My 08 ML350 front passenger door lock no longer works with the fob or lock/unlock button. It has to be manually locked and unlocked. Has anyone found a fix for this? Trying to avoid going to MB dealer. Thanks, all!

Do you have a scanner? Codes will help with diagnostics. I have a GL with a similar problem. I can't lock or unlock using the button or handle, but the fob locks and unlocks it. What about using any of the other doors? Can you lock or unlock it that way? I have Keyless Go, as reference so I only have to touch the handle to unlock. Do you have Keyless Go as well or no?

Yes I have a scanner. All other doors work properly, but the passenger door has to be locked/unlocked manually. I do not have keyless go.

Well, did you check for code/s in the Door section?

Check the various repair kits on Ebay.
The springs gets weak and you can replace the spring in the actuator.

" For 06-11 Mercedes M-Class ML Door Lock Actuator Repair Kit W164 4 Springs US"
On ebay and you tube.
It is a bit of work or buy try another lock actuator.
Check the parts catalog both lkefts and both rights are the same part number.

The plastic door switch button broke. Bought a new after market botton, swapped the plastic
button with nibs intact. 30 second repair.
Driving a 10 year car is an adventure.