Door Switches In Central Locking System

Fault symptom
The central locking system does not work. The alarm cannot be disarmed by means of the front door key locks.







Diagnostic procedure
1 Check the operation of the central locking system
- Connect an Intelligent Saab Tester (ISAT) scan tool.
- Select "READ VALUES".
- Select "LOCK SIGNAL" or "UNLOCK SIGNAL".
- Lock or unlock the central locking system using the door key lock.
The ISAT scan tool should display "INACTIVE" when the key is in its normal position and "ACTIVE" when the key is turned.
Does it display correct readings for the locked and unlocked central locking system?
[YES] Continue with point 2.
[NO] Continue fault diagnosis as described in - Service Manual 3:2 "Electrical system "Central locking".







2 Check the programming
- Select PROGRAMMING".
- Select "LOCK DEACTIVATION".
- Check the programming of the electronic control module. See the "PROGRAMMING". Command Menus
Is "OFF" programmed?
[YES] Change it to "ON".
[NO] If "ON" is programmed, continue with point 3.

3 Check the operation of the central locking system
- Select "READ VALUES".
- Select "UNLOCK SIGNAL".
The ISAT scan tool should display "INACTIVE" when the key is in its normal position and "ACTIVE" when the key is turned.
Does it display correct readings?
[Yes] Proceed to point 5.
[NO] Continue with point 4.







4 Check the wiring
Check the wiring harness for continuity between:
- the electronic control module (pin 17) and the central locking system (pin 5)
- the electronic control module (pin 6) and the central locking system (pin 6)
The resistance should be < 1 ohm.
Is the resistance OK?
[YES] Continue with point 5.
[NO] Repair or replace the wiring harness.

5 Final test
Check to see if the fault symptom persists.
Does the trouble persist?
[YES] Continue as described in "Before Changing The Electronic Control Module".
[NO] The remedial measures taken were correct or the fault is of intermittent nature.