Rear tailgate does not go up or down. I can hear the pump running when I activate from the rear handle or hit the down button. The hatch will unlatch and latch when I raise or lower the tailgate manually and the pump has the correct level of fluid in it. My thought is that the pump would not run if the sensors were bad, that plus the fact that the odds of the up and down sensors going out at the same time doesn't seem very likely. I'm leaning towards the pump just being worn out and no longer can generate the pumping psi to work the tailgate but I'd still like to get some other thoughts before I start playing "parts roulette". Thanks guys, Will

 

Does it work manually?

 

How did you check the level of hydraulic fluid? You have to remove the pump and hold it vertically to get the correct reading. Mine was low by only a very small amount. Topped it up and runs perfect.

It used to make a horrible whine sound when it tried to move. No idea it was such a simple fix.

 

😁

 

The fluid level is right on the money, held it vertically and it's right up to the line. I'm stumped as to why it's not lifting or lowering the tailgate unless the viscocity of the fluid I used is radically thinner than the mercedes stuff.

 

hello,

I had the same issue with my 2008 x164. I posted the fix.. read it and order the 2 sensors that go on the left/right side of the trunk.. once I replaced these sensors my tailgate worked fine.

https://mbworld.org/forums/gl-class-...ml#post8818723

 

I think the difference is that my motor does make noise when activated with the latch or remote. It sounds like your motor wasn't allowed to activate from the bad sensors. Correct me if I'm wrong because I would to just have the bad sensors. Thanks. Will

 

no, same problem as you. So after I replaced my pump it made noises just didn’t go up/down. I am pretty sure your sensors need to be replaced. The sensors are $35.00 each and very simple to remove. Buy the sensors and install them and report back. You won’t be disappointed as they are known part to fail over time. I followed this below to remove them




QUOTE=audioneurotica;8822314]I think the difference is that my motor does make noise when activated with the latch or remote. It sounds like your motor wasn't allowed to activate from the bad sensors. Correct me if I'm wrong because I would to just have the bad sensors. Thanks. Will[/QUOTE]

 

[/QUOTE]
Apologies, I didn't see the part of your post where you state the motor making noise but not moving the tailgate. Your advice did not fall on empty ears, next step is to order the sensors and cross my fingers. Thanks, Will

 

Remember, it is not a difficult fix to convert the power tailgate to manual. At least that's what FCP Euro says:

GL Manual Tailgate Conversion (W164 and X164)

 

My liftgate does not move up or down- no sound at all. I disconnected the leads to the pump and used a 12 v drycell battery to see if the motor/pump would run. The motor did run, so I know it is not getting power, presumably because of a rear SAM malfunction, faulty obstruction strips, or faulty liftgate module. am leaning toward the liftgate module as the problem, because the gate will neither open nor close and because I installed a used rear SAM and had it re-initialized due to other electrical issues. The shop that re-initialized the SAM told me that everything the SAM controls is working and that the tailgate issue is a bad motor/pump. Does anyone know of a method to troubleshoot the liftgate module? Any advice will be appreciated.
I am new to this site, and may not have posted this correctly, so please forgive the newbie.