1st Gen auto. ECT solenoid #3 wired through rear Window Lock switch?!

[flagbasher]

When I bought my 4Runner, one of the things I noticed that needed to be replaced was the rear Window Lock switch.

On the console between the rear Wash/Wiper switch and the rear Window Up/Down switch is the rear Window Lock switch.

The face of the button is broken off. The button will go down, but not come up without being pulled. It still seems to switch and makes the rear Window Up/Down switch enable and disable as expected, but it doesn't automatically return to the up position, so I bought a used rear Window Lock switch to replace my broken one.

Seems easy enough, right? Wrong.

As soon as I pulled the console apart, I noticed the wiring had been hacked into. The yellow wire coming from the harness under the radio and to the auto tranny ECT computer's solenoid #3 pin 10/24 is cut, and each end of that is now run through the rear Window Lock switch.

The rear Window Lock switch has 4 wires on it. Blue, yellow, red, and green. The blue/yellow wires are the ones that switch when I test my new switch with a meter. The blue/yellow wires from the rear Window Lock switch in my truck are currently cut and are connected to the ECT solenoid #3 circuit. They were severed from the rear Window Lock switch harness and are fed to the ECT instead.

On the far side of where the blue/yellow rear Window Lock switch wires SHOULD go, the wires on the other side are now spliced together.

Seems like, when the rear window is locked, the ETC solenoid #3 circuit will also be broken.

Is there a reason why somebody might do this?

Thanks in advance for any help you might provide. :keyboard:

Wiring diagrams.

 

[flagbasher]

So I've read that, if the ECT computer is disconnected, the transmission defaults to a manual shifting mode where you jump from L to 2 to D.

I wonder if this is a theft deterrent hack. Someone breaks in when the ECT is disconnected, they put it in D, and the car just bogs and they don't know about the manual shifting mode.

That's all I've got.

 

[RAD4Runner]

Yeah, quite possibly a theft deterrent "mod" if done cleanly.
If wiring is dirty, call it a "hack" - LOL!

 

[flagbasher]

At least this particular wiring modification was done with crimps instead of twisted wires and electrical tape.

Tonight, I think I'm going to try reverting the wiring to its original state. I'm going to solder and heat shrink the ECT wiring harness connection for sure.

The splice on the original rear Window Lock harness that was spliced together was done with a special connector type that I think I can simply remove without having to do anything else. There will be some cuts in the wire, but the wire shouldn't be exposed. I guess we'll see about that one...

Then I can just drop the "new" switch in and everything SHOULD work. In a perfect world at least.

I can't keep the anti-theft mod because I don't want to hack up the new switch, and because I eventually plan to swap to a manual transmission and that mod wouldn't work anymore anyway.

 

[flagbasher]

So, yes, suspicions confirmed.

I hooked the ECT wires back together, put in the new rear Window Lock switch and everything works as expected.

So, if you follow my instructions in reverse, this thread is a tutorial on how to install a crappy rear Window Lock switch in your truck that doubles as a switch to ECT manual mode.

 

[KidVermicious]

I dunno why you'd do that though. I guess because that wire is convenient, but who says "yes I think it's a good idea for a thief to think this truck is gutless while he's driving it away instead of not being able to drive it away at all". That's a cool idea if he'd run a relay to the ignition wire through there or something.