Originally Posted by Scotto97

My 2 key fobs stopped working at the same time (Not locking or unlocking remotely, nor are the lights flashing when buttons are pressed)
When I tried using the key manually, only the driver's side door locks (The air pump is not receiving a signal to lock the passenger door, glove box, or trunk)
However, when I unlock the driver's door manually, it does unlock the passenger door using the air pump.
Also, all doors lock and unlock correctly when using the interior button.
I've switched out air pump modules with the same result, so it isn't the pump.
Is it possible the defective driver's lock actuator is confusing the system (Not knowing what is locked and unlocked) and therefor has turned off the ability for the fobs to work?
Rob at Needswings believes it's still SCREEM related, but Mercedes Swap Shop is not convinced it is a SCREEM issue.

Thoughts? Should I replace the roughly $160 actuator first before spending $700 + on the SCREEM repair?
Could the security siren be involved somehow in stopping both keys from responding ?