The lock not working is a common problem on the central locking system cars.
Generally, it is the vacume activator in the door (or a line leading to it).
You'll find these easily (and reasonably available) and there are rebuild kits too.
The hardest thing is taking off the door panel...not really hard, but patience needed to not do damage.
Of course, the above is a common cause, yours may be something else.
The 2002 Mercedes-Benz E320 fuse box is located in the engine compartment. The fuse box will be on the drivers side of the engine compartment.
The cruise control on a 2002 Mercedes ML320 will stop working if the fuse has blown or the wiring has become loose. An OBDII code reader can be connected to the vehicle's computer to help diagnose the problem.
Read the drivers hand book or car manual. It is easy to do.
This is cluster failure! The instrument cluster will need to be replaced this is usually done by certified Mercedes repair facility
There is a tag in the drivers door that shows the correct tire size for the car you are working on
Where is the fuse box in the 2002 Mercedes Benz s430
where is the camshaft sensors located on Mercedes 2002 1800cc engine
The 2002 Mercedes-Benz G-Class has a V8 engine.
The 2002 Mercedes-Benz M-Class has a V6 engine.
The 2002 Mercedes-Benz SL-Class has 24 valves.
The 2002 Mercedes-Benz E-Class has a V6 engine.
The 2002 Mercedes-Benz S-Class has a V8 engine.