Rear hatch still stuck!!

[jlach993]

That’s frustrating. I too hate throwing in the towel and going to a dealer, especially after putting in so much effort.

Hoping someone else can check my theory below to see if it makes sense:

Looking back at the circuit diagram, if the upper switch has power and is tripping the tailgate ajar circuit, looks like there is only two possibilities for the actuator not firing, both along line “M” in the circuit diagram: (1) There appears to be a splice junction (SJ255S - at least I’m guessing that’s what it is) on the ground side of the actuator - the actuator motor, door ajar circuit, and lower door switch all seem to join at that splice joint and then share a common ground after that point. Since the door ajar circuit and lower tailgate switch are working, the ground after the splice must be in tact. So maybe just that one leg from the actuator to the splice joint has come loose. The ground connection appears to be someplace in that tailgate area, so the splice must be back there too. (2) The wiring from the BCM to the actuator motor. Nothing else appears to be on that leg, and there is only a single connector between the actuator and the BCM. This connector is C3007/C3008 below the drivers seat. It’s shown “Detail E” of the connector quick reference that I posted earlier.

Can you check for a 12V pulse at the actuator harness when you press the upper tailgate switch using a known good ground? If you are getting voltage, then the problem must be ground side. If no voltage, then the problem should be on the wiring from the BCM. Or maybe test for continuity between the ground pin on the harness and a known good ground (or the actual ground connection for the harness C2700S-1 if you can access).

If no voltage to the harness, then the same type of test at that underseat connection.

Just brainstorming on the fly here. Hope it helps, and maybe others have better ideas.

hey man you've been a great help. Thanks for taking the time out and guiding me. Ill check those things out and report back tomorrow. I took a day off fiddling with the rover....just looking at it upsets me lol

 

[jlach993]

So i found out that theres no voltage going to the actuator when i test the pins of the connector going into it. I traced wiring using the wiring diagram and haven’t noticed anything chaffed or shorted. I checked the grounds and all seem tight. I discovered however that there are two relays for the tailgate also in the fuse box. I’m guessing one is for the upper and one for the lower tailgate. I cannot remove the relay at all. It’s in a tight awkward position and it’s impossible. Ill have to take apart the cabin a little to gain access to the relay. That’s the only thing thats left. Ill update once i switch the relays.

 

[jlglr4]

On the wiring diagram, it’s labeled as a FET (MOSFET). If that’s true, it might be an integral piece of the module and not removable. I also don’t think that’s a likely failure point - solid state device, no moving parts.

When you checked voltage at the actuator, what did you use as a ground point? If you used the ground pin in the same connector, I don’t think you can tell if the problem is on the voltage side (BCM signal) or the ground side.

If you used a good ground and still no voltage, then maybe check for voltage at the connection under the seat (again - using good ground)? Might narrow down the location of the problem.

Also, did you verify that valet mode did not somehow get switched on? I’ve never used it, so I don’t know how it’s turned on/off. But I guess it would lock up your glove box, right?

Hopefully someone else can weigh in on this problem - at least give me a sanity check on the above.

 

[sbojangles]

I recently started having trouble with the upper tailgate as well with very similar symptoms... fault on the GAP tool it's "B12EE-11 (68) Liftgate/tailgate/trunk release - General electrical failure - circuit short to ground"

Would it make sense for me to replace the actuator with this fault code or troubleshoot connectors/voltages?

 

[jlglr4]

I think it would be worthwhile to investigate your circuit, at least briefly, before paying for a new actuator. Probably just a two pin connector, so using an ohmmeter, unplug the actuator and test the pins on the wiring harness against a good chassis ground. I believe you should see an open connection to a chassis ground point on one pin and absolute resistance (no connection) to chassis ground on the other. If you have an open connection to ground on both pins, then there is a short to ground in the circuit outside the actuator mechanism.

The other test you could run is connect your voltmeter to both pins on the chassis and see if you get a 12v pulse when you hit the tailgate switch. Might need to clear your fault code first as I’m not sure if the fault code will prevent the BCM from delivering a voltage.

If the circuit looks good, then replace the actuator and clear the fault code (again - fault code might prevent the BCM from firing a signal - not sure).

When my actuator went bad, it didn’t through any fault codes. I just noticed it wasn’t reliably opening and eventually, if I hit it a few times in a row, it would get weaker with each trip of the switch. I believe that’s the most common failure symptom on the actuator, though it could perhaps generate a short in the actuator itself.

 

[jlach993]

On the wiring diagram, it’s labeled as a FET (MOSFET). If that’s true, it might be an integral piece of the module and not removable. I also don’t think that’s a likely failure point - solid state device, no moving parts.

When you checked voltage at the actuator, what did you use as a ground point? If you used the ground pin in the same connector, I don’t think you can tell if the problem is on the voltage side (BCM signal) or the ground side.

If you used a good ground and still no voltage, then maybe check for voltage at the connection under the seat (again - using good ground)? Might narrow down the location of the problem.

Also, did you verify that valet mode did not somehow get switched on? I’ve never used it, so I don’t know how it’s turned on/off. But I guess it would lock up your glove box, right?

Hopefully someone else can weigh in on this problem - at least give me a sanity check on the above.

So....upon hooking the truck up to a diagnostic tool that read modules for rovers...I discovered the same code for the tailgate as the poster above. Once i reset it and turned the truck on and off, i went to the back and grabbed the switch. BAM power.

 

[jlach993]

I recently started having trouble with the upper tailgate as well with very similar symptoms... fault on the GAP tool it's "B12EE-11 (68) Liftgate/tailgate/trunk release - General electrical failure - circuit short to ground"

Would it make sense for me to replace the actuator with this fault code or troubleshoot connectors/voltages?

So like mine, eventually the actuator will fail. New actuator and reset the code and all should be well for you.

 

[jlglr4]

That’s great news and good info for the rest of us. I hadn’t thought of the fault code causing the issue until sbojangles mentioned it in his post. The actuator must sometimes create an internal short when it fails, triggering the fault code to protect the BCM.

 

[cperez]

I also found that clearing the code with IIDTool gave me another brief shot at using the switch. In my case I could hear the wheezing puny sounds the actuator was making so I just replaced it and everything was fine. I am not skilled at voltmeters and ohm meters so I decided to just throw parts at the problem.

 

[jlach993]

Yeah so most just replace their actuators and it works fine, but rarely......like in my case do you need to read and clear the fault code on the BCM to get the new actuator working again.