P2B23 code meaning
Hybrid/EV Electronics Coolant Temperature Sensor B Circuit High
Powertrain system Generic code P2Bxx codes Check engine light
What P2B23 means
With P2B23 the signal of electronics coolant sensor B climbs close to the reference voltage. For an NTC sensor that reads as extreme cold, which in practice nearly always points to an interruption: an unplugged or water-damaged connector, a broken signal or ground lead, an open element, or more rarely a short to a voltage source. No manufacturer documents P2B23 publicly; NTN-SNR records it as signal too high for sensor B. GM's tables for the sibling sensor A code P0CF1 set above 98 % of the reference (4.9 V) for 4 s in a 5 s window, Type B with MIL after two trips. A real-world hint comes from sensor A on the Chrysler Pacifica Hybrid, where water in an inline connector caused the same kind of high reading. The grounded counterpart is P2B22.
P2B23 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2B23
- Hybrid or EV system warning with MIL
- Coolant temperature for sensor B shown at about −40 °C in live data
- Power reduced as a precaution
Common causes of P2B23
- Most likelyOpen signal or ground wire, or connector not fully seated
- PossibleWater intrusion and corroded pins in a connector of the sensor circuit
- PossibleSensor B element open
- Less likelySignal wire shorted to a voltage source
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hybrid electronics coolant temp sensor bWiring harnessHybrid control module
What each part of P2B23 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| B | Area: hybrid propulsion. |
| 23 | The exact fault in that area. |
What to do next
- Note P2B23 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 P2B23
What does P2B23 mean?
P2B23 means "Hybrid/EV Electronics Coolant Temperature Sensor B Circuit High". With P2B23 the signal of electronics coolant sensor B climbs close to the reference voltage. It is a generic code, so it means the same on every make.
Is it safe to drive with P2B23?
Drive gently and only to a workshop. With P2B23 the car can go into limp mode (reduced power) to protect itself.
Will P2B23 fail an emissions test?
Yes, it can. P2B23 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 P2B23 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will P2B23 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.