e70 auto liftgate problem
 

Hello everyone:

My 2009 e70 diesel liftgate was acting up and now is getting progressively worse. Trying to troubleshoot myself as much as possible because I think this type of situation could cost a ton at a dealer out-of-warranty. Done a TON of research on different forums .. nothing seems to match my symptoms .. really hoping to get new information and help from the awesome members here

Problem 1: Lift gate doesn't close with the button on the lift gate. (Original problem)
Symptoms: There is a clicking sound near the lid's latch that repeats every so often. Sometimes every 10-15 seconds to every 45 seconds while the lift gate is open.

Problem 2: Liftgate sometimes opens randomly while driving at low speeds (at stop or near stop). Hasn't been a hazard yet --> if it opens while driving at higher speeds I would definitely take to a dealer immediately.

Problem 3: Liftgate appears to not open to maximum height even with the idrive settings to top-most level.

Things I've tried:
-Slamming the lower lid.
-ensuring the keys are not in my pockets so I know the random opening isn't my fault

Yet to try:
-Battery does not appear to have been changed according to service records. I will get my hands on a multimeter to check voltage. What should it read?
-Hitting the relay or replacing it - dont' know where the relay is - anyone know?

THanks in advance.. going crazy here

OK.. update. So after fiddling with it some more, I think I've pinpointed the source of the problem. It's related to the wire harness on the right side of the boot lid.

By simply manipulating the rubber boot and the wires inside it, I was able to recover normal operation.

However, visually I see no damages to the wires, and even worse, the problem can come back. When the boot lid is completely open, if I keep manipulating the wires/rubber boot, eventually the lid can close without my pushing the button.

Anyone have a similar issue?

Sounds like you got pretty good steps to replicate the problem. Is the car still under warranty? Then take it to the dealer and let them fix it (i.e. throw parts at it).

Just a guess: water leaked inside and corroded wires/connectors.

OK - I have a little of the same - Upon opening, the liftgate will click 2-3 times then open. On occasion, I will click a few more times and if I help it unlatch, it opens normally. It closes fine.

ANY SUGGESTIONS?

No warranty :(

It's possible unfortunately visually i just can't see where the damage is done. I feel like the only way to be sure is to open up the lid and examine the wire all the way into the underside of the roof.

And if it still all "looks" good, the only way to solve the problem is to replace the wire harness, which is $250 to buy and tons of labor to replace

Your situation is slightly different from mine. Mine never clicked several times before opening. It opened fine but had issues closing.

In 2011 BMW issued a service bulletin for liftgate operation problems due to damaged wiring. Ask your dealer to check SIB 51-26-10.

Unfortunately this probably won't change the prognosis, but it might help you figure out where to look. If you can trace the wiring to wherever it's damaged, you might get away with splicing it and not having to replace the harness.

On BMW sedans, it is common for the wires between the body and trunk lid to fatigue from the constant flexing. The wires either completely break in half (obvious) or break internally (wire insulation still intact). The symptoms are similar to what you are describing. I am not sure how the wiring is run in the E70 as I have not had mine that long. But, you should check all liftgate wiring for continuity (especially between the latch and fuse block). Check for continuity while manipulating the wiring by hand. I think you will find an internally broken wire or two somewhere.