Headlight issues on 96 Tahoe

[MASTERBrian]

Trying to help my nephew figure out what's going on with the lights on his recently acquired 96 2 door Tahoe with 5.7l vortec.

The previous owner told him only the high beams were working, but dim enough to run full time. I think he also mentioned something about fixing something in the column, which I'd think would be the turn signal switch with the high beam switch and cruise, etc. I didn't catch the entire conversation.

Needless to say he'd like to get things working properly. Last week he swing by and we liked over some things and it seemed to me like all was good, but then he called a few days later saying they stopped. Apparently the DTR, daytime running lights, fuse is blowing. He has put a couple in and everything works for an hour or so then blows the fuse again. He came by earlier and the battery terminal connection was loss due to bad battery bolt. Replaced that and for the cables tightened nicely. Popped in New 20amp fuse and everything works for a good while so he left. Hopeful it was just a poor battery connection.

An hour or so later and all out again, except for high beams, driving and tail lights. I went over and pulled the bezel off the dash. It appears the headlight switch has been tampered with as a few tabs broken and the back cover of it seemed loose. I also noticed if I flick the high beams on, the switch makes a buzzing noise and then a delayed click and the highs come on. If I turn the high beams off, again a delay and then more noise and the back side of switch appears overly warm. I tried to disassemble the switch to look inside, but it was gettig dark and I didn't have great light and tools handy, but seems very simple inside.

I went ahead and ordered a replacement on Amazon, which should be here Saturday, but I'm curious if this seems like a logical cause of the issue OR if the cause is somewhere else and messing with the switch? For $35 it was an easy part to throw at it, especially since it appears compromised in past. I also question the turn signal switch, but considering the high beams work, I'm thinking not here. That part is around $70-300 because of cruise. Might hunt one at salvage yard and also check harness out there.

I earlier was watching a YouTube about a DTR issue, and apparently there's a module for that but they seemed to be discussing different issues. I'll also mention the headlight lens has moisture, so I ordered new lenses as well. He just purchased new bulbs. Not sure if the moisture would cause this, but I had moisture in my 03 burb DTR lights lens and those tend to have burnt sockets causing bulb burnouts I replaced my lens and socket asking with led bulbs and no more issues for me. So, is it possible the moisture in his could cause a short?

Any ideas here? I'm thinking the clicking/buzzing sound is a giveaway here, but alas that DTR fuse is currently blown, so maybe that is cause of click. Hmmmm.....

I've also considered having him upgrade the bulbs to up the brightness because these do seem awfully dim. What's a good alternative for that......led...halogen....?

[scotto0609]

Is there heat at the headlight switch? Don't hesitate to change the switch ASAP. I had a similar problem with my 92 yukon and overnight the switch shorted and melted the whole corner of dash. Had to replace whole interior! If it were me I would disconnect battery until rectified. Good luck

[MASTERBrian]

Ouch, thanks for the warning. I have him coming over after work to check it out. Surely just not driving at night and unplugging the switch or pulling fuses should take care of any issue. I want to see if the switch is HOT with the lights not being on....

[diveplane]

Originally Posted by scotto0609

Is there heat at the headlight switch? Don't hesitate to change the switch ASAP. I had a similar problem with my 92 yukon and overnight the switch shorted and melted the whole corner of dash. Had to replace whole interior! If it were me I would disconnect battery until rectified. Good luck

wow thought the fuse would have prevented the short wtf?

[scotto0609]

Would have thought so too but something didn't function correctly. On the plus side I only had to change out about 8 wires total.

[90OBS]

I had trouble with my 97 headlights. I think the switch fails due to a factory wiring problem . I think LMC has the solution with a wiring harness.

http://www.lmctruck.com/icatalog/cd/full.aspx?Page=68

[MASTERBrian]

Got the new switch installed the other night, problem came back within the hour. It makes a strange sound when headlights low beam turned on. With brights on, no sound.

The harness from lmc sounds interesting. Would that be a difficult swap? Considering trying to hit a salvage yard to grab a used harness and/or turn signal switch and to get a look at how it all goes together. Maybe I try this harness instead.

[MASTERBrian]

Scratch the lmc idea, this truck has day time running lights.

[90OBS]

Yep, scratch that.

[MASTERBrian]

Went out and looked a bit more and it was the under dash relay that's blinking and buzzing when headlights turned on. Noise goes away when I turn on brights. Wondering if relay bad. I might borrow from my 99 just to see.


*****NOT the relay. Worked for thirty seconds, then started the beeping, buzzing, clicking sounds and no dims. FWI, fuse is still burned out on DRL. This must be a harness, DRL module, turn signal switch or something else I'm unaware of.

New lenses will hopefully bee here tomorrow.

[MASTERBrian]

I'll also mention the large harness that goes through right by the parking brake has a small 5-6? Wire harness coming out and that small harness was rubbing on the parking brake release cable. Then there's another harness that comes off the under dash relay panel and goes to rear that was folded over. I didn't, upon quick inspection, find and brakes or bare wire though.