P2712Hydraulic Power Unit Leakage
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2712 targets gearboxes whose clutches or shift forks are worked by a separate hydraulic power unit, typically an electric pump that charges a pressure accumulator. Such a system loses pressure only slowly when sealed; if pressure drops faster than expected or the pump has to recharge too often, the controller concludes there is a leak. No manufacturer documents P2712 publicly. The principle is described in Volkswagen's training booklet for the dry seven-speed DSG 0AM: an electric pump fills a 0.2 l gas accumulator, switches off at about 60 bar according to the pressure sensor and restarts near 40 bar. CARB counts automatic transmission controls among the monitored output components. A leaking accumulator, valve or seal can end in lost gears; P0944 covers a general pressure loss of the hydraulic unit.
- What you may notice
- Hydraulic pump running often or for long periods
- Gears not engaging or delayed engagement
- Gearbox warning and emergency mode
- Likely causes
- LikelyLeaking or worn pressure accumulator
- PossibleInternal leakage at valves or seals of the hydraulic unit
- PossibleExternal oil leak at housing, lines or connector seals
- RareImplausible pressure sensor signal
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €400 – €4,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.