For 1990-2009 cars

### Results of Incorrect Operation

1. An open or ground in the IC or bypass circuit will set DTC P1350 or P1361. If a fault occurs in the IC output circuit when the engine is running, the engine may falter or quit running but will restart and run in the module mode once the ignition has been cycled. A fault in either circuit will force the ignition system to operate on the module mode timing (10° BTDC), which will result in reduced performance and fuel economy.

The PCM uses information from the engine coolant temperature sensor in addition to RPM to calculate the main spark advance values as follows:

• | High RPM = more advance

• | Cold engine = more advance

• | Low RPM = less advance

• | Hot engine = less advance

2. Therefore, detonation could be caused by high resistance in the engine coolant temperature sensor circuit. Poor performance could be caused by low resistance in the engine coolant temperature sensor circuit.