: Rear Liftgate won't function automatically
06-05-2009, 10:34 AM
I own a 2004 Infiniti QX56. The remote will not open/close the rear liftgate (the remote works fine for locking/unlocking the car). The switch by the driver, the switch on the upper left back liftgate (Open/Cancel) and the switch under the license plate will not operate the liftgate. The switch under the licence plate does unlock the liftgate but it has to be raised/lowered manually. The door locks, automatic windows and rear left/right widows function normally. I was told by a dealer that the Back Door Control Unit is bad. Befroe I spend $1300 I wanted to check a couple of things myself. Does anyone know where the circuit breaker/fuse is that powers the Back Door Control Unit? (under the hood (which one?), passenger side, etc.) and where is the Back Door Control Unit? I wanted to check the wiring connections to that unit. Any suggestions would be greatly appreciated.
06-05-2009, 03:11 PM
Welcome to CA LCWB1979!
I actually do not have the auto liftgate, so hopefully one of the members who do will chime in soon. I do recall a post here talking about it though! So if I find it, I'l post it.
06-05-2009, 04:46 PM
Have you considered replacing the battery on the remote? Not sure if this will help...since other fundtions of the remote work. How about holding down the liftgate button for several seconds longer?
06-05-2009, 06:36 PM
Thank you for the suggestions. I tried both previously with no success. None of the other buttons work either. It is like there is no power to the Back Door Control Unit which is what I am trying to verify.
06-06-2009, 12:33 PM
does the liftgate work from the in-cab switch, and the back pillar switch?? Just not the key fob?
06-06-2009, 02:58 PM
No, none of the switches will operate the rear liftgate.
06-06-2009, 05:20 PM
That narrows it down to the unit itself, have you checked all fuses? I had a bad actuater a few years ago (repaired under warranty), so I'm not exactly sure what they replaced. I'll see if I can find the paper work.
06-06-2009, 06:04 PM
This may sound crazy but make sure ur window on ur tailgate didn't accidentally get popped open.i had the same problem and thats what it was.
06-07-2009, 12:29 AM
No, that doesn't sopund crazy. The auto lift function will not work if the rear window is open. I checked that and it is completely closed.
06-07-2009, 03:21 AM
Sorry my friend thats all i got...............
06-07-2009, 10:43 AM
When you try to open it, can you hear the actuator cycling? By that, I mean the mechanism that locks the door shut.
06-07-2009, 11:04 AM
Nothing happens at all with the liftgate or the latch/locking mechanism when I use the remote (I know the remote is good) or any of the in-vehicle switches. I'm 99% convinced it is a fuse. I don't know which one or where it is located.
Hope someone has the solution. I just encountered the exact same problem with my 07 Armada today. In addition, I cannot open the hatch window at all.
06-24-2009, 08:57 AM
same problem as mine before until now i have still the same problem because my warranty expires. i bought them to the dealer and they replace the motor and latch but it goes back every winter times.
06-24-2009, 02:27 PM
Welcome to CA dave!
I see yours is an 07, is it still under the warranty? Because if it is, please take it in.
The hatch window was ajar. A friend pushed really hard on one corner and I could hear it "pop" shut. Everything works fine now. Thanks.
06-25-2009, 09:41 AM
Glad it was an easy catch.
02-19-2013, 06:22 PM
I just bought a 2012 Armada that was a GM demo. I noticed that the rear liftgate is sensitive and sometimes the auto entry works and sometimes it doesn't. It is especially bad when the car has been sitting overnight - I will hold the button and I will hear a beeping coming from the car but it won't open. The beeping will continue for a while after I am driving. Then when I get where I am going it suddenly works.
I just picked it up from the dealer after having been there for 8 days (I've only had the car for 3 weeks!) and they replaced the door motor, but I am not convinced it has fixed the problem. It still seems to be sensitive, so not sure if anyone else has any ideas. I don't want to leave it there another week so maybe I can get an idea of what else it might be? Thanks!
I have your solution....I was having problem with my 07 QX56 and brought it into the dealership. My rear glass would "pop" on its own and the power lift gate would work sometimes.
The dealership had to replace the whole rear wiring harness which is all connected to the motor and sensor. Replace and works like new. The wiring harness also includes the rear window switch and the tail gate switch.
Hope this helps.
01-24-2015, 07:32 PM
I know this is an old thread. However, after reading all I could and trying every solution mentioned, my final solution turned out to be completely different, even though I had very similar symptoms. I thought I'd share that solution in case anyone else stumbles across this thread looking for answers.
My symptoms were that the opening function was very intermittent and that intermittency seemed related to relative moisture or temperature. Worse in winter, better in summer. In addition, I could only open it from the back handle. The FOB and driver switch had no effect (not even a ding). When open, I could only close it manually. Again driver switch and FOB (as well as the back close switch) had no effect.
My earlier life as an electronic technician prompted me to start doing continuity tests on the harness. Sure enough the two right-most connectors (at the outside edge of the tailgate) were intermittent. These are the connectors that ultimately wind their way through the tailgate and terminate at the dreaded Gate Control Module deep in the bowels of the right rear quarter-panel. Looking at the pins in the connectors revealed a dark coloration on what should be clean aluminum.
A little contact cleaner spray from Radio Trash, directed at both the male and female connectors, and the problem was solved.
The recommendation then, before you start shot-gunning parts, is to pull apart every connector you can find in the rear, clean the contacts and firmly seat them back together. This is particularly the case if your symptoms are intermittent, or appear to change with temperature or humidity.
If you take it to a dealer, they will be more than happy to replace the entire wiring harness and charge you accordingly.