P2796Electric/Auxiliary Transmission Fluid Pump A 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
- P2796 points to an interrupted control line between the module and the motor of auxiliary pump A. GM's 2025 TCM tables define the test: provided the battery supplies 9 to 15 V, the controller sees more than 200 kΩ from signal to ground in at least 20 of 25 samples taken every 100 ms; the code is Type B, so the MIL comes on after two trips. On Ford's 10R60/10R80 and 8F57 automatics the pump itself reports that the PWM command signal is missing, filed as P2796_31. Ford TSB 26-2010 covers the 2022–2025 F-150 Lightning, where P2796 or P2797 in the secondary OBD modules B and C may stem from software, often first logged at 0 °C or below; reprogramming is the fix. P2798 and P2799 are the short-circuit siblings, P27A2 the same fault on pump B.
- What you may notice
- MIL or wrench indicator on
- Stop-start inoperative
- Reduced performance message on electrified models
- Likely causes
- LikelyBroken control wire or unplugged pump connector
- PossiblePoor terminal contact at the pump or module
- PossibleModule software (Ford F-150 Lightning, TSB 26-2010)
- RareOpen circuit inside the pump electronics
- 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: €0 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.