Cause
Open circuit in pump wiring
The circuit feeding or controlling a pump is broken — a severed wire, a connector that has come apart, a corroded terminal that has finally stopped making, or a blown fuse.
The reason this cause deserves attention rather than a shrug is that a pump with no supply is indistinguishable from a failed pump. Both are silent, both deliver nothing, and both produce a code that names the pump. So the expensive part gets replaced to fix a broken wire, and where the pump is buried — in a tank, inside a transmission, under a battery pack — the labour costs more than the part. Checking that the pump is actually being fed is a few minutes' work and it comes first.
Pump wiring fails more than most for physical reasons. Pumps live in the places harnesses have the worst time: in wheel arches and under floors where salt and stones reach them, on or inside units that vibrate continuously, and often at the end of a long run where a small resistance has the most effect. Many are fed through a relay and a dedicated fuse, which adds two more joints that can fail and two more things that can be checked without tools.
Measure at the pump, not at the fuse box. A supply that is present at one end and absent at the other is exactly what an open circuit is, and a reading taken at the fuse proves only that the fuse is intact. Where the fault is intermittent, moving the harness while the circuit is watched will usually find the inch of wire responsible — which is worth far more than knowing the circuit is faulty.
Typically a moderate job.
Some of these codes mean you should stop driving
2 of the 31 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (31)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0230 Fuel Pump Primary Circuit Likely for this code Stop driving High
- P0A05 Motor Electronics Coolant Pump A Control Circuit/Open Likely for this code High
- P0A07 Motor Electronics Coolant Pump A Control Circuit High Likely for this code High
- P0B09 Electric/Auxiliary Transmission Fluid Pump A Motor Supply Voltage Circuit/Open Likely for this code High
- P2258 Secondary Air Injection System Control A Circuit High Likely for this code Moderate
- P2400 Evaporative Emission System Leak Detection Pump Control Circuit Open Likely for this code Moderate
- P2402 Evaporative Emission System Leak Detection Pump Control Circuit High Likely for this code Moderate
- P0232 Fuel Pump Secondary Circuit High Stop driving High
- P0B38 Motor Electronics Coolant Pump B Control Circuit/Open High
- P0B3A Motor Electronics Coolant Pump B Control Circuit High High
- P0C20 Electric/Auxiliary Transmission Fluid Pump Phase U-V-W Circuit/Open High
- P0C21 Electric/Auxiliary Transmission Fluid Pump Phase U-V-W Circuit Low Moderate
- P0C22 Electric/Auxiliary Transmission Fluid Pump Phase U-V-W Circuit High Moderate
- P0C26 Electric/Auxiliary Transmission Fluid Pump A Motor Current High
- P0C27 Electric/Auxiliary Transmission Fluid Pump A Motor Current Low Moderate
- P0C47 Hybrid/EV Battery Pack Coolant Pump A Control Circuit/Open High
- P0C48 Hybrid/EV Battery Pack Coolant Pump A Control Circuit Low High
- P0C49 Hybrid/EV Battery Pack Coolant Pump A Control Circuit High High
- P0C4A Hybrid/EV Battery Pack Coolant Pump A Control Performance High
- P0C4B Hybrid/EV Battery Pack Coolant Pump A Supply Voltage Circuit/Open High
- P0C4C Hybrid/EV Battery Pack Coolant Pump A Supply Voltage Circuit Low Moderate
- P0C4D Hybrid/EV Battery Pack Coolant Pump A Supply Voltage Circuit High Moderate
- P0CC1 Drive Motor A Coolant Pump Control Circuit/Open High
- P0CC2 Drive Motor A Coolant Pump Control Circuit Range/Performance Moderate
- P0CC3 Drive Motor A Coolant Pump Control Circuit Low Moderate
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.
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