How to Test 4Matic Diagnostics


1. Locate the OBD (onboard diagnostics) port in your Mercedes by referencing the owner's manual. Typically, the ODB port is located underneath the steering wheel.
2. Insert the plug coming from your code reader tool into the OBD port, then turn your Mercedes' ignition to the 'Accessories' position so that the stereo and associated electronics are activated.
3. Allow the code scanner to automatically scan for any codes that will be outputted once the car's electronics system is activated.
4. Take note of the codes that are displayed on the screen of your code reader as you will need to reference this list.
5. Contact your Mercedes Benz dealer or an authorized mechanic and request a translation of the error codes. Alternatively, many auto parts stores carry books in-house that will allow you to determine what the codes mean and which parts of your 4Matic system are failing.