P094BHydraulic Pump Stuck On
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- The hydraulic pump keeps running although the module has switched it off, or it never reaches its cut-out point. Causes are a welded relay or shorted driver, or a pump that cannot reach cut-out pressure because of leakage. No manufacturer documents this exact code publicly. In the pump and accumulator unit of an automated gearbox, described in a ZF patent, the pump should rest once the accumulator is charged. Toyota links a constantly buzzing pump on the MR2 sequential gearbox to fluid loss at the hydraulic power unit, reported under P0942. CARB requires functional checks on outputs. P094C is the opposite fault, P0946 the relay plausibility fault, P0943 the too-short cycle. Battery drain and pump wear follow.
- What you may notice
- Pump audible after the vehicle is switched off
- Discharged battery
- Warning light on
- Likely causes
- LikelyPump relay contacts welded closed
- PossibleLeakage or lost accumulator charge keeps pressure below cut-out
- PossibleShorted driver stage or supply wire shorted to battery voltage
- 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: €30 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.