1998 300 E Turbo D Mercedes Benz Driver Door will not lock

If the dealer had change the part you sayd ask them to reset the ECU or the main computer off or car it should solve the problem

Radio removal is not likely the cause.Check fuses, especially for alarm and door locks. Make sure door locks work (door locks and alarm are controlled by the same part). Make sure your battery isn't weak. Does the key turn? does the starter engage?

Push the unlock button on the drivers door. It should unlock all the doors in the car.

You must turn the car on after alarm goes off. Door locking and unlocking dont work after the alarm goes off. Its like you break a window to get in anyone can lock or unlock a door thats why its tied to the ignition.

From what you describe, it sounds like someone tried to slim-jim the door lock and dislocated the metal rod from the lock cylinder mechanism. There are two rods; one to the lock mechanism, and the other to the interior pop-up lock shaft. If the interior lock shaft is going up and down, but the door is not locking and unlocking, the rod to the lock cylinder/mechanism has fallen off (this is very common when someone tries to slim-jim the door for entry). To repair requires the interior door panel to be removed and the rod to be reinserted back into the small L-shaped plastic clip.

there is a sensor in the drivers door that senses the door is locked or unlocked, if the sensor is defective the alarm will sound.

try to remove the door panel,might be the micro switch for alarm is stock,or some linkage maybe disconnected to the swich.

you need to insert the key into the drivers door lock it then unlock it

if that don't work, do the same with the passanger door
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which means the switch to the drivers door is bad

Use your door key and unlock your drivers door ... that is what disables the alarm system. Make sure that the battery is rehooked... because i'm sure you took the battery loose when you couldn't get the alarm to turn off.