P0CAB code meaning
Hybrid/EV Battery Temperature Sensor M Circuit High
Powertrain system Generic code P0Cxx codes Check engine light
What P0CAB means
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.
P0CAB at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.5 to 5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0CAB
- Battery shown as very cold in mild weather
- Reduced electric power, engine running more on plug-ins
Common causes of P0CAB
- Most likelyOpen circuit or unplugged connector of sensor M
- PossibleThermistor M open internally
- Less likelyCorroded or spread terminal at the monitoring board
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery temp sensor mWiring harnessBms
What each part of P0CAB means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| C | Area: hybrid propulsion. |
| AB | The exact fault in that area. |
What to do next
- Note P0CAB and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0CAB
What does P0CAB mean?
P0CAB means "Hybrid/EV Battery Temperature Sensor M Circuit High". P0CAB is logged when the input of sensor M rises beyond its upper voltage limit. It is a generic code, so it means the same on every make.
Is it safe to drive with P0CAB?
Drive gently and only to a workshop. With P0CAB the car can go into limp mode (reduced power) to protect itself.
Will P0CAB fail an emissions test?
Yes, it can. P0CAB is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0CAB to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 5 hours of work. This is a job for a workshop.
Will P0CAB clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.