P0924Gear Shift Reverse Actuator Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Concerns the drive circuit that moves the shift mechanism of an automated manual gearbox in the reverse shift direction, i.e. opposite to the forward actuator. It does not mean the reverse gear itself. Depending on design this is the second solenoid valve of a double-acting shift cylinder or the second rotation direction of an electric shift motor. The code sets when the module finds this output open or electrically faulty. No manufacturer documents the code publicly. A ZF patent assigns one 3/2 solenoid valve to each cylinder chamber, an Isuzu patent reverses the shift motor depending on shift direction. CARB requires circuit checks on outputs. P0925 to P0927 are the siblings, P0920 the forward direction. Gears in this direction cannot be engaged.
- What you may notice
- Transmission warning light on
- Some gears cannot be selected or the gearbox stays in neutral
- Gear changes out of the current gear may fail
- Likely causes
- LikelyLoose, corroded or unplugged connector at the shift actuator or valve
- PossibleBroken drive wire between module and actuator
- PossibleOpen solenoid coil or motor winding in the actuator
- RareFaulty driver stage in the transmission control module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €2,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.