Here is the instruction show you guide on how to solve Scania truck Micro switch door lock driver's side (truck)/micro switch A1 (bus), short circuit.
What you need?
Scania SDP3 2.69.3 Truck diagnostic software
Error identification
The micro switch is short-circuited to the voltage supply.
Cause
Fault in harness-to-component connector or cable harness to the micro switch.
Fault in the micro switch.
Fault in ALM control unit E7.
If the alarm system is activated when the fault code is generated the siren will sound.
Symptom
The micro switch is out of order.
Action
1 Disconnect the micro switch. Note whether a new fault code for a broken circuit has been generated. If this is the case, the fault is probably in the micro switch.
2 Measure the pins in the nearest harness-to-component connector going to control unit pin B1.
3 Disconnect the harness-to-component connector on the control unit.
4 Measure for short circuits throughout the cable harness.
5 If there are a number of harness-to-component connectors between the micro switch and the control unit, then also measure these to locate the fault.
6 If the fault is not in the cable harness or the micro switch, it is probably an internal fault in the control unit.
