Will your FOB lock & unlock the rear liftgate?
OK, so I just went out and tried it on my '08 LT.
The LT has the DIC display in the dash so it may alert slightly differently from the base unit if thatās what you have.
On mine, I open the gate and get in, no seatbelt and then start the engine in Park.
It dings 4 times like normal followed immediately by 5 more rapid dings and a message- rear liftgate open.
It makes no further alarms if I go into drive or reverse, or if I drive away with the liftgate open.
Does your TB at least ding when you start the engine if no seatbelt applied? Just trying to ensure the alarm is working at all. It should also ding if the engine off but key left in and door openedā¦
When I open the liftgate there icon lights up on the dash.
Yes, the car dings when there is no seatbelt and when the key is left in the ignition
OK, so the LGM is detecting devices connected to it and able to transmit serial communications to the BCM. If the FOB unlocks the gate, that means it also receives serial commands from the BCM but that may be academic at this point. Next step is to measure the voltages on the wiper motorā¦
I put a multimeter in the connector where it goes to the motor. One is 14.95v and the green wire is -0.066. I also did notice that the rubber trimming to the lift gate has a hole in it. I had went to the car wash yesterday and noticed water entering the trunk. There is a wet spot right next to the light lamp there. So that light is not working. I donāt know if that is cause for concern in regards to the wires connected to the motor. But something I wanted to add there.
Itās not good to have water entering there but as to whether or not it has caused any issues versus some other failure reason will need additional testing.
For the wiper motor measurements, they need to be done with the motor connected. This will allow you to accurately determine if the LGM is properly grounding the motor. If not connected, that pin is floating and may not read correctly. With the control set to turn on the rear wiper, back probe the C connection from the schematic above. Should read +12V nominal. Then back probe the E connection, should be close to ground. If it reads +12V, the LGM isnāt working correctly. Be sure to check the A connection for ground as well.
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So Iāve come across an interesting dilemma. My friend tried to install a camera in my car. Before the installation, the lift gate unlocked and worked normally. After he installed some wires in the fuse box behind the driverās side, the lift gate no longer opens. He reverted the fuses to before the installation and had the same issue. All the fuses were tested as working. Any ideas?
Also, I still never got the wiper motor working after all this time.
I would also like to point out that the lift gate has its panels so I can only access anything through a hole which I found out through a tutorial on youtube. Unfortunately, I was unsuccessful to open the lift gate. I am unsure if the dealer or who to look for in seeing if I can get this issue fixed. My friend is taking blame for this so he is willing to pay for the service. I just need an idea of where to look.
Yes, stop letting friends and back yard mechanics work on your vehicle, you seem to have very bad luck when doing soā¦
Find a real shop to repair your vehicleā¦
You might want to look for an automotive electrical shop at this pointā¦
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You did what is described in this youtube and it still wonāt open?
There a few fuses of interest. Some are in the under hood box and some are in the rear box under the back seat.
Under hood
IGN 1 fuse 16 feeds the BCM
Battery fuse 48 feeds the rear LGM
Rear fuse box
Power latch fuse 19
Lift gate module fuse 3
The last few months Iāve been taking my truck to a pro for repairs.
The camera was my fault for letting him do it but he had made a clean install in his car so I gave him the chance. Either way, yes Iāve had bad luck but at least Iām willing to keep trying to fix it.
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We checked the rear fuse box but not under the hood
Suggest to address @TwinTurbo 's ideas above; i.e. What problems did you encounter following the manual open procedure as described in the vdo? Do you know how to check fuses? If so, are all of the fuses TT mentions above good?
BTW, your thread is getting pretty long and hard to follow. You might get better help here by starting a new thread with just the current problems you are trying to solve and current status.
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Seems like the liftgate wiring was never repaired: no rear wiper, no power lock/unlock.
After manually unlocking the latch through the access hole in the trim panel, you should be able to open the liftgate using the exterior handle.
I didnāt know. I will start a new thread. Thank you.
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I have started a new thread. Sorry for the long thread on this one.