Rear Door / Liftgate issues

[BleedingCoffee]

Hi,

I have a 2013 QX56 and am having issues with the rear door/liftgate.

Issue: The button on the door, the button on the dash or the key fob don't work. The door actuator also won't latch when closing the door manually.

Summary:
1. Dash switch is set to on
2. Checked fuses, all good - none blown.
3. Replaced the actuator and motor - still doesn't work. Put originals back.
4. Brought to dealership, they said there was a code (wouldn't tell me what code). They cleared the code and it started working again. The code wasn't showing up on my reader.
5. Worked for 2 months, and now it did it again. Did the same checks (minus replacing actuator and motor again)
6. I couldn't find the factory service manual for the Doors and Locks for the 2013, but I did find it on here for the 2014 (assuming it's close to the same?)

My current thoughts is that it is the Rear Tailgate Power Control Module. I can't figure out the part number for this; I have done a bunch of searches, and only finding part numbers for newer model years. Based on the 2014 manual I believe this is behind the luggage side lower finisher panel.

Does anyone know the right part number and suggestion for this? Thoughts or suggestions on path forward??

Thanks!

[VStar650CL]

The controller for the hatch is part of the lift motor assembly. Part number for a '13 would be 90560-1V81A or -1V81B.

[BleedingCoffee]

Hmm….. Since I’ve already tried swapping out the whole lift motor assembly, and all components don’t seem to be working I’m not sure where to look next…. Any thoughts? I feel I’ve tried the entire system, but feel like I’m missing something.

[VStar650CL]

The diagnostics for those systems frankly suck, but the door not latching is probably a clue. If you haven't replaced the latch, try that next. The hatch controller runs that, and there are microswitches in the latch mechanism which often cause misbehaviors and failures. Of course check the wiring while you're in there and make sure your problem isn't from water intrusion or corrosion.

The whole power hatch setup in the QX56/QX80/Armada never changed much from the day it came out, so the only differences in the '14 FSM might be wire colors. Maybe not even that.

[BleedingCoffee]

Well, I had already tried that latch/actuator and no difference. Wiring in the rear panel all looked clean and good, no signs of water or corrosion. Any other thoughts?

[VStar650CL]

The only thing in the way of components that you haven't replaced is the pinch sensors, and those rarely cause issues unless there are broken wires. It sounds like you're looking at a wiring or pin-fit issue, but it would really help to know what code they cleared to wake the controller back up. I'd insist that they pull the file and give you a copy of the code sheet. You paid for the diag, and under law in most states that makes the documentation your property as much as theirs. You're entitled to it if you request it.

[BleedingCoffee]

Thanks - I gave the a call and they said they didn't keep a record of the codes specifically, only that they cleared 2 codes. Those codes were cleared 2-3 months ago when I first had this issue before it resurfaced a few days ago. I am thinking I may need to tear the panels down again and look through the wiring closely again. Where are the pinch sensors? Do you think it could be something wrong with the master power switch for the door on the dash? My hesitation on the switch not being an issue is that the door won't manually close either.

[VStar650CL]

The pinch sensors are a pair of strips located on the edge of the hatch on either side. They're basically odd-shaped grounding switches, they're each connected to a pullup resistor inside the hatch controller and overpower the pullup to ground when something pinches them. I doubt that's the problem unless maybe one of them is shorted. The controller can't detect that, it can only detect an open circuit to cause a code. Since you had codes the last time, it seems dubious that the pinches are causing your issue.

There's a microswitch called the "half latch" inside the latch assembly which frankly causes about 90% of the problems we see with Nissan latches. It detects when the latch cam contacts the striker but isn't fully closed yet. Then the controller runs the cinch motor until a separate "closed" switch tells it the cam is fully rolled over and the hatch is shut. Without a working half latch, the door becomes paralyzed. So even if it's a wiring problem, I'd expect to find it someplace in the hatch umbilical or right at the latch assembly. However, before you throw anymore parts at it, I'd suggest getting the dealer to scan the ABD and insist on a printed copy of the scan. Since they didn't actually "fix" it the last time, if you make a stink, they may just scan it free to get you out of their hair. No service manager or tech likes a "comeback".