Powertrain
Definition only
Lights the check engine lamp
P2CB9: Fan 2 Underspeed
Standardized SAE J2012 code · P2Cxx codes
What does P2CB9 mean?
Cooling fan 2 runs below the calibrated minimum speed for the commanded duty. Mechanical resistance high or motor weakened.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Fan motor bearing worn
- Medium Supply voltage low under load
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2CB9 on the same make and model first.
P2CB9 in the community
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