P27E4Electric/Auxiliary Transmission Fluid Pump Control Valve Circuit Range/Performance
- 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
- P27E4 is the plausibility check for the auxiliary pump control valve: the circuit is intact, but its current or its hydraulic effect does not match the command. No manufacturer lists the code publicly, so the logic can only be inferred. In a layout like Volkswagen's 0GC dual-clutch box, where a pressure regulator moves a changeover piston to steer the oil of the electric pump, a sticking piston or a coil with drifting resistance would cause exactly this mismatch. CARB 13 CCR 1968.2 asks for both electrical and functional monitoring of transmission actuators. Dirty fluid and varnish are the usual reasons a valve hangs. Unlike P27E3, P27E5 or P27E6 the wiring tests pass here; P27E1 may follow if pressure stays too low.
- What you may notice
- Stop-start works only sometimes
- Harsh engagement after an auto-start
- Warning light on
- Likely causes
- LikelyValve or changeover piston sticking from contaminated fluid
- PossibleCoil resistance drifting with temperature
- RareContact resistance at the connector distorting the current
- 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: €150 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.