P073EUnable to Engage Reverse
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P073E means reverse is commanded but not reached. Two uses are documented. With electronic gear selection (shift-by-wire) GM compares the commanded range with the actual range reported by the transmission and flags it if reverse is not reached within 1.8–3 s in the selector or diesel engine module, or 10 s in petrol engine modules, after two trips; GM bulletins name a range actuator centred wrongly (LaCrosse, XT5) and software after an over-the-air update (2025 Equinox/Terrain). On dual-clutch transmissions (2020–23 Corvette, Maserati MC20) it means the reverse gear cannot be engaged. Stuck in reverse is P072B, slip in reverse P0736.
- What you may notice
- No reverse, or R not accepted
- Transmission warning, check engine light after two trips (GM)
- Display shows R but the vehicle does not reverse
- Likely causes
- LikelyRange actuator or park module centred wrongly or faulty (shift-by-wire)
- PossibleModule software (e.g. after an over-the-air update)
- PossibleRange sensor reports the wrong actual range
- PossibleReverse clutch or brake, valve or shift fork (DCT)
- RareFluid level or system pressure
- 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: €50 – €5,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.