Fault Diagnosis, General

NOTE: After conducting an operational test, always erase the fault memory with the command "CLEAR FAULT CODES". All systems can be erased with the command "CLEAR".

1. SDA MkII, which is an adapter, should always be connected to the ISAT scan tool.

2. The data link connector, which is green, is located under the right-hand front seat. The connector is covered by the trim which is slitted and is held in place with clips.

3. The ignition should always be on during fault diagnosis.

4. Read and note diagnostic trouble codes stored in all systems before the battery and the control module are disconnected.

5. If no communication can be achieved between the ISAT scan tool and the control module, first check that the fuses are intact and that there is supply voltage to the fuses. Then check the leads between the control module and the data link connector.

6. Also check that voltage supply and ground are correct in the data link connector, and that the connector pins are undamaged and not loose.

7. To avoid damage to the control module/components, always check that the ignition in switched oft before connector(s) are unplugged.


8. Check that control module grounding connections and supply voltages are correct.


9. It is sometimes useful to unplug connectors and check that connections and pins are undamaged and not loose. Reconnect all connectors and erase all diagnostic trouble codes. If possible, start/drive the car and check if the fault(s) remain.

10. All voltages around the 12 volt level are proportional to battery positive voltage and, for this reason, the levels should only be used as a guide.

11. 0 volt signals designate ground or 0 volt level. On a sensitive multimeter, a grounding point may give measurable voltage and a 0 volt level (output signal) can, without there being a fault, be around I volt. For this reason, voltage level should only be used as a guide.

12. Never switch from one unit to another (for example from volts, via amps to ohms) on the meter, without first having unplugged the instrument test leads.