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Mercedes-Benz key fob not working?
The first thing you need to do is change the keyless remote battery.
We assume you have already done that part by now.
Is your Mercedes key fob not working after a battery change?
This article will help you troubleshoot problems where the Mercedes key fob doesn’t work or no longer unlock/locks doors or trunk. In most cases, the key can start the car but not work as a keyless entry remote.
Generally speaking, when Mercedes key fob is not working, it’s because either because the key is defective or the All Activity Module (AAM) is not recognizing the key signal, or it is not receiving signal due to an antenna issue.
If you need a replacement battery note that Mercedes-Benz uses CR2025 battery type.
Is the Vehicle not opening or locking via the remote control ?
Is the Vehicle not Starting but opens and closes fine ?
Is the Vehicle Dash powered when inside the Vehicle ?
Is the Key turning but not starting and ignition does not come on ?
Is the key not turning and not able to get ignition on ?
If the Vehicle not opening or locking via the remote control then it can be a couple of things causing this and advise to check these first.
If the 2nd option allows start the car then the car battry is ok and the key needs to be replaced.
First try clean the first part of the key and ignition switch where the key goes inside as the IR signal from the key might be getting blocked.
if after cleaning the key does not turn then this could be faulty key or ignition switch
If the dash comes on then the battery inside the car is fine.
Try to open and close the doors using the central locking button in the car and can find out if the issue if with locking system or the key if it does not open or close.
This can happen when the motor inside the EIS is need of replacing.
First check is the Dashboard powered up when you insert the key ?
if it's not check car battery first and and try again and add jump leads or booster and recheck
The Eis needs power to be able to allow the key to turn in the ignition and if the dash is not lit up the chance if the battery in the car needing charging is most common issue.
Got a Mercedes A Class W176 that had new bi xenon headlamps fitted which replaced the standard halogen lamps.
Once fitted the front lights do not work and flicker continuously.
We managed to rewire the SAM and code the car to work with bixenom headlamps.
If you are interested please call the office to discuss.