Possible causes – Faulty Vacuum Pump Module– Vacuum Pump Module harness is open or shorted– Vacuum Pump Module circuit poor electrical connection.– Faulty Engine Control Module (ECM) When is the code detected? To determine leak criterion (Reference pressure), vacuum pump
Possible causes – Faulty Vacuum Pump Module– Vacuum Pump Module harness is open or shorted– Vacuum Pump Module circuit poor electrical connection.– Faulty Engine Control Module (ECM) Tech notes There is a factory service bulletin for the following Toyota models:
Possible causes – Faulty Vacuum Pump Module– Vacuum Pump Module harness is open or shorted– Vacuum Pump Module circuit poor electrical connection.– Faulty Engine Control Module (ECM) When is the code detected? To determine leak criterion (Reference pressure), vacuum pump
P2401 Information for specific makes P2401 DODGEP2401 LEXUSP2401 TOYOTAP2401 SCION
P2401 DODGE – Cylinder #9 Above Knock Threshold