Courtesy light/door switch question

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Vetal4

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Ian
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1988
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V30 Crew Cab
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350
I recently pulled out the door switch to free it up and get courtesy lights working. I know there is supposed to be two wires running to the door switch, one is the tan wire to the convenience center, the other is the white wire to provide a ground to the courtesy light. I only found the tan wire hooked to the switch....no white wire. I fished around in the panel with a piece of wire, nothing. Got under the dash, only the tan wire runs through the silicon plug into the panel, no evidence of a white wire there.... so my question is: is it possible that the door switch hooked to the courtesy light was an option? Is it possible that the truck's courtesy light is only activated by the headlight switch from the factory? I should add that, even though tan wire is plugged into the door switch, there is no buzzer in the courtesy center and doesn't look like there ever was one plugged in.
 

Jgonick

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Not sure if this will help, but this is the 1988 R/V wiring. I am assuming there is a typo NAT is probably TAN -I've never heard of a color named NAT.
Edited- NAT is actually means “natural”


1988 wiring manual LINK

page 310
just an FYI - 1988 R/V starts around page 243 (section D)
 

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Last edited:

Vetal4

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Location
New Mexico
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Ian
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1988
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V30 Crew Cab
Engine Size
350
Not sure if this will help, but this is the 1988 R/V wiring. I am assuming there is a typo NAT is probably TAN -I've never heard of a color named NAT.
Edited- NAT is actually means “natural”


1988 wiring manual LINK

page 310
just an FYI - 1988 R/V starts around page 243 (section D)
thanks, that is helpful actually. That wire wire just isn't there though. Weird.
 

Jgonick

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Actually- I looked at the 85 wiring diagram (for my truck) and it is a dotted line that means it is present in some vehicles but not all vehicles. So you are probably correct that it was an option.
 

Vetal4

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1988
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V30 Crew Cab
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350
Actually- I looked at the 85 wiring diagram (for my truck) and it is a dotted line that means it is present in some vehicles but not all vehicles. So you are probably correct that it was an option.
I'll copy/past my PM reply here so its visible/maybe someone can provide more info:


Hey, just replied to your post. Yeah that white wire just isn't there, and I see no evidence of there ever being one. I wondered because someone installed an aftermarket dome light, so i wondered if they messed with it.....but they were so hamfisted about it I would think I could probably tell if they'd been in there. There was nothing but the NAT wire connected to the switch and it really looked like no one had ever been in there, I would also think that the that rubber/silicon plug where the wires passes through the kick panel would look like it held another wire, but i doesn't.....

It would make sense that its an option, this truck is a pretty low optioned one as far as creature comforts are concerned (government order).....just weird they would even bother with the NAT wire to the buzzer (which also looks like its absent from the factory)
 

legozombie

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Do you have a picture of the switch itself? A picture may offer some insight. I posted about rebuilding them here and they were just one wire that was powered by a single wire and completed ground with the cab where they screw on bare metal. If there isn't one, I'll bet you can can just tap into the single wire there if the signal needs to go anywhere else.
 

KamperBob

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Not sure if this will help, but this is the 1988 R/V wiring. I am assuming there is a typo NAT is probably TAN -I've never heard of a color named NAT.
Edited- NAT is actually means “natural”


1988 wiring manual LINK

page 310
just an FYI - 1988 R/V starts around page 243 (section D)

Thanks so much! I'm rebuilding an 84 k30 and dome lights were an issue. The diagrams will help finish the work. One thing I did was convert to LED bulbs. The footlight works okay as is. The ceiling lamp is super bright now. Too bright for everyday use but when I want to read something (map, etc) especially with aging eyes that brightness comes in handy! SO what I did was add a dimmer knob near the driver side shoulder strap which intercepts that wire. The knob rotates, snapping completely off full left, and increases brightness to the right. Very intuitive. Usually I either leave it off (not advertise myself) or leave it on the lowest setting which is enough and comparable to the OEM bulb. I hadn't yet tracked down the upstream signal to intercept and dim and footlight as well. I expect the wiring diagrams will save time finishing that mod. Thanks again!!
 

Vetal4

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Location
New Mexico
First Name
Ian
Truck Year
1988
Truck Model
V30 Crew Cab
Engine Size
350
Do you have a picture of the switch itself? A picture may offer some insight. I posted about rebuilding them here and they were just one wire that was powered by a single wire and completed ground with the cab where they screw on bare metal. If there isn't one, I'll bet you can can just tap into the single wire there if the signal needs to go anywhere else.

I reinstalled it but it was similar to the one in your post, didn't have a barrel connector, but instead had two blades... I checked out the vehicle information kits for 1986 through 1988, 1988 was all OBS, no squarebody info (though I think my SPID has some cross pollination between the two, that might make a good post in itself). However all mention of the door switch activation of the courtesy lamp (or any lamp) is in context of the dome light option. I think, therefore, its safe to conclude that the door switch activated the courtesy lamp only if you has the dome light.
 

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