness plug. 

As for the headlight module, when I converted my 86 to the Generation 2 system, I jacked up the car and put it on stands.  Then from underneath, I believe I reached up from below to plug in the module.  It's possible that I removed the wheel and fender well liner during the module install, but I don't remember having done that. 

Title: Re: Need To Know: Headlight Electrical Issue
Post by: GTRS Fiero on April 24, 2021, 08:33:45 am

Since you were converting, it may be different, but I had to remove the liner.  Maybe my arms are short.

Title: Re: Need To Know: Headlight Electrical Issue
Post by: Donster on April 24, 2021, 10:35:20 am

No changes visible @ switch.  :(
\D

Title: Re: Need To Know: Headlight Electrical Issue
Post by: GTRS Fiero on April 24, 2021, 11:15:46 am

Are you sure?  Here is a picture of the correct wiring.



As Fierofool posted, if not here, you'll have to follow the wiring to the headlight module.

Title: Re: Need To Know: Headlight Electrical Issue
Post by: Donster on April 24, 2021, 01:52:38 pm

Yes, I am sure.
However, I suspect it might be somewhere in the wires between the headlight switch and the high-beam switch on the steering column.

Title: Re: Need To Know: Headlight Electrical Issue
Post by: GTRS Fiero on April 24, 2021, 01:56:05 pm

Does something different happen, when you turn on the high-beam lights?

Do the low-beam headlights come on, or only up?