Diagnosis instructions

Note the following information for diagnoses on the Car Access Systems:

Checking the remote key 

The remote key can be checked using the diagnosis system. If the remote key is inoperative, proceed as follows:

• First check whether another remote key belonging to the same vehicle works
• Check the remote key battery charge
• Measure the electrical field strength

The electrical field strength of the remote key can be measured using the diagnosis system and the control unit functions of the CAS. A button on the remote key must be pressed to take the measurement. If a value for the field strength is read out, this means that:

• the transmission distance between the remote key and the remote control receiver is OK, no sources of interference detected.
• the signal line from the remote control receiver to the Car Access System (CAS) is OK.

As the remote key moves further away from the vehicle, the measured field strength drops.