Mercedes Remote will not Lock or Unlock?

The doors will not get locked or unlocked by key-fob remote,but all work manually.

OK,in this case first try this :----

does the central locking switch on the dash lock the doors when you press it?

IF yes,then continue further:---


If the central locking switch on the dash works it tells you that the central locking pump is good. In that case I would have to suspect a fault remote or a fault with the remote central locking control unit. The fuses for the circuit should be checked first. They are fuse #23 and #27 in the main fuse box under the hood on the driver's side.


It would be a good idea to check all of the fuses in the front and rear fuse boxes as well. If all fuses are good and you get no response from the system when you point the remote at the mirror or at the door or trunk receiver I'd suspect a bad remote.


KEY FOB REPROGRAMMING PROCEDURE.

The theory says:--
When you insert the key into the ignition it reprograms itself each time. If the key is starting the car but not locking or unlocking the car you may need to replace the batteries in the key. If you have done that and it still will not operate the locks then the remote may be faulty. If you have a spare key that works fine it would rule out any other possible problems with the car.

This will help.
Thanks.

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Details regarding Remote controls?

Read this details before buying or getting your remote control repaired.

1. If you are buying a UNIVERSAL remote for some reason do not expect it to provide all the original functions or EVEN TO WORK FOR YOUR UNIT. You in most cases are better with the original---if the original does not work there are ways to deal with that.

A dead remote is usually bad batteries, dirty or loose connections or has had some liquid spilled into it.

Most remotes can be taken apart (if its dead nothing to lose here) and the circuit board cleaned with alcohol etc and the rubber like keypad washed with dish soap, dried completely and the unit usually works again.

2. NEVER STORE REMOTES WITH THE BATTERIES IN THEM FOR PROLONGED PERIODS OF TIME; the batteries can leak and a white mess similar to battery cables in a car occurs. This can be dealt with by cleaning all the white stuff out and cleaning the metal contacts by use of a small file or knife----DO NOT USE WATER etc for cleaning here.

3. Most shops have a remote tester, it is a card with a strip and when the remote is pointed at it the strip lights up (3 dollar item on the internet).

4. Lost remotes for many units are a problem----some never think to GOOGLE THE MODEL NUMBER OF THE SET with the word REMOTE after it---AVOID UNIVERSALS. Many units (TV combos, DVD, blue ray etc) MUST HAVE THE ORIGINAL REMOTE for all functions to be accessed.

5. Three things for the most part cause remotes not to work: DROPPED, LIQUID SPILLED, AND BATTERY ISSUES.

Dropped is most likely to be fatal if the board inside is damaged, the other two are fixable 95% of the time.

This details will help you to understand your remote control better.