P0A99: Hybrid/EV Battery Pack Cooling Fan 2 Control Circuit Low
What to do
As P0A84 — wiring first, and clean the fan while access is open.
What this code means
The second battery cooling fan's control circuit reads low — shorted to ground, or open where the resting state reads high. An electrical diagnosis per P0A84: wiring, connector, then the fan's speed controller.
Likely causes
Start here
- Wiring shorted to ground · moderate
- Faulty hybrid battery cooling fan · moderate
- Corroded or loose connector · easy
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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