4WD indicator light stuck on

[CodyLHen]

Hello everyone. I have been helping a friend restore a 1969 fj40. We have had our fair share of difficulty. Most of the work I have helped with is electrical issues. There were a lot of electrical gremlins when he bought the truck from the PO. Slowly but surely we have managed to get most of the problems worked out.

The next problem on the list is that the 4wd light seems to be stuck on. I believe that it is just the light because I was told that he engaged disengaged the 4wd and it seemed to work fine. My question is, where is the switch to activate the 4wd light on this vehicle? I don't see any wires coming out of the switch it self, nor do I see anything that comes from the vacuum switch on the firewall. I have been searching the site and I have found some stuff on a vacuum solanoid as a common problem, but it does not appear that this model has a solanoid. Should it have one or is it an earlier model that does not have this feature? I was crawling around under the truck trying to find a electrical connection coming from the transfer case and found a wire that is not connected to anything coming out of the wiring harness near the t case.

I'm gonna go work on it with him tommorow and I plan on trying to spin the front drive shaft. I have read that this will indicate wheather or not the 4wd is truly disengaged.

Thanks for any help.

 

[Living in the Past]

The switch is on the nose cone of the transfer case just behind vacuum diaphragm on passenger's side. you will see the two wires. Chances are the vacuum shifter isn't working.

 

[CodyLHen]

Is the vacuum shifter your talking about a switch specifically for the light or are you referring to the the shifter that enables the 4wd. Thanks for the fast response. It gives me a spot to start searching for wires. The PO was kind of a bone head. He did a full re spray and did not do a good job refitting the the wiring harness so it will be good to pin point the switch so we can trouble shoot from there.

 

[Living in the Past]

Is the vacuum shifter your talking about a switch specifically for the light or are you referring to the the shifter that enables the 4wd. Thanks for the fast response. It gives me a spot to start searching for wires. The PO was kind of a bone head. He did a full re spray and did not do a good job refitting the the wiring harness so it will be good to pin point the switch so we can trouble shoot from there.

The switch that lights up on the dash is a spring loaded switch that is screwed into the front partof the transfer case right behind the diaphragm that has the two vacuum hoses hooked up to it. It on the transfer case just inside frame on the passenger's side. It works automatically when the transfer case is in 4WD.

 

[Teebag]

check for low oil

 

[Coolerman]

Here is a pic of the switch location. The circuit works as follows: +12V comes into one side of the light via a GY wire. Another GY comes from the other side of the light and goes to one side of the t-case switch. A WB wire comes from the other side of the t-case switch and continues on to the main chassis ground on the frame. So when the t-case is engaged for 4WD the switch grounds the light causing it to light.