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Need help with electrical issue

Since this issue started, have you pulled the door switches back out to inspect? It's the most likely place for a short to occur, but I don't see it mentioned.

Beyond that, you may have to just follow the wiring around, possibly cutting splices to divide and conquer. I do think it travels under the DS sill plate on the way to the dome light and the hard top light.
 
Please note there are 2 power connections the fuse, and circuit 140.8 on diagram. If both are not disconnected circuit will remain hot.
 
I cant recall, is there a switch on the tailgate that turns the lights on when it is opened? There was one on the barn doors of my last Suburban that would stick and leave the interior lights turned on.
 
Blue85 said:
Since this issue started, have you pulled the door switches back out to inspect? It's the most likely place for a short to occur, but I don't see it mentioned.

Beyond that, you may have to just follow the wiring around, possibly cutting splices to divide and conquer. I do think it travels under the DS sill plate on the way to the dome light and the hard top light.
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Yes, I have pulled the door switches out AND disconnected the headlight switch and the dome lights and courtesy light still remain on which means it is a short to chassis on the white wire.
 
No, K5 doesn't have a tailgate switch. The note on the schematic says "Suburban only" for "Door end gate harness extension".
 
Wes Harden said:
Please note there are 2 power connections the fuse, and circuit 140.8 on diagram. If both are not disconnected circuit will remain hot.
Click to expand...

Yes, I can see that. The issue is a short to chassis of the white wire. Do you know if circuit 140.8 is a fuseable link?
 
I know on my '83 when the T/L CTSY fuse is out then the dash lights and tail lights obviously don't work but it also causes the light under the dash to stay on any time the headlights are on and possibly an issue with the dome light operation too. I just ran into that after getting mine going from sitting a long time and I have no idea what happened to the fuse but it was gone. Plugged one in and everything went back to normal.
 
I think that looks like it comes off the alternator or battery according to the schematic. My guess is that it comes from the junction block on the firewall above the rear of the engine. Should be easy to pull it there and check.
 
There isn't a switch on the tailgate for dome lights on the K5s.

I know that that I had to pull 2 fuses to kill both the dome light and the courtesy light. On mine it also killed the constant hot for the radio memory.
I have also seen a 2 wire plug just 6" from the fuse block which allowed GM to plug in whatever dome light harness that was needed, or none at all. It allowed them to use the same fuse block for more models which is why the All-data schematic showed rear switches, (for a suburban).
The numbers on that schematic should be RPO codes, not model years.
But anyway, I still believe that there should be a plug to disconnect the harness down by the fuse block.
 
Yes I explained how you could use an ohm meter to locate the short, after the power is removed from the circuit. Then we got side tracked about removing power from the circuit.
 
4X4HIGH said:
Yes, I can see that. The issue is a short to chassis of the white wire. Do you know if circuit 140.8 is a fuseable link?
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Scott, maybe with the shorted power up something else electronic got hurt and there’s a circuit created to ground. What do you have for aftermarket electronics, ignition system, sound system, ECM? Might be worth unplugging each individually then power up and check to see if the problem goes away, as you know pulling all the fuses individually only interrupted the hot side of each system, not the grounded.

Before you go through that painful test, do all the different electrical systems operate properly? Clock and presets aren’t lost every time the key is turned off, nothing else weird happening?
 
Yeahi understand about the fuse only removing the hot side, unfortunately EVERYTHING else in the truck is working correctly and yes the radio presets and clock remain set Unless I remove a battery cable.
 
When you say you checked the door switches, does that mean you pulled them out?

Just wondering if since you replaced them, one of the connectors popped loose and is grounding inside the body? Or, the wiring was already damaged and when the wire twists up as you screw the switch in, the damaged portion contacted the body after bouncing around on the road for a bit.

Looks to me like if a wire was pinched in the engine bay, it would have to be a battery + (all grounds for interior lighting are inside the cab), and all the related terminals I see on the fuse panel, according to the posted diagram, are ganged, so other circuits would also have a problem.
 
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I removed the door switches from the A-piller AND removed the wiring from the switches and the lights still remain on. I also had the headlight switch removed from the wiring and set it on my seat and the lights were still on.
 
I'm being lazy, but IIRC there is an auxiliary plug that also powers that circuit. Unplug that and it should kill the power.
 
dyeager535 said:
I'm being lazy, but IIRC there is an auxiliary plug that also powers that circuit. Unplug that and it should kill the power.
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There is a fuse for T/L Courtesy which I have already removed and the dome lights STILL remain on but I cant remember with 100% certainty if the courtesy light turns off.
 
Look at the wiring schematic then check your panel. Circuit 140 is not coming from a fuse position, its coming off one of the auxiliary spots on the panel.
 
dyeager535 said:
Look at the wiring schematic then check your panel. Circuit 140 is not coming from a fuse position, its coming off one of the auxiliary spots on the panel.
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I dont know where you see a circuit 140 but circuit 40 comes from behind the fuse panel and I believe is the fuseable link wire off the starter. At any rate that wire is not a plug in auxiliary on the fuse block.
 
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