Main code 22 indicates a fault within a speed sensor, the wiring to a speed sensor, incorrect speed sensor gap, or damaged bumps or teeth which create the speed signal. This fault is determined by the reasonableness of a speed sensor signal when compared with the other two speed sensors and the commanded range. A speed sensor will not pass the reasonableness test if there is no signal at all from that sensor when a signal should be present.
Allison WTEC II Fault Code: 22 PID: SPN: 14 FMI: Engine speed sensor reasonableness test
Allison WTEC II Fault Code: 21 PID: SPN: 23 FMI: Throttle position sensor, failed high
Allison WTEC II Fault Code : 21 PID: SPN: 12 FMI: Throttle position sensor, failed low
Allison WTEC II Fault Code: 14 PID: SPN: 23 FMI: Oil level sensor, failed high (not used)
Allison WTEC II Fault Code: 14 PID: SPN: 12 FMI: Oil level sensor, failed low
Allison WTEC II Fault Code: 13 PID: SPN: 23 FMI: ECU input voltage, high
