P0947: Hydraulic Pump Relay/Control Circuit Low
What to do
If you can hear the pump running constantly, or the battery goes flat when the car stands, do not leave it — continuous running destroys the pump, and the pump is the expensive part while the relay is not.
What this code means
The pump relay control circuit reads below its valid range, normally a short to ground, which generally leaves the relay energised whether the module wants it or not. The pump then runs continuously — overheating it, wearing it at many times its designed rate, and flattening the battery over a few days of standing.
Likely causes
Start here
- Wiring shorted to ground · moderate
- Faulty hydraulic pump relay · easy
- Welded relay contacts · easy
Less common
- Corroded or loose connector · easy
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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