HELP!!! Rear Tailgate, Cruise Control Issues

[jhuerta22]

Since my little fender bender, I've had issues with the rear wiper, defogger, rear window, and cruise control. Some days they work and I have no problems, other days I have nothing. One day while driving they would work until I would drive around right curves in the road.

It's NOT the window lock, it's NOT a fuse, and checking the wiring harness between the body and the hatch and there is some cracked insulation on the wiring, but it's been covered since before I've owned the vehicle. Would that cause my problems? I'm at a loss. I believe it's a wiring issue. I just don't know where at, and reading wiring schematics is a bit of a weak point for me. I'm hoping someone can point me in the right direction.

Thank you,
Huerta

 

[greenbomer]

Maybe a bad ground

 

[IBallEngineer]

Since my little fender bender, I've had issues with the rear wiper, defogger, rear window, and cruise control. Some days they work and I have no problems, other days I have nothing. One day while driving they would work until I would drive around right curves in the road.

It's NOT the window lock, it's NOT a fuse, and checking the wiring harness between the body and the hatch and there is some cracked insulation on the wiring, but it's been covered since before I've owned the vehicle. Would that cause my problems? I'm at a loss. I believe it's a wiring issue. I just don't know where at, and reading wiring schematics is a bit of a weak point for me. I'm hoping someone can point me in the right direction.

Thank you,
Huerta

There is no single fuse for all those systems, so you are correct, it is not a fuse. With the exception of the cruise control, all the other systems are in the back door. And there is a connector that affects all those systems, not just the harness can be a problem, but the connector itself.

The rear window and wiper are connected to the Back door ECU, which is in the door. The defroster is operated by the Body ECU, which is in the dash.

The ground point for the wiper motor and Back door ECU is in the left 1/4 panel area.

I would start with the "connection" to the back door. Then I would double check the connection. If that didn't work, I'd TRIPLE check that connection. If that still doesn't work. Call me!

opcorn:

 

[jhuerta22]

With the power switching on and off like that, is there any possibility of it being a bad ground?

 

[IBallEngineer]

With the power switching on and off like that, is there any possibility of it being a bad ground?

Of course, well actually a "poor" ground. If it intermittently makes a good contact then loses it. I'm not thinking it's anything but the connector though.

Did I mention the connector?

 

[jhuerta22]

Of course, well actually a "poor" ground. If it intermittently makes a good contact then loses it. I'm not thinking it's anything but the connector though.

Did I mention the connector?

Hahaha! I gotcha. So it's more than likely the connector in the tailgate. Would using contact cleaner be the first step? When looking at the connector all the wires look like they're in good shape and they're all snuggly in place. Dirty contact points?

 

[IBallEngineer]

Hahaha! I gotcha. So it's more than likely the connector in the tailgate. Would using contact cleaner be the first step? When looking at the connector all the wires look like they're in good shape and they're all snuggly in place. Dirty contact points?

I've never actually seen the connector, but it is INSIDE the body, not in the tailgate. The issue may be corrosion, it may just not be connected properly. The consensus here is that it is prone to bad connection by design. And if you read enough threads about rear door problems, the connection has been the fault the majority of the time. If you check the connector and it is not dirty or damaged, and is connected properly. We can check individual wires for power and ground if you have a multi-meter.

Did I mention the connector?

 

[TXLX1]

I have a back door ECU and harness that came off a 99 door if you need it (shipping cost only). Just shoot me a PM and I can send you picture.

 

[mckennar]

Of course, well actually a "poor" ground. If it intermittently makes a good contact then loses it. I'm not thinking it's anything but the connector though.

Did I mention the connector?

In another car I had a ground (for a hall effect sensor) that went from the distributor to the firewall that had separated but was hanging down via gravity juuuust right so that the car would start and run... but whenever you tried to accelerate or take a corner, the car would cut out due to the loose ground disconnecting from the distributor side thanks to g-forces.

Sounds like something similar could be happening in the OP's rig. Where possibly the wire broke away from the connector but is close enough to intermittently make connection but when he turns the wire gets disconnected?

Something about a connector?

 

[jhuerta22]

I've never actually seen the connector, but it is INSIDE the body, not in the tailgate. The issue may be corrosion, it may just not be connected properly. The consensus here is that it is prone to bad connection by design. And if you read enough threads about rear door problems, the connection has been the fault the majority of the time. If you check the connector and it is not dirty or damaged, and is connected properly. We can check individual wires for power and ground if you have a multi-meter.

Did I mention the connector?

I believe you have mentioned the connector, but I'll keep it in mind! Hahaha! So the location of the connector IN the body is what I need to find. I guess I'll see what I can tear apart and find and I'll get back with info/pics soon!

 

[gamefreakgc]

I believe you have mentioned the connector, but I'll keep it in mind! Hahaha! So the location of the connector IN the body is what I need to find. I guess I'll see what I can tear apart and find and I'll get back with info/pics soon!

It's actually pretty easy to access. Just remove the fabric strap from the back panel on the interior of the door (little cover pops off) and then yank the whole panel off. A few clips might break, FYI. Then take off the larger black access panel and you are in. the wiring will be right below the window and connects in the corner of the hatch on the driver's side before it squeezes up the side of the rear hatch and through the rubber tube and into the headliner. There's a second connector up there behind the headliner but highly doubt that would be the issue.

 

[jhuerta22]

It's actually pretty easy to access. Just remove the fabric strap from the back panel on the interior of the door (little cover pops off) and then yank the whole panel off. A few clips might break, FYI. Then take off the larger black access panel and you are in. the wiring will be right below the window and connects in the corner of the hatch on the driver's side before it squeezes up the side of the rear hatch and through the rubber tube and into the headliner. There's a second connector up there behind the headliner but highly doubt that would be the issue.

What I'm gathering from the other posts here is that the issue exists in the body itself and not in the liftgate. I've checked the connections in the liftgate and visually they all look intact. I know that there's some cracked insulation on a few wires in the harness between the liftgate and body. After that, I'm not sure what the connection looks like.

 

[gamefreakgc]

What I'm gathering from the other posts here is that the issue exists in the body itself and not in the liftgate. I've checked the connections in the liftgate and visually they all look intact. I know that there's some cracked insulation on a few wires in the harness between the liftgate and body. After that, I'm not sure what the connection looks like.

Gotcha. The next connector that I know of is just behind the driver's side headliner just inside the vehicle from the rear hatch. To get to that one you need to remove the rear cargo dome light, top trim piece (pops out), the two 10 mm bolts you just uncovered, bottom trim piece (4 screws I think), then the driver's side cargo body panel. That should be enough for you to peek between the headliner and the frame to see it. If you have to remove the headliner to get to it... good luck not damaging the headliner or breaking clips

 

[jhuerta22]

good luck not damaging the headliner or breaking clips

Hahaha, much appreciated. I've removed the panels a few times for a project, and a few have already broken. I guess I should have the epoxy ready!

 

[jhuerta22]

Problem solved. So, even having the panel off three or four times in the past two years, I NEVER noticed a ground that wasn't connected. The PO wired in a trailer harness and never reattached the ground. It must have been making contact until after my fender bender. Hahaha! I had a feeling! Well, I connected it, and everything worked! Then, we disconnected it, and all the similar problems started again. Looks like I found my solution. Thanks for the help and suggestions!

- Huerta

 

[IBallEngineer]

Problem solved. So, even having the panel off three or four times in the past two years, I NEVER noticed a ground that wasn't connected. The PO wired in a trailer harness and never reattached the ground. It must have been making contact until after my fender bender. Hahaha! I had a feeling! Well, I connected it, and everything worked! Then, we disconnected it, and all the similar problems started again. Looks like I found my solution. Thanks for the help and suggestions!

- Huerta

Where was that ground? Post pictures so people reading this thread can benefit!

 

[jhuerta22]

This isn't the picture of my 4Runner, as I didn't snap any pictures of it. (Had about 30 minutes to get it fixed) I did, however, find a picture of what I was talking about. The picture shows where the ground can be found, and there's even a loose terminal in the picture in the same location as the one I had found. I believe the loose ground in the picture is for installing a trailer plug. The loose one I found was in the same location, just not bolted onto the body.