P27E4 code meaning
Electric/Auxiliary Transmission Fluid Pump Control Valve Circuit Range/Performance
Powertrain system Generic code P27xx codes Check engine light
What P27E4 means
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.
P27E4 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 5 hours
- Clears after repairAfter a drive cycle
Symptoms of P27E4
- Stop-start works only sometimes
- Harsh engagement after an auto-start
- Warning light on
Common causes of P27E4
- Most likelyValve or changeover piston sticking from contaminated fluid
- PossibleCoil resistance drifting with temperature
- Less likelyContact resistance at the connector distorting the current
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Aux transmission pump control valveWiring harnessTCM
What each part of P27E4 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 7 | Area: transmission. |
| E4 | The exact fault in that area. |
What to do next
- Note P27E4 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P27E4
What does P27E4 mean?
P27E4 means "Electric/Auxiliary Transmission Fluid Pump Control Valve Circuit Range/Performance". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with P27E4?
Drive gently and only to a workshop. With P27E4 the car can go into limp mode (reduced power) to protect itself.
Will P27E4 fail an emissions test?
Yes, it can. P27E4 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P27E4 to fix?
Difficulty: hard. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P27E4 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.