P0BCAHybrid/EV Battery Pack Cooling Fan 1 Sense Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P0BCA means the speed feedback of battery cooling fan 1 is implausibly high. GM's 2016 and 2018 hybrid tables count a failure when the feedback frequency exceeds 290 Hz with the fan enabled at 11 to 89 % duty for more than 8 s and system voltage above 10.2 V; 16 failures in 20 samples at 250 ms set it as Type B, two trips. No real fan reaches that frequency, so the cause is electrical: noise coupled into the feedback line, a line shorted to another signal or to voltage, or fan electronics sending garbage. Check wire routing and grounds before replacing the fan. The low case is P0BC9, speed errors within range P0BC8, an open line P0BC7. While the feedback is untrusted the controller may limit power.
- What you may notice
- MIL on after two trips
- Implausible fan speed reading on the scan tool
- Possible power reduction
- Likely causes
- PossibleElectrical noise on the feedback line from poor routing or a bad ground
- PossibleFeedback wire shorted to voltage or another signal
- PossibleFan electronics sending an invalid speed signal
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €40 – €500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.