Modern vehicles no longer rely on mechanical linkages to shift the transmission into gear. Instead they use a series of sensors to detect what gear you have selected, then the ECU will energize an electric motor to actually shift the transmission into the desired gear. A P0927 DTC means that they gearshift reverse actuator (which is responsible for shifting the transmission into reverse) is sending an unusually high-voltage signal back to the ECU.
How Serious is the Code?
When a vehicle has a P0927 diagnostic trouble code, it means that the transmission part responsible for shifting the transmission into reverse (gearshift reverse actuator), is not communicating with the ECU correctly. When this happens, you may not be able to shift into or out of reverse. And that can obviously impact the drivability of your vehicle.
Symptoms of a P0927 include:
- Transmission shifts erratically
- Transmission is not able to shift into or out of reverse
- Damaged wiring
- Corroded/broken connectors
- Broken gearshift reverse actuator
- Broken gear guide rail
- Broken shift shaft
- Internal mechanical problems
- ECU/TCM issues or failure
How to Diagnose the Code?
The process of diagnosing a P0927 OBDII trouble code should begin with a thorough inspection of all the wiring, connectors, fuses and relays on this circuit. The gearshift reverse actuator itself will also need to be tested. The gear guide rail and shift shaft should also be inspected for signs of damage and misalignment. If no problems have been found up to this point, then an internal mechanical diagnosis may be needed. The ECU and TCM may also be at fault.
What Repairs Will Fix P0927?
- Repair or replace any damage wiring or connectors
- Replace gearshift reverse actuator
- Repair or replace gear guide rail
- Repair or replace shift shaft
- Repair internal mechanical fault(s)
- Reprogram or replace ECU/TCM
- P0920 – Gear Shift Forward Actuator Circuit/Open
- P0921 – Gear Shift Forward Actuator Circuit Range/Performance
- P0922 – Gear Shift Forward Actuator Circuit Low
- P0923 – Gear Shift Forward Actuator Circuit High
- P0924 – Gear Shift Reverse Actuator Circuit/Open
- P0925 – Gear Shift Reverse Actuator Circuit Range/Performance
- P0926 – Gear Shift Reverse Actuator Circuit Low