If a Vauxhall Ampera owner is experiencing unexplained discharge of the 12V battery or unexpected triggering of the car’s alarm, it may be related to a problem with the keyless central locking system.
Because of water ingress and corrosion affecting the door handle switches, the receiver detects an opening request and sends this signal to the body control unit.
At the same time, the vehicle’s interior lighting is switched on and the vehicle electronics are ‘woken up’, which can lead to unwanted current consumption and ultimately to the discharge of the 12V battery serving the vehicle electrical system.
If, as part of the fault diagnostics procedure, no defects in the charging system or on the 12V battery show up, the central locking system should be checked out.
Using a diagnostic device, read out the parameters in the body control unit and then put water on the door handles in turns. If this alternating action changes the parameters on a door handle or even switches on the interior lighting, then the cause has been localised.
In such a case, the relevant door handle with its integrated switch is to be replaced.
This defect may also occur in other models with the same type of central locking system. Remember to follow the repair instructions from the vehicle manufacturer when carrying out this repair.