Need help with rear window

[hindsight]

I recently bought an FJ55 that had been sitting outside for 20+ years. We have it running and now it is time to attend to the little things that do not work.

A little history that may be pertinent to the problem.

Before the FJ55 was left to sit, the rear window was broken by vandals. As a temporary measure the PO replaced the window with a sheet of plexiglass.

The rear gate panel was removed and left open during the time of exposure....the inside of the vehicle was very well protected from the elements (except mice). It is my belief that the PO abandoned the vehicle shortly after the window was replaced.

After inspecting the manual...everything appears intact as far as wiring and mechanics of the window gears.

The fuses are all intact. When I push the tail gate button or try the rear key (which is questionable at best)....nothing happens at all.

I wonder if the PO disconnected something so there would be no chance of lowering the plexiglass window.

Any ideas on how to trouble shoot this would be appreciated.

Thanks,

Doc

 

[Ming89FJ62]

Here's the schematic for the tailgate window.

https://forum.ih8mud.com/fj55-iron-...lgate-junction-block-toast-3.html#post3244405

There are no fuses for the tail gate window. There's a circuit breaker under the DS dash that receives power directly from the battery. It's very common for the interlock switch on the tail gate to not close completely - it's located on the DS side of the tailgate. The key switch is actually the master and should work with just the key. The dash switch has a relay in the circuit and requires that the ignition switch is in the ON position to raise or lower the window using the dash switch. There is also a small terminal strip in the tail gate where you can check for power with VOM meter - light blue w/ white tracer and light blue w/ black tracer depending on the key/switch position. Power is your first check - then move to the mechanical components.

 

[onemanarmy]

first thing i would do is take out the tailgate safety switch and splice the wires together. The switch is located on the drivers side, and is half way up the body where the tailgate meets the body. This was the cause of mine not working. Also, the window worked for a while, then the plastic gear broke and jammed the motor. Took it all apart, installed a new brass gear, lubed it up, and now its been trouble free. These are two easy to spot trouble areas.

 

[Pighead]

I love tailgate window problems.
The tailgate safety switch (mentioned above) delivers ground to the motor when the plunger is IN. It can be defeated in a couple of ways when working on the motor. A tie-wrap to hold the plunger in often works, or remove the switch and splice that wire together. There is also a little lever down in the linkage that prevents the window from moving down too far, but those hardly ever work anymore.
Take a good spare 12v battery to the tailgate, with some long jumper wire (good speaker wires work) and put 12 volts right to the motor and see what happens.
Or, it's the gear. take off the gear cover (3 or 4 phillips screws) and see how many pieces your gear is in...

 

[hindsight]

Here's the schematic for the tailgate window.

https://forum.ih8mud.com/fj55-iron-...lgate-junction-block-toast-3.html#post3244405

There are no fuses for the tail gate window. There's a circuit breaker under the DS dash that receives power directly from the battery. It's very common for the interlock switch on the tail gate to not close completely - it's located on the DS side of the tailgate. The key switch is actually the master and should work with just the key. The dash switch has a relay in the circuit and requires that the ignition switch is in the ON position to raise or lower the window using the dash switch. There is also a small terminal strip in the tail gate where you can check for power with VOM meter - light blue w/ white tracer and light blue w/ black tracer depending on the key/switch position. Power is your first check - then move to the mechanical components.

Thanks! I will give it a shot.

Doc

 

[hindsight]

The tailgate safety switch was the culprit. The front switch now actuates the motor....I can hear it running but the gears do not move. I assume that I am correct in guessing that the little plastic gear is probably toast.

If that is the case....where does one find a repalcement or the brass gears?

Doc

 

[Ming89FJ62]

The plastic gears are unobtanium and have been for a while. There are several members on the board that have similar gears machned from brass. You may want to try search for their names. There are two styles of gears depending on the year of the truck so make sure you get the correct one. Glad it was an easy troubleshoot.

 

[hindsight]

Here is why the widow will not actuate....no gear!

Doc

 

[Pighead]

That would explain it...

 

[3pits]

Hey Guys, thanks for the information.
I want to make sure I am clear here.
On my 78 pig, the black wire from the interlock/safety switch should be mated to the white wire with black stripe coming off the motor? or conversely I could bypass the safety interlock/switch by grounding the motor thru the white/black wire?

I pulled the entire motor/gear housing plate to get to the key operated relay/switch thinking that was the problem...

I will also pull the transmission cover to see what shape my gear is in and hope I can get the motor to actuate tomorrow...

 

[Ming89FJ62]

Correct. The white wire w/ black tracer normally goes from the safety interlock switch to the window motor providing the ground. If the interlock switch is toast or can't be adjusted to work you can just ground the white/black wire from the motor.

Fighting the window sure makes for a great afternoon.