On vehicles equipped with a semiautomatic transmission, gear changes take place when the TCM actuates the clutch actuator to engage or disengage the clutch. If there is a performance issue with the transmission clutch actuator, a P0901 DTC will be saved.
How Serious is the Code?
A P0901 diagnostic trouble code means that the the TCM is not able to properly control the clutch, which can lead to a number of transmission problems that include engine stalling and a failure to shift gears.
Symptoms of a P0901 include:
- Engine will not start
- Engine stalls
- Transmission is stuck in a single gear
- Limp Mode
- Faulty clutch actuator
- Faulty solenoid
- Faulty clutch stroke/movement sensors
- Damaged wiring and/or connectors
- Loose control module ground
- Faulty fuse or fusible link
- Faulty clutch master cylinder
- ECU programming issues
- Faulty ECU or TCM
How to Diagnose the Code?
Because each manufacturer’ transmission designs vary greatly, the diagnostic procedure for a P0901 OBDII trouble code can be just as different. For example, low brake fluid can actually cause a P0901 OBD2 code, so it’s important to consult the diagnostic procedures outlined by the manufacturer.
What Repairs Will Fix P0901?
- Replace transmission clutch actuator
- Replace solenoid(s)
- Replace sensor(s)
- Repair or replace wiring/connectors
- Replace failed fuses and/or fusible link
- Replace clutch master cylinder
- Update ECU programming
- Replace failed TCM/ECU
- P0900 – Clutch Actuator Circuit/Open
- P0902 – Clutch Actuator Circuit Low
- P0903 – Clutch Actuator Circuit High