General Fault Diagnosis Hints

1 The diagnostics socket is located under the dashboard beside the steering column.
2 Obtain readings of the diagnostic trouble codes for all systems and make a note of them before disconnecting the battery and any control modules.
3 If communication cannot be established between the Intelligent Saab Tester (ISAT) and the system, first check fuse 2 to find out whether current is passing through it.
4 Then check the leads between pin 2 of the anti-theft alarm control module connector and pin 8 of the diagnostic socket.
5 Also check that the diagnostics socket has power and the correct ground, and that the connector pins are undamaged and properly located.
6 Lists of all diagnostic trouble codes will be found in List of Fault Codes.
7 A list of all ISAT menus will be found in Command Menus.
8 To avoid damage to the control module and/or components, always make sure that the ignition is switched off before unplugging the connector.
9 Always check that the control module's ground connections and supply voltages are correct.
10 It may sometimes be worthwhile unplugging connectors to check that their sockets and pins are undamaged and properly located.
Plug in the connectors again and clear all diagnostic trouble codes. It possible, activate the alarm and check whether the fault or faults persist.
11 Since all signals round the 12-volts level are proportional to battery voltage. these levels should be used only as guidance.
12 zero-voltage (0 V) signals indicate ground but with a sensitive multimeter they can give a measurable voltage reading.
13 Never switch from one unit of measurement to another (e.g. from V via I to ohms) without first disconnecting the instrument's test leads.


Important: After completing fault diagnosis, always clear the fault memory with the "CLEAR FAULT CODES command.