Problem with W166 ML250 powered tailgate

[Merc Owner 2B]

If the tailgate hasn't been used for a day or so when I open it (key or doormounted switch) it unlatches and just sits there, doesn't raise.
I then lift it by hand (bit of resistance from motor) to its full open point and press the tailgate mounted button and it closes normally. From that point it works fine until rested for a day an dthen it fails again.

It's as if leaving it for a day interfers with the sensors switches??

I'm waiting for it to completely fail as sods law says it will work if I take it in the dealership!

Anyone had similar experiences?

 

[jaymanek]

So its under warranty? Take it back... Either it needs re teaching its limits or the motor is failing.

 

[Merc Owner 2B]

Hi Jay

Yes, it's under warranty but never plays up when the dealer has it! Nothing shows on STAR. They think it might be the latch not telling the SAM that it's undone or the SAM faulty or the motor failing.
Just wondered if anyone else had had problems. Waiting for it to fail completely now!

 

[jaymanek]

Id push for a new mechanism...

 

[Merc Owner 2B]

An update just to complete this thread for any interested parties.

Took the car in for its first service and asked them to check the tailgate.

Apparently fault codes were logged indicating that the tailgate motor position sensors are at fault.

New motor being fitted next week. £601 paid for by warranty.

Hopefully should resolve the problem. If not will report back.

 

[Merc Owner 2B]

Just to add that the fault hasn't returned.