Vehicles with a semi automatic transmission allow you to change gears manually, or let the computer do it for you. They are designed exactly like a manual transmission, and a little device called a clutch actuator allows the ECU to command the clutch on and off. A P0902 DTC means that there is a low voltage situation with the clutch actuator.
How Serious is the Code?
Since the transmission computer cannot control the operation of the clutch, the P0902 diagnostic trouble code is quite serious.
Symptoms of a P0902 include:
- Engine refuses to start
- Engine stalls when coming to a stop
- Transmission stays in a single forward gear
- Limp Mode
- Clutch actuator has failed
- Failing solenoid
- Failing clutch stroke/movement sensors
- Damaged wiring and/or connectors
- Ground for the control module has come loose
- Failed fuse or fusible link
- Failing clutch master cylinder
- ECU programming issues
- Faulty ECU or TCM
How to Diagnose the Code?
In order to properly diagnose a P0902 OBDII trouble code, a technician will have to familiarize themselves with the proper repair diagnostic procedures for your particular type of vehicle. But generally speaking, the diagnostic process will include checking the wiring, connectors, clutch actuator assembly, clutch master cylinder and any associated control modules and solenoids.
What Repairs Will Fix P0902?
- 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
- P0901 – Clutch Actuator Circuit Range/Performance
- P0903 – Clutch Actuator Circuit High