Key off drain courtesy light...

I have a 1990 k2500 with a key off drain and when I pull the courtesy light the test light goes out...I pull out the bulbs in the cab and this did not help..Could this have something to do with the 4X4 light not coming on when the front locks in???Any thoughts on what to test next???



This may or not be related but when I key on I hear the sound of something ticking in a fan but it comes for the center of the dash no ware near the heater fan..

Thanks!!!

I had simular problem, mine turned out to be a ground wire. And it was a small one, one that screwed to inner fender-well. Had a little corrosion built up around screw. Took it off, sanded clean an it fixed my problem. Hope this helps, good luck, keep us informed please.

was it the ground right off the neg batt cable???

Or one under the cover on the firewall??? Was thinkig about disconnecting the hood light...

Thanks for the reply!!!!!

Anyone with a diagram of the courtesy light circuit???? Or know where I can find one??

I have lulled the light for the glove box and cigarette lighter today,cleaned all the grounds and replaced the neg batt cable what is next???

Thanks.........

I replaced the buttons that the doors press in to kill the lights still no change.. I took it for a ride and found that the directional lights don't work either,but the hazards do...So I replaced the flasher and still no go..

I got a copy of the wire diagram from AZ and some how it looks like the tan wire from the left door switch runs into the E: on the direction switch..So I'm kinda thinking this may all be one problem..

Anybody with any ideas????

Did you just purchase this truck, or did your problems just start?
The ticking noise you hear when you turn the key on....is it close
to where your 4x4 light is (that does not work).
Please feed us all the info you think is important, it all helps. And just to
make sure, the bulbs you are replacing, blinkers, stop, turn etc. It does matter getting the correct style, numbers, 1137, 1157 ect.

If you had this truck a while, and problem just started, may be a pinched wire, ect.

Please let us know about the trucks history, any recent wrecks or been pulled out of the mud, anything to "jar things up" a little?

Ok I got the truck two weeks ago.I was told the ring and pinion were bad and the radio did not work..

What I have done since swapped rear bumper,trailer hitch,tailgate..Also front bumper,grill and hood..Then decided to swap the rear end from my 1500 to save money and I had to swap front diff's as well..The 2500 had 373's and the 1500 342's...So I swapped the front diff first found a bad hub and axle so I swapped them also.. O and I swapped shocks and rotors too..After I got the front diff in I pulled the floor shifter into 4 high and the light came on..It has not worked again..So then on to the rear end swapped the entire rear end and shocks..Truck goes down the road but with no 4 wheel drive so I got to looking and the vacuum actuator on top the transfer case was bad so I swapped it out..Now it goes into 4 wheel drive but the light on the floor shifter still does no light up..

So I'm getting ready to drive it now I had installed my head unit with adapters no cut and splice and I put in a batt. to find the radio does not power up,turned out to be a missing fuse..In looking for the problem with the radio I found the key off draw...

Now what I have down for the key off draw..Using a test light between the batt. neg cable and batt. post I started pulling fuse's and the light on the test light went out when I pulled the courtesy light fuse...So from there I have pulled all the bulbs in the cab even the cigarette lighter light and glove box bulb..I replaced the door switches as well..I got a copy of the schematic's from AZ and started studying them..I found it odd that the last wire in the loop is a tan wire running out the left door switch and it goes into the terminal E of the direction switch...Not so odd tho when I went for a ride and found the directional switch does not work...I have cleand all the grounds I could find and I also cleaned all the connections under the cover on the firewall under the hood.. I also tried disconnecting the under hood light and the light on the fender next to the batt..I did replace the batt. neg. cable too...

What I want to try today is swapping out the directional switches from the 1500 to the 2500 one problem tho the 2500 has cruse and the 1500 doesn't so not so sure it will plug and play...

Any other thoughts????

I need all the help I can get...

One more update the radio does not work unless the courtesy fuse is installed....

I don't see how they are related but????

Just thought of something I did last week...There was a house wire run from under the hood. From the the positive side of the batt but it was disconnected when I got it and there was some more just wrapped around the brake lines under the master cylinder..I followed the all the way back the the goose neck plug hook up in the bed..I just cut them and pulled them out the truck. Now I wonder if that is why the blinker stopped...

Wow, you have put a little time into this truck, ha! But now it sounds like you are narrowing it down, somewhat.
Seems that the old goose neck hitch and wiring harness was an add-on, the truck itself, should still have factory wiring ran to the back of bed, for all your lights. If you have some lights on, (at back of bed) like brake lights, park, license plate, blinkers etc, they "may" have spliced into the wiring harness. And when you cut them loose an pulled goose neck plug out, you created an
"open circuit". Will have to track down wiring harness that leads to back, for lights.
Its hard enough to track down factory wiring, but when people "add-on" wires splicing different colored wire here an there, thats tough:banghead:
Start where you cut old plug for goose neck, may not be that bad!!!!!!
Please keep me informed, good luck!

And you should have some kind of a ground, added-on for goose neck plug. And you will still have your factory ground at rear of bed frame area for the wiring harness itself.
Happy Hunting!!!!!!!!!! good luck

Does it have trailor brakes installed for goose neck, (small box mounted somewhere under dash, close to steering wheel), if it does there will be some more wires to look for. Mine has three coming off it, white red an blue. Mine has trailor brakes, and of coarse, another add-on!!!!!!

Nope no box under dash that I have found...All the wires look great I have found no other splicing just the goose neck.. I know at some point in time it had a fifth wheel in it.Why it was removed will always be a mystery...

I will go hunting tomorrow I hope it is just a simple ground but my luck is not that good....

It is coming along..All I use it for is going to the dump and gathering firewood..

http://i139.photobucket.com/albums/q301/southbound_bucket/1990%20K2500/DSC03849.jpg

http://i139.photobucket.com/albums/q301/southbound_bucket/1990%20K2500/DSC03854.jpg

O and thanks for your help!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

The ticking noise you hear when you turn the key on....is it close
to where your 4x4 light is (that does not work).


Yes it is close to the 4X4 light that does not work...
So what does this mean??The 1500 transfer case had a sort of whirling sound I got use to....

I did not get to look at the wiring today I spent half the day pulling the tranny and transfer case out of the donor truck..Thought I had it sold but dude never came by..I hate that kinda stuff..


Anyway I will get back under it tomorrow and look at the goose neck switch see what I did wrong...

Dude I'm just throwing you hints, you had said in your first post that the 4x4 light did not work, then you could hear the ticking noise in dash.
That may be a place to check also, ticking noise is never good! Maybe something grounded or arcing there??????????
Does it go into 4x4 drive now?

First yes the 4X4 works just fine...The light just does not come on...

I removed all the wires for the plug for the goose neck and all the blinkers work except the pass tail light and I'm gonna swap the whole thing out tomorrow and go from there...

Still have the key off draw tho...

Even if they are just hints keep them coming I need all the help I can get...

Thanks again...

Swapped out tail light today and still no blinky,,,I will take a look at the wires tomorrow...

Fixed!!!!

I unplugged the after market head unit and it went away..

I will find power elsewhere tomorrow....