Checking the Power Supply and Grounding

Fault symptom
Anti-theft alarm completely unserviceable. No communication with the Intelligent Saab Tester (ISAT).

Diagnostic procedure
Power supply
1 Check that fuse 23 is intact and live with current.
2 Connect the BOB and check whether voltage is present across pin 13 of the control module connector and a good grounding point.
The voltage should be about 12 V.
If the voltage is OK, proceed to point 4.
3 Check the wiring for continuity/shorting by measuring the resistance across the output side of the fuse and pin 13 of the control module connector.
The resistance should be < 1 ohm.





Grounding
4 Check the grounding of the anti-theft alarm by measuring the resistance across pin 10 of the control module connector and a good grounding point.
The resistance should be < 1 ohm.
If the resistance is OK, proceed to point 6.
5 Check that there is zero voltage (0 V) on pin 10 of the control module (control module disconnected) by measuring across pin 10 of the control module and a good grounding point.
6 If the fault persists after the above checks have been carried out continue fault diagnosis as described in "Before Control Module Replacement".