97 Sierra headlight issue

[redagain]

I recently picked up a very nice rust free Sierra, which is damn rare here in Wis, got a headlight issue Im trying to sort. My last GMT400 was a 94 1500 W/T that i bought new so its been a while...been looking for a good specimen. When the headlight s are on auto setting the brights wont work..with the switch turned to full on..only brights work..you flip the stalk for dims and no headlights. Thx much

You must be registered for see images attach

 

[df2x4]

I have to ask... Do you have a picture of your headlight switch? To my knowledge none of these trucks ever came with an "Auto" setting on the switch. I've never seen one.

 

[east302]

Agreed with the above, it’s all manual operation. You have the first setting past “off” which is the parking lights only. High beams will not come on.

The second setting turns the headlights on. If the low beams do not come on at this setting, then either the bulbs are out or you have another issue. I’d suspect a bad multifunction lever (the whole assembly) as the wiring can get damaged by hard use of the tilt steering, leaving you with no low beam headlights. But confirm that this is what you’re seeing, I’ll try to dig up the wiring diagrams so you can locate the problem.

You must be registered for see images attach

Sent from my iPhone using Tapatalk

 

[redagain]

sorry..believe you are correct...i just bought this yest...was going by what the po said...that being said....i have dims with the daytime running lights...but when i go to on..only brights...multi function switch in column?

 

[east302]

Looking at the wiring diagram, the headlights are fed from the fuse, through the dash headlight switch (“Headlamp and Panel dimmer switch”), through the DRL
Module, through the multifunction switch and then through the DRL relay on to the headlights. The “Headlamp dimmer switch” is a part of the multifunction lever/switch/thing.

Since your high beams work, I’d say that everything ‘upstream’ of the multifunction dimmer switch is good.

Here is the GM diagnostic for it. If the previous owner let the tilt steering slam up a lot, it could have damaged the multifunction switch wiring. My Tahoe did the same thing; if I was going to throw a part at it, it would be the multifunction switch. But, it wouldn’t hurt to run through these checks with a multimeter. If it’s just a damaged wire, you may be able to repair it and save the expense.

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

Sent from my iPhone using Tapatalk

 

[redagain]

Thanks for the info..much appreciated...I did a multifunction in my 93 yukon gt...what a PITA...95-98 any easier?

 

[east302]

No, it’s not difficult. Check YouTube, here’s one video but there may be others.

xc_hide_links_from_guests_guests_error_hide_media

Sent from my iPhone using Tapatalk

 

[JackE]

Yes, much easier. You don't have to feed the wires down through the tube. The hardest part is getting the column cover off without breaking the mounting points. That part is a pain in the crack!

 

[Chuck_13]

Man,that's what I love about this site.Extremely useful replies,with pictures!You guys are AWESOME!

Thanks,east302!