P27A2Electric/Auxiliary Transmission Fluid Pump B Control Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P27A2 flags a broken control circuit between the module and auxiliary pump B, the second electric fluid pump on gearboxes that carry two. While its output is energised, the controller compares the voltage on the line with the level an intact load would pull it to; a floating line reveals the interruption. No manufacturer documents P27A2 publicly. GM's 2025 TCM tables describe the identical test for pump A as P2796: more than 200 kΩ to ground in at least 20 of 25 samples taken every 100 ms, with 9 to 15 V supply, Type B. Audi ties its pump B codes to the gear oil pump V553 of the 0CJ, 0CK and 0CL twin-clutch units. P27A4 and P27A5 are the shorted variants. Typical faults are a cracked wire, a pushed-back pin or an open motor winding; stop-start is normally withdrawn.
- What you may notice
- Stop-start no longer active
- Transmission warning or MIL
- Harsh engagement when driving off after a restart
- Likely causes
- LikelyControl wire broken in the harness to pump B
- PossiblePump connector unplugged, pin pushed back or corroded
- PossibleOpen motor winding or internal connection in pump B
- 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: €50 – €1,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.