Before Control Module Replacement

When all tests have been carried out as described in the diagnostic procedure under the relevant diagnostic trouble code, or by manual fault diagnosis, without any faults having been detected, it is natural to assume that the control module is at fault.
For this reason, check through the following points very carefully before definitely settling on the anti- theft alarm's electronic control module as the cause of the fault.

1 Check once again that all the points in the fault diagnosis schedule for the relevant diagnostic trouble code or fault symptom have been covered.
2 Study the wiring diagram of the circuit in question and make sure that you understand it. If necessary, refer to appropriate pants of the technical description and the electrical descriptions of operation in Service Manual 3:2 "Wiring diagrams".
3 Check all grounding points. If you have already done so, do it once again. Check that power ground and sensors are mechanically and electrically isolated from each other.
4 Check the control module's power supply.
5 Experience from M93 shows that most of the control modules returned for warranty repairs were not faulty.
Be restrictive with control module replacement. Unnecessary replacement of control modules constitutes a major expense for Saab Automobile and Saab dealers. Give careful thought to possible causes of the fault before changing the control module.
6 If the original fault persists in spite of this, then the anti-theft alarm control module will have to be changed.