P0BC7: Hybrid/EV Battery Pack Cooling Fan 1 Sense Circuit/Open
What to do
Look for the cheap one first: the battery's cooling intake is usually inside the car — under a rear seat, in the boot side trim, or behind a parcel shelf vent — and it blocks with dust and debris. Clearing it is free and fixes a real share of these. Beyond that, this code means the car cannot confirm its battery is being cooled, which is worth attending to before hot weather or a long fast-charging trip.
What this code means
The circuit that reports what the battery cooling fan is actually doing has failed or gone open.
This is the sense circuit, and the distinction from the control circuit is the reason it exists. The control circuits — Fan 1 at P0480, Fan 2 at P0A96, Fan 3 at P0AC5 — are the module commanding the fan. This one is the fan reporting back: a tachometer output, or a current feedback, saying how fast it is really turning.
Without it, a module can only know what it asked for. A fan whose bearings have seized, whose blades are jammed by debris, or which is straining against a blocked intake will accept the command and do nothing useful, and a control circuit alone cannot tell. The sense circuit is what turns "I told the fan to run" into "the fan ran", which on a component protecting a very expensive battery is worth a code of its own.
Check the cheap thing first: the pack's cooling intake is often inside the cabin — under a rear seat or behind a side trim — and it collects dust, carpet fibre and anything left on the back seat. A blocked intake makes a healthy fan work hard and report wrongly.
Likely causes
Start here
- Blocked hybrid battery cooling fan intake · easy
- Faulty hybrid battery cooling fan · moderate
- Corroded or loose connector · easy
Less common
- Failed cooling fan motor · 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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