Ignition Control Module: Description and Operation

The ECU is fitted to a bracket on the floor underneath the lefthand front seat. It houses a microprocessor and an EPROM chip containing basic ignition timing parameters. The ECU has been programmed with data on all conceivable driving conditions and is therefore able to optimize the timing at any given instant. If a fault should occur in the microprocessor, the spark will be triggered direct from the crankshaft sensor.
The ECU incorporates a self-diagnosis function, which continually monitors the operation of the system both on starting and when the engine is running. Any faults detected are stored in memory and can be accessed using an ISAT tester.
The ECU is a sealed unit and cannot be modified in any way. If the ECU is defective, the unit must be replaced.