4th Gen Tailgate won't open unless engine is on

[chippyip]

Really sad that after all the people took their time to help the OP, especially
JrAdrock80 who handed him the fix on a silver platter, that he couldn't at least come back and let everyone know the conclusion. Kind of like a one night stand. Got what he wanted and hit the road.

Agreed. You meant John619.... ? That was post on 06/08/2016

I have the same issue on my hatch now. Will check as JrAdrock80 did.

 

[importman]

Agreed. You meant John619.... ? That was post on 06/08/2016

I have the same issue on my hatch now. Will check as JrAdrock80 did.

That's correct. I guess it shouldn't bother me but I was brought up to say thank you when someone does something for you. But maybe it just slipped his mind. Good luck with yours.

 

[chippyip]

That's correct. I guess it shouldn't bother me but I was brought up to say thank you when someone does something for you. But maybe it just slipped his mind. Good luck with yours.

:drummer: I got my issue fixed. Very happy. I checked 12V both Blue and Blue/red wires on the hatch ECU as what JrAdrock80 did with ignition off. Blue wire checked 12V and Blue/Red checked 0 v. I traced the continuity of the Blue/Red and found it was broken inside the boot near the body and the hatch. I believed I broke it as I installed the backup cam by running the cam wires through the boot. Solder and shrink wrap it.

It is back to what the hatch lock, hatch window it supposed to work.

I have read many comments on this forum which is great but it can be better.

One thing I would like share with you all if you install a back up cam, it is important to keep all wires and connectors of the backup cam on the lock side of the hatch and it is clear for the window path going up and down. I made a mistake and broke one of wires of the backup cam when I tested the hatch window up and down.

Good luck.

 

[chippyip]

I had the exact same problem as you and you're in luck. I bet i know what the problem is........ I found a thread by pure accident after TWO YEARS of this issue. Tried everything that everyone suggested with normalizing and removing the negative battery connection overnight and nothing worked. I was close to taking it to the local Toyota mechanic to get it fixed, but I have built high performance vehicles, rally cars, resurrected junk yard cars, etc. and I will be damned if I was going to run to a mechanic with my tail between my legs on this.

So, I decided to try one more time and I took the hatch apart again. I looked at everything and came up short. I was pissed and in desperation I googled one more time and found a thread that I had never seen before. I cant even find it now, its like it was meant to be found and just disappear....... Weird.

Anyway, here is what the thread said........ Someone had the exact same issues you have and he tried everything, even swapping the rear body ECM. NOTHING! So he had a wiring diagram by chance an he noticed that the blue connector that goes into the body ecu mounted in the tailgate is supposed to be receiving 12 volts on the blue wire and also 12 volts on the blue/red wire with the ignition off. The blue wire was putting out the 12 volts, but the blue/red was 0 volts. He pulled the boot between the body of the 4Runner and the hatch up at the top of the hatch opening. It is the one on the left side when you open the hatch. He pulled the boot back and exposed the wires and there you can find the blue/red wire. He stuck the multi-meter probe in the wire and low and behold, 12 volts with the ignition off!

So I followed this and I tested the blue connector on my rig and the blue/red wire was metering 0 volts with the solid blue wire at 12 volts. I probed the wire up top and I had 12 volts. So I took the plate that holds the body ECM to the rear hatch off and after giving a little play on the wire loom up top of the hatch, I was able to pull the wire harness out a little further. This is when I noticed that the electrical tape wrap was all loose and unraveling. I unwrapped the tape and saw that the blue/red wire was kind of crushed/melted but the other wires were ok. I probed it at this point for continuity to the plug and continuity was good. On the other side of the break in the wire, I was probing 12 volts. I cut the wire and soldered in a new length of wire as a patch, about 3 inches, and heat shrunk some tube around the whole thing. Then i re-wrapped with tape. Checked the red/blue at the connector and had 12 volts! I was beyond excited at this point. Put the tailgate back together and HOLY SHHHHHHHHHHHHIIIIIIIIIP, it worked!!!!!! Key fob opened the window. Tailgate opened without the key on in the ignition, wiper and defrost work without rolling window down and then back up, auto up and down stays memorized and no more weird alarm operation after open and closing gate with key on!!!!!!

Now, I cant say yours will be that easy, but if you want to try something quick I would probe the power wires to the body ECM in the hatch. I can almost guarantee that is your problem. Hopefully you will not have to replace the wire way up in the hatch itself because you will have to fish it out. Yikes!

What it looks like happens here is that either the window or something in the hatch rubs the harness and eventually water gets into the tape causing it to unravel. The wire either gets pinched or rubs right around the base of the window (in my case) and eventually it wears a hole. The window gets water drainage past the seals and it drips down the harness. The wires become oxidized and corrode and break inside the wire itself. I came to this conclusion because once the wire was cut the copper was very oxidized like old pennies. This is just my theory but it seems like the probable cause.

I hope this helps you because it made me beyond happy. It cost me about an hour of my time and $0 to fix. I would have NEVER figured this out if it wasn't for that thread I found and I vow to help others with this problem because it drove me nuts for WAY to long.

Good luck and cheers,

Adam

Hi Adam, Thank you very much your sharing and I just fixed my broken Blue/Red wire of the hatch ECU. The hatch is back to normal. I posted in the threads.

 

[importman]

:drummer: I got my issue fixed. Very happy. I checked 12V both Blue and Blue/red wires on the hatch ECU as what JrAdrock80 did with ignition off. Blue wire checked 12V and Blue/Red checked 0 v. I traced the continuity of the Blue/Red and found it was broken inside the boot near the body and the hatch. I believed I broke it as I installed the backup cam by running the cam wires through the boot. Solder and shrink wrap it.

It is back to what the hatch lock, hatch window it supposed to work.

I have read many comments on this forum which is great but it can be better.

One thing I would like share with you all if you install a back up cam, it is important to keep all wires and connectors of the backup cam on the lock side of the hatch and it is clear for the window path going up and down. I made a mistake and broke one of wires of the backup cam when I tested the hatch window up and down.

Good luck.

That's great. Glad you got it fixed. Also glad you came and posted what you tested, how you fixed it, and gave the warning to others to help them avoid what happened to you. That's what was missing from the other poster. This board is a invaluable resource. I've gained a lot of information from others, and whenever there is a question that I know the answer to, I share it as well. I'm a lifelong ASE Master Tech so I can help with a fair amount of problems. But there are so many things I don't know, that I've learned from others on here. Like suspension questions, or "will these tires fit without rubbing", and known fixes like what JrAdrock80 posted which helped in your case. Thanks for posting your fix.

 

[bmass06]

4th Gen Tailgate will not open unless engine running!

:drummer: I got my issue fixed. Very happy. I checked 12V both Blue and Blue/red wires on the hatch ECU as what JrAdrock80 did with ignition off. Blue wire checked 12V and Blue/Red checked 0 v. I traced the continuity of the Blue/Red and found it was broken inside the boot near the body and the hatch. I believed I broke it as I installed the backup cam by running the cam wires through the boot. Solder and shrink wrap it.

It is back to what the hatch lock, hatch window it supposed to work.

I have read many comments on this forum which is great but it can be better.

One thing I would like share with you all if you install a back up cam, it is important to keep all wires and connectors of the backup cam on the lock side of the hatch and it is clear for the window path going up and down. I made a mistake and broke one of wires of the backup cam when I tested the hatch window up and down.

Good luck.

I have the same problem and you and JrAdrock80 were the only ones to come to a solution. BUT I pulled the blue connector off ECU-B, checked voltage on Blue/Red to ground and it was like 2VDC and would drop, same as when I checked Blue to ground. I was really hoping to see 12V on blue and nothing on Blue/red so I knew what the fix would be, but I didn't.

THEN I saw that if you reset ECU-B with pulling the fuse out for 10 seconds, put it back in, lock the car, unlock the car and the hatch works like normal but that didn't help me either so I am at a loss now... any ideas?

 

[bmass06]

I had the exact same problem as you and you're in luck. I bet i know what the problem is........ I found a thread by pure accident after TWO YEARS of this issue. Tried everything that everyone suggested with normalizing and removing the negative battery connection overnight and nothing worked. I was close to taking it to the local Toyota mechanic to get it fixed, but I have built high performance vehicles, rally cars, resurrected junk yard cars, etc. and I will be damned if I was going to run to a mechanic with my tail between my legs on this.

So, I decided to try one more time and I took the hatch apart again. I looked at everything and came up short. I was pissed and in desperation I googled one more time and found a thread that I had never seen before. I cant even find it now, its like it was meant to be found and just disappear....... Weird.

Anyway, here is what the thread said........ Someone had the exact same issues you have and he tried everything, even swapping the rear body ECM. NOTHING! So he had a wiring diagram by chance an he noticed that the blue connector that goes into the body ecu mounted in the tailgate is supposed to be receiving 12 volts on the blue wire and also 12 volts on the blue/red wire with the ignition off. The blue wire was putting out the 12 volts, but the blue/red was 0 volts. He pulled the boot between the body of the 4Runner and the hatch up at the top of the hatch opening. It is the one on the left side when you open the hatch. He pulled the boot back and exposed the wires and there you can find the blue/red wire. He stuck the multi-meter probe in the wire and low and behold, 12 volts with the ignition off!

So I followed this and I tested the blue connector on my rig and the blue/red wire was metering 0 volts with the solid blue wire at 12 volts. I probed the wire up top and I had 12 volts. So I took the plate that holds the body ECM to the rear hatch off and after giving a little play on the wire loom up top of the hatch, I was able to pull the wire harness out a little further. This is when I noticed that the electrical tape wrap was all loose and unraveling. I unwrapped the tape and saw that the blue/red wire was kind of crushed/melted but the other wires were ok. I probed it at this point for continuity to the plug and continuity was good. On the other side of the break in the wire, I was probing 12 volts. I cut the wire and soldered in a new length of wire as a patch, about 3 inches, and heat shrunk some tube around the whole thing. Then i re-wrapped with tape. Checked the red/blue at the connector and had 12 volts! I was beyond excited at this point. Put the tailgate back together and HOLY SHHHHHHHHHHHHIIIIIIIIIP, it worked!!!!!! Key fob opened the window. Tailgate opened without the key on in the ignition, wiper and defrost work without rolling window down and then back up, auto up and down stays memorized and no more weird alarm operation after open and closing gate with key on!!!!!!

Now, I cant say yours will be that easy, but if you want to try something quick I would probe the power wires to the body ECM in the hatch. I can almost guarantee that is your problem. Hopefully you will not have to replace the wire way up in the hatch itself because you will have to fish it out. Yikes!

What it looks like happens here is that either the window or something in the hatch rubs the harness and eventually water gets into the tape causing it to unravel. The wire either gets pinched or rubs right around the base of the window (in my case) and eventually it wears a hole. The window gets water drainage past the seals and it drips down the harness. The wires become oxidized and corrode and break inside the wire itself. I came to this conclusion because once the wire was cut the copper was very oxidized like old pennies. This is just my theory but it seems like the probable cause.

I hope this helps you because it made me beyond happy. It cost me about an hour of my time and $0 to fix. I would have NEVER figured this out if it wasn't for that thread I found and I vow to help others with this problem because it drove me nuts for WAY to long.

Good luck and cheers,

Adam

Hey Adam, thank you for writing this up. Mine only works with the engine on too. I tried what you did above but when I tested voltage on Blue I got maybe 2V then it would drop and the same would happen when I would test blue/red. I probed from the blue connector to a bolt on the hatch (hope that was accurate). When I pulled the back panel off everything was pretty clean and wire looms are intact. I didn't see any unraveling or broken/melted wire jackets I pulled on the blue and blue/red through the harness going into the body to check if it was broken or loose but didn't have any luck.

Also I tried resetting ECU-B which apparently fixed a lot of peoples hatch problems. Take out the 10A fuse for 10 sec, put it back in, lock, unlock the car and boom it worked with the engine off and no key. BUT still no luck with that.

If you have any more insight, any help would be appreciated!

 

[colio6]

:thanks:
I have a 5th gen, but exact same issue where no power to tailgate unless key turned on. Finally found some damage to a light blue wire where it runs up the side of the tailgate (after peeling off a lot of electrical tape). I've been dealing with this issue for 1.5 yrs, this post was the only one that describes the same issue. Thanks a bunch!

I had the exact same problem as you and you're in luck. I bet i know what the problem is........ I found a thread by pure accident after TWO YEARS of this issue. Tried everything that everyone suggested with normalizing and removing the negative battery connection overnight and nothing worked. I was close to taking it to the local Toyota mechanic to get it fixed, but I have built high performance vehicles, rally cars, resurrected junk yard cars, etc. and I will be damned if I was going to run to a mechanic with my tail between my legs on this.

So, I decided to try one more time and I took the hatch apart again. I looked at everything and came up short. I was pissed and in desperation I googled one more time and found a thread that I had never seen before. I cant even find it now, its like it was meant to be found and just disappear....... Weird.

Anyway, here is what the thread said........ Someone had the exact same issues you have and he tried everything, even swapping the rear body ECM. NOTHING! So he had a wiring diagram by chance an he noticed that the blue connector that goes into the body ecu mounted in the tailgate is supposed to be receiving 12 volts on the blue wire and also 12 volts on the blue/red wire with the ignition off. The blue wire was putting out the 12 volts, but the blue/red was 0 volts. He pulled the boot between the body of the 4Runner and the hatch up at the top of the hatch opening. It is the one on the left side when you open the hatch. He pulled the boot back and exposed the wires and there you can find the blue/red wire. He stuck the multi-meter probe in the wire and low and behold, 12 volts with the ignition off!

So I followed this and I tested the blue connector on my rig and the blue/red wire was metering 0 volts with the solid blue wire at 12 volts. I probed the wire up top and I had 12 volts. So I took the plate that holds the body ECM to the rear hatch off and after giving a little play on the wire loom up top of the hatch, I was able to pull the wire harness out a little further. This is when I noticed that the electrical tape wrap was all loose and unraveling. I unwrapped the tape and saw that the blue/red wire was kind of crushed/melted but the other wires were ok. I probed it at this point for continuity to the plug and continuity was good. On the other side of the break in the wire, I was probing 12 volts. I cut the wire and soldered in a new length of wire as a patch, about 3 inches, and heat shrunk some tube around the whole thing. Then i re-wrapped with tape. Checked the red/blue at the connector and had 12 volts! I was beyond excited at this point. Put the tailgate back together and HOLY SHHHHHHHHHHHHIIIIIIIIIP, it worked!!!!!! Key fob opened the window. Tailgate opened without the key on in the ignition, wiper and defrost work without rolling window down and then back up, auto up and down stays memorized and no more weird alarm operation after open and closing gate with key on!!!!!!

Now, I cant say yours will be that easy, but if you want to try something quick I would probe the power wires to the body ECM in the hatch. I can almost guarantee that is your problem. Hopefully you will not have to replace the wire way up in the hatch itself because you will have to fish it out. Yikes!

What it looks like happens here is that either the window or something in the hatch rubs the harness and eventually water gets into the tape causing it to unravel. The wire either gets pinched or rubs right around the base of the window (in my case) and eventually it wears a hole. The window gets water drainage past the seals and it drips down the harness. The wires become oxidized and corrode and break inside the wire itself. I came to this conclusion because once the wire was cut the copper was very oxidized like old pennies. This is just my theory but it seems like the probable cause.

I hope this helps you because it made me beyond happy. It cost me about an hour of my time and $0 to fix. I would have NEVER figured this out if it wasn't for that thread I found and I vow to help others with this problem because it drove me nuts for WAY to long.

Good luck and cheers,

Adam