Headlight switch

[alpinecrick]

97 K1500 it's an early model year truck and almost identical to the 96 models. Low mileage.

Chasing a small amp draw when the truck is off, about .2-.3 of an amp. When I pulled the 50 amp lighting fuse under the hood the draw went to zero. Plugged it back in and had a .2-.3 draw.

Pulled the courtesy light fuse (#3) in interior fuse panel and reinserted it, amp draw is now .06, which is probably within the clamp meter's margin of error. I also noticed my dome override switch sometimes works, most of the time won't work.

I vaguely recall a few posts where guys found the headlight switch was shorting or causing a ghost draw. My first guess is the headlight switch. This truck did some miles on bigtime washboard county/Forest Service roads a couple weeks ago.

Question is, have any of you ran into the headlight switch being a culprit in a slow drain of the battery?

I have a switch in my RA cart, can't decide whether to pull the trigger on parts cannon......

 

[alpinecrick]

Has anybody had a headlight switch go bad.....?

 

[454cid]

Has anybody had a headlight switch go bad.....?

Mine started to keep the dome light on until I took it apart and cleaned it.

 

[alpinecrick]

454,
I thought about pulling it and cleaning, but my dome overide button only sometimes stays down, suggesting to me that things may be plumb wore out in the switch. Although a good cleaning may do the trick.

 

[454cid]

454,
I thought about pulling it and cleaning, but my dome overide button only sometimes stays down, suggesting to me that things may be plumb wore out in the switch. Although a good cleaning may do the trick.

Actually, that might be hard grease. After cleaning mine, I regreased it with vasoline.... I think. But don't use vasoline, get real dielectric grease. I did it before I knew better. I had grease leaking out of the switch for quite awhile as vasoline melts easily.

I have almost 300K miles on my truck with the original switch.

 

[alpinecrick]

I pulled it into the shop where I usually keep it. That damn 97 is spoiled and it probably thought it had been abandoned when I left it outside for 3 whole days.

Tomorrow I'll pull the switch and clean the *****......

 

[df2x4]

The original switch in my Suburban went bad, but I don't know if it had any parasitic draw or not. It just quit letting my dome lights turn on one day, like the override was on all the time. Replaced it with a new one and no more issues.

 

[alpinecrick]

454, I sure admire you for disassembling that headlight switch! When I got mine out there was something rattling around in there. Got the front and back off, fished the loose piece out, it was a brass/copper cylinder thingie mushroomed on each end. Pushed the dome overide a couple times and it popped out and a retainer fell out too. Could not for the life of me figure how that dome button retainer went back in. In the process of messing with it I realize there is something else rattling around in there too.
Screw it.
I ordered a new one.

Incredibly Amazon had a Standard Motor Products switch for $25 less than RA.
But my trip odometer quit last year, so I dove into the gauge cluster and found the plastic gear had split. Glued the gear back together with Devcon Plastic Welder and I'm pretty sure it's gonna work.
But this afternoon my 96 threw a P1345 code for the third time this year.
One step forward and two steps back today........geeeez.

 

[454cid]

I didnt go back to see what year your truck is, but if you have the early interior I have a different switch, since I have the late interior...I did feel a bit like I was doing surgery though.

 

[alpinecrick]

Both my GMT400's are the later interior. Today I recalled I had to replace the switch in my 91 at some point......