P2790Gate Select Direction Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2790 is the basic circuit fault for the signal that tells the controller in which direction the selector mechanism is moving across the gate, that is sideways between the shift lanes of the H pattern. In automated manual gearboxes the select actuator or its sensor provides this information; on some shift-by-wire levers it comes from the lever itself, so the exact part depends on the manufacturer. A circuit code means the signal is missing or of the wrong type, for example an open wire or a dead sensor, rather than a value that is merely too low or too high (those are P2791 and P2792). No manufacturer documents P2790 publicly; CARB 13 CCR 1968.2 requires circuit checks for such gearbox inputs. Results range from refused gear changes to a vehicle that stays in one gear or will not pull away.
- What you may notice
- Gear changes refused or gearbox stuck in one gear
- Vehicle may not move off from standstill
- Warning lamp with transmission message
- Likely causes
- LikelyOpen wire or loose, corroded connector at the select sensor
- PossibleFailed select direction sensor or select actuator electronics
- RareFault in the shift lever module where it supplies the signal
- RareDefective input stage in the transmission controller
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.