Dome light issue

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iamtherealJayy

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Since I doubt my response on other thread will be seen,
Little late here but I’ve got an 87 v20 and the other day I came out and my battery was dead, noticed my some light wouldn’t go out when I opened the switch with my finger(snow on front window tint on side windows can’t see light with door shut) it would get slightly dimmer but if I pressed it a few times it would go out. I ended up getting it to go out after several presses on both sides. Come back later and the lights are back on. My dimmer switch by steering wheel is not in “dome light on” I took both door jamb switches out but could only get the passenger side unplugged. Did not help any so plugged back in. I have read about passenger side only has one wire and mine only has one wire, the driver side had two, my key in ignition buzzer never worked but I never noticed until reading it worked off the same switch. Also remembered that there’s no buzzer for seatbelts either, could these be connected? My horn worked last time I checked. My battery at this point is so drained the charger is reading it as sulfated after it reads it below 6v.
 

PrairieDrifter

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Check the wiring harness running up to the dome, you may have a short to power. My dome randomly stopped working correctly, but everything else worked correctly and ended up being a rotten wire, that I didn't see until I really pulled the harness out.

You may want to check your door jamb switches.
 

iamtherealJayy

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I have new door jamb switches and headlight dimmer switch on the way, I figure can’t hurt to replace them, and the dimmer switch was finicky anyways you had to get it in the right spot for dash lights to come on. Does the wire have to be between the switch in the door jamb and where it goes or could it be grounding out between the dome light and the switch? My truck didn’t have any carpet/floormat so could the wires running under the door sill be worn? Or would that just short and the light no come on at all?
 

Grit dog

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Completing the circuit to ground via the headlight switch or door switches is what turns the light(s) on. They are always + hot and grounding turns them on. So yes if there’s a bare wire that is partially grounding when or where it shouldn’t be will turn the lights on.
Semi unrelated but the wrong bulb in the cargo light will cause a ground path As well. That’s what I found with mine after spending a lot of time diagnosing and then found someone used the wrong bulb in the cargo light.
 

Grit dog

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Find the wiring diagram for those circuits. That will help you understand. Posted on here multiple times. Hope this helps
 

iamtherealJayy

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I have the door jamb switches on the way to replace them, can’t hurt anything, and I’ll check the wires and see if something is grounding possibly. Also the bulb is probably original… the truck has 94k miles hasn’t rolled over yet. If a ground anywhere could cause it I figure it could be under the door sill plate since there was no floor mat/ carpet for several years in the truck so rocks and dirt and stuff could’ve got in there and basically sanded the wires bare.
 

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