P0C2A: Electric/Auxiliary Transmission Fluid Pump A Motor Stalled
What to do
If this appeared on a very cold morning and the car has been fine since, say so — thick fluid can stall this pump without anything being wrong with it, and that is a much better outcome than the alternative. Otherwise the likely causes are physical: debris or a seizing pump. Fluid condition is the cheap thing to check first, and a pump replaced into dirty fluid tends to stall again.
What this code means
The auxiliary pump has been commanded to turn and has not turned.
This is the least ambiguous code in the family and the most actionable. Everything else in it describes a measurement being wrong; this describes a mechanical fact. The module knows the pump is stalled because it is drawing current and producing no rotation — the electrical side is working and the shaft is not moving.
That narrows it to a short list of physical causes. Debris is first, because this pump is small, its clearances are tight, and it draws from the same fluid as everything else in the gearbox — so wear particles reach it. A seizing bearing is second. And fluid too cold and thick to move is a genuine third that is not a fault at all: some designs will report a stall on a hard frost and run perfectly once warm, which is worth knowing before a pump is bought on the strength of one winter morning.
A stalled pump means no line pressure with the engine off, so the P0B00 symptoms arrive in full.
Likely causes
Start here
- Seized pump motor · specialist
- Debris in the transmission fluid · specialist
- Faulty auxiliary transmission fluid pump · specialist
Less common
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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