Ignition failure sensor is used to check whether the spark ignition is occurred correctly or not and also used to tachometer drive. The sensor monitors the voltage difference between a resistance which is on the battery circuit for ignition coil. When the ignition coil works properly, the electric current through the resistance is detected as voltage drop. This is confirmed for every ignition event with the crankshaft sensor and the camshaft sensor. If ECM detects sensor’s malfunction, no ignition is possible, so the engine would not start. If there is no ignition signal for predetermined cycle for one or two ignition coils, it is regarded as the ignition coil failure.
If there is no current at the 3 ignition coil group, the ECM judged as a fault and DTC is set.
Item
Detecting Condition
Possible Cause
DTC Strategy
? Current through ignition coil is monitored
? Poor connection
? Open or short in Tachometer circuit
? Defective ECM
Enable Conditions
? Engine speed < 4000rpm
Threshold value
? No current at the 3 ignition coil group(during 32 ignitions)
Diagnostic Time
? Continuous
MIL ON condition
? 1 driving cycle