Rear doors do not activate dome light - Anybody else?

CruiserTrash

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Out of all the issues my truck has had, this one drives me up a wall almost more than any of them. The rear doors will not activate the dome light. I've cleaned up the dome light contacts and they are good - they work every time with the front doors. I've pulled the switches in the door jambs of both rear doors and they both test good.

I had some electrical "issues" in the rear of the truck from a tow package install, but I chopped out the weird aftermarket epoxy-encased relay box and reconnected all the wires per the FSM. I also cleaned all the connector contacts in the rear driver's quarter area (1983 60 - all the rear electrical stuff is located behind the driver's rear quarter).

Here's a very odd piece of data: At SAS last summer, I was bored in camp one night and ripped out a resettable fuse in my engine bay that was screwed into an arbitrary location on the passenger fender well. The wiring ran from battery + to the fuse, then down along the passenger frame rail to the back where it dead-ended at the trailer connector. More tow package crap. Well, as soon as I ripped that out, the rear doors activated the dome light just enough to make it flicker once or twice when opening. The light didn't stay on, but there was SOME action. That stopped happening after about 10 minutes and hasn't ever happened again.

I've chased wires and it seems like the passenger side door wiring runs through a frame crossmember to the driver's side. I lose it there. This doesn't seem stock to me, but I could be wrong. Has this happened to anybody else? Does anyone have a familiarity with this circuit and where the wires are located?

* * *

Totally separate issue: The tailgate does not activate the cargo light. My cargo light is only a two-position switch (On-Off) and every other one I've seen is a 3-position (On-Off-Door). Did the early 60s - mine's an 83 - come with a manually operated cargo light? Maybe the two position switch is (Off-Door), but that seems odd to me.
 

CruiserTrash

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One more thought: Everything else in the truck is switched ground. Because the dome light works with the front doors (or when turning it to the On position), that means it has a stable 12V supply. So what I'm chasing are the wires from each rear door, which are ground. Do we know where those join the front door ground wires? At the dome light or lower down in the main harness somewhere?
 
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Rear pass door switch wire I believe actually runs through the rear drivers quarter, across the rear of the truck behind the hitch to the pass quarter and then to the switch. So it would be in with that section of harness that was cut up for the trailer wiring. Red/white wire is what youre looking for.
 
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One more thought: Everything else in the truck is switched ground. Because the dome light works with the front doors (or when turning it to the On position), that means it has a stable 12V supply. So what I'm chasing are the wires from each rear door, which are ground. Do we know where those join the front door ground wires? At the dome light or lower down in the main harness somewhere?
They join in the harness and run back to the fuse block. Dome light +12 goes directly to the fuse block
 

CruiserTrash

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Rear pass door switch wire I believe actually runs through the rear drivers quarter, across the rear of the truck behind the hitch to the pass quarter and then to the switch. So it would be in with that section of harness that was cut up for the trailer wiring. Red/white wire is what youre looking for.
You're talking about JUST the passenger rear door switch/ground wire? Mine definitely runs through a frame crossmember so that immediately seems suspect. Because neither rear door operates the dome, however, I'm thinking the fault is AFTER the rear passenger door wire joins the rear driver's side wire.

Like I said in my 83 the entire rear harness is on the driver's side. I think in later vehicles there was a harness on the P-side but for me all wires collect on the driver's side.
 

CruiserTrash

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They join in the harness and run back to the fuse block. Dome light +12 goes directly to the fuse block
The ground/switch wires go to the fuse block you're saying? And then they're grounded at a lug there? The dome light is likely grounded directly to chassis underneath it, so that would have continuity to the fuse box ground behind the kick panel methinks.
 
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You're talking about JUST the passenger rear door switch/ground wire? Mine definitely runs through a frame crossmember so that immediately seems suspect. Because neither rear door operates the dome, however, I'm thinking the fault is AFTER the rear passenger door wire joins the rear driver's side wire.

Like I said in my 83 the entire rear harness is on the driver's side. I think in later vehicles there was a harness on the P-side but for me all wires collect on the driver's side.

There are wires on your pass side too, it comes from the rear tail light harness typically, yes the whole harness is on the drivers side but it crosses over alllllll the way in the back for the pass side tail light

The ground/switch wires go to the fuse block you're saying? And then they're grounded at a lug there? The dome light is likely grounded directly to chassis underneath it, so that would have continuity to the fuse box ground behind the kick panel methinks.

Yes, so the dome light has its own small plug at the kick panel. that then goes to the fuse, the fuse I believe also powers the cig lighter (dont quote me on that)
 

CruiserTrash

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There are wires on your pass side too, it comes from the rear tail light harness typically, yes the whole harness is on the drivers side but it crosses over alllllll the way in the back for the pass side tail light



Yes, so the dome light has its own small plug at the kick panel. that then goes to the fuse, the fuse I believe also powers the cig lighter (dont quote me on that)
So that mini-harness for the passenger side stuff .... where does that come back to the driver's side? Up and over in the headliner? under the body work:above the gas tank? Under the rear seat? I can't find that stuff. Like I said it seems like the p-side door switch wiring drops down and goes through a frame cross member, at least I've chased one wire that does that. and it seems like that wire.
 
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So that mini-harness for the passenger side stuff .... where does that come back to the driver's side? Up and over in the headliner? under the body work:above the gas tank? Under the rear seat? I can't find that stuff. Like I said it seems like the p-side door switch wiring drops down and goes through a frame cross member, at least I've chased one wire that does that. and it seems like that wire.

It goes under the body all the way in the back, behind the gas tank. If you lay under there youll see it. In my 82 the only wire that runs out of the quarter like you say is for the fuel level sender
 

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Out of all the issues my truck has had, this one drives me up a wall almost more than any of them. The rear doors will not activate the dome light. I've cleaned up the dome light contacts and they are good - they work every time with the front doors. I've pulled the switches in the door jambs of both rear doors and they both test good.

I had some electrical "issues" in the rear of the truck from a tow package install, but I chopped out the weird aftermarket epoxy-encased relay box and reconnected all the wires per the FSM. I also cleaned all the connector contacts in the rear driver's quarter area (1983 60 - all the rear electrical stuff is located behind the driver's rear quarter).

Here's a very odd piece of data: At SAS last summer, I was bored in camp one night and ripped out a resettable fuse in my engine bay that was screwed into an arbitrary location on the passenger fender well. The wiring ran from battery + to the fuse, then down along the passenger frame rail to the back where it dead-ended at the trailer connector. More tow package crap. Well, as soon as I ripped that out, the rear doors activated the dome light just enough to make it flicker once or twice when opening. The light didn't stay on, but there was SOME action. That stopped happening after about 10 minutes and hasn't ever happened again.

I've chased wires and it seems like the passenger side door wiring runs through a frame crossmember to the driver's side. I lose it there. This doesn't seem stock to me, but I could be wrong. Has this happened to anybody else? Does anyone have a familiarity with this circuit and where the wires are located?

* * *

Totally separate issue: The tailgate does not activate the cargo light. My cargo light is only a two-position switch (On-Off) and every other one I've seen is a 3-position (On-Off-Door). Did the early 60s - mine's an 83 - come with a manually operated cargo light? Maybe the two position switch is (Off-Door), but that seems odd to me.
The rear cargo light should turn on when you open the hatch. There are 3 modes. On-Off-Door
 

CruiserTrash

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The rear cargo light should turn on when you open the hatch. There are 3 modes. On-Off-Door
I took the cargo light apart and it looks identical to OEM but only has two contacts.... On and Off I guess.

FWIW I have read stuff on Mud about the switch being inside the lock mechanism and how to clean it out.
 
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My rear side door switches sometimes fail to light the dome light because the protective rubber booties over the switch are old and stiff on cold days (like the truck's owner), and keep the switch 'trapped', thinking that the door is shut.

If I tug on the bootie when the door is open, the light comes on. Likely not your exact problem, but it could be compounding the troubleshooting.
 

CruiserTrash

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My rear side door switches sometimes fail to light the dome light because the protective rubber booties over the switch are old and stiff on cold days (like the truck's owner), and keep the switch 'trapped', thinking that the door is shut.

If I tug on the bootie when the door is open, the light comes on. Likely not your exact problem, but it could be compounding the troubleshooting.
Funny you mention this .... for the first time EVER my driver's door did this last night. I knew exactly where to look so thanks for that!
 

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