P0CABHybrid/EV Battery Temperature Sensor M 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
- P0CAB is logged when the input of sensor M rises beyond its upper voltage limit. If the thermistor, one of its wires or the plug opens up, the pull-up resistor lifts the input, and the controller reads a temperature far below anything plausible. GM's HPC2 table 18OBDG02 sets it when 8 of 10 readings at 100 ms intervals are colder than −69 °C, as a Type B fault needing over 10.2 V and intact communication. In the 2011 Volt table the limit was −40 °C, a raw count above 4,000, held 1.4 s within 2 s, and a single trip was enough. Mitsubishi treats it as an open circuit of sensor [12] on the Outlander PHEV: above 3.97 V, below about −62 °C, for 2 s. A plug-in may then heat its battery needlessly or start the engine; P0CAA is the low partner.
- What you may notice
- Battery shown as very cold in mild weather
- Reduced electric power, engine running more on plug-ins
- Likely causes
- LikelyOpen circuit or unplugged connector of sensor M
- PossibleThermistor M open internally
- RareCorroded or spread terminal at the monitoring board
- 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: €100 – €3,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.