P2797: Electric/Auxiliary Transmission Fluid Pump A Performance/Stuck Off

P2797 says pump A was asked to deliver but no useful pressure resulted. GM checks this on CVTs during an engine auto-start: with the pump commanded and over 400 kPa requested at both pulleys, both pressure sensors reading under 200 kPa for more than 0.525 s set the Type B code. GM bulletin 19-NA-200 (Malibu 2019–2025, Trailblazer, Encore GX, 2025 Equinox) blames an internal pump failure and replaces pump and harness. Subaru found false detections on 2023–2024 Legacy and Outback 2.4 turbo CVTs, caused by forward clutch engagement at restart, and released TCM files (16-145-23R). Stellantis traces P2797 on some 2026 Charger, Grand Cherokee and Wagoneer models with the 880RE eight-speed to a failed oil pump motor (21-053-26). Stop-start is usually the first casualty.

Medium severity. Can I keep driving?Drive gently to a repair shop. If it slips, you hear clunks, or it loses its gears, do not keep driving.

Symptoms

MIL on
Stop-start inoperative
Shock or surge when the engine restarts at a stop
Service transmission message

Most likely causes

Internal failure of the auxiliary pump or its motor
Control software misjudging pump output (TCM update available)
Damaged pump wiring harness
Low fluid or internal leakage preventing pressure build-up

What to check, in order

Start with the simplest. You can tick off each step.

Check the fluid level and condition
Compare the reading with other engine data while varying the engine speed.
Read the input and output speed in live data
Check the connector and wiring
Check for other related engine codes
Consult the manufacturer's procedure for the transmission

Good to know

It can trigger limp mode.
It affects emissions.

What each character of P2797 means

P: Powertrain: engine and transmission
2: Generic code: same on every make
7: Transmission
97: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2797?

Drive gently to a repair shop. If it slips, you hear clunks, or it loses its gears, do not keep driving.

What causes code P2797?

The most common causes are: internal failure of the auxiliary pump or its motor; control software misjudging pump output (TCM update available); damaged pump wiring harness.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.