P27A3 code meaning
Electric/Auxiliary Transmission Fluid Pump B Performance/Stuck Off
Powertrain system Generic code P27xx codes Check engine light
What P27A3 means
P27A3 means auxiliary pump B was commanded but did not deliver: no pressure build-up, too little speed or a motor that does not respond at all. Audi documents the code. Its bulletin 34-17-25, revision 3 from 2017, covers model year 2017 A4, A5, A6 and the 2018 Q5 with the 0CJ, 0CK and 0CL seven-speed twin-clutch boxes and names P27A300, next to P27A6, P276B and U28A0, as possible companions of a rattling gear oil pump V553; a supplier assembly defect was the cause, and the pump is renewed with new bolts. For pump A the matching code is P2797, which GM's 2025 CVT tables set when both pulley pressures stay below 200 kPa during an engine auto-start. Mechanical seizure, low fluid or a weak motor are typical; stop-start goes offline.
P27A3 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.5 to 5 hours
- Clears after repairAfter a drive cycle
Symptoms of P27A3
- Rattle from below the car near the gearbox
- Stop-start disabled
- Delayed or harsh engagement after an engine restart
Common causes of P27A3
- Most likelyPump B mechanically defective or seized (e.g. assembly fault on Audi V553)
- PossibleFluid level too low, pump draws air
- PossibleWorn pump motor or high resistance in its supply
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Aux trans pump bPump motor
What each part of P27A3 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. |
| A3 | The exact fault in that area. |
What to do next
- Note P27A3 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 P27A3
What does P27A3 mean?
P27A3 means "Electric/Auxiliary Transmission Fluid Pump B Performance/Stuck Off". P27A3 means auxiliary pump B was commanded but did not deliver: no pressure build-up, too little speed or a motor that does not respond at all. It is a generic code, so it means the same on every make.
Is it safe to drive with P27A3?
Drive gently and only to a workshop. With P27A3 the car can go into limp mode (reduced power) to protect itself.
Will P27A3 fail an emissions test?
Yes, it can. P27A3 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 P27A3 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 5 hours of work. This is a job for a workshop.
Will P27A3 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.