P0CB4Hybrid/EV Battery Temperature Sensor O Circuit Low
- 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
- P0CB4 reports a signal voltage of sensor O below its lower limit. The sensor is an NTC thermistor biased by a resistor on the measuring board, so a short to ground or a shorted element looks like extreme heat. GM's HPC2 table 18OBDG02 fails the test when the converted value is above 160 °C in 8 of 10 readings at 100 ms, Type B, with more than 10.2 V supply; the 2011 Volt table used 87.5 °C, a raw count below 680, for 1.4 s within a 2 s window over two trips. In GM's 2019 table the pack over-temperature monitor P0A7E is suspended while such short codes are active, because a false hot reading would otherwise trigger it. Mitsubishi calls P0CB4 a short of module sensor [14] on the Outlander PHEV: under 0.12 V, roughly above 125 °C, for 2 s.
- What you may notice
- Live data showing an implausibly hot module
- Strongly reduced battery power with warning lamp
- Battery cooling running without obvious need
- Likely causes
- LikelySignal lead of sensor O shorted to ground in the pack
- PossibleThermistor O shorted internally
- RareInput stage of the cell monitoring unit defective
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €150 – €3,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.