P0C47: Hybrid/EV Battery Pack Coolant Pump A Control Circuit/Open
What to do
As P0C47 — expect slower charging and reduced power in warm weather until it is fixed. Ask for the supply to be checked before the pump is condemned; they produce identical symptoms and one is far cheaper.
What this code means
The circuit commanding the battery pack's coolant pump is open or faulty.
On a liquid-cooled pack this pump is what keeps the battery inside the temperature band where it may be charged quickly and discharged hard. It also runs when the car is switched off — during charging, and often for a period afterwards to carry heat out of a pack that has just been worked — so a fault here shows up as slow charging at least as often as it shows up while driving.
The control circuit is the command; the supply at P0C4B is the power. As everywhere in this block, the two are worth telling apart before a pump is bought: a pump correctly commanded with no supply behaves exactly like a failed pump.
Likely causes
Start here
- Faulty electric coolant pump · moderate
- Corroded or loose connector · easy
- Air trapped in the inverter cooling circuit · moderate
Less common
- Low coolant level · easy
- Open circuit in pump wiring · moderate
Symptoms
Components involved
Information, not instruction
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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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