P2BDBMotor Electronics Coolant Temperature Sensor B Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2BDB tells that the signal of coolant temperature sensor B sits above its valid voltage range. With a thermistor fed from a 5 V reference through a pull-up resistor, a broken wire, an unplugged connector or a sensor gone open lets the voltage rise to almost the reference, which the module would read as extreme cold. No manufacturer documents P2BDB publicly. GM's sensor A counterpart on the 2013 Two-Mode hybrid trucks, P0A03, uses a limit of -59.1 °C and the same 30-of-50 count at 100 ms, Type B. Since real overheating would go unseen, controllers usually fall back to a safe pump speed or reduced power. P2BDA covers the grounded case, P2BD8 an unspecified circuit fault of the same sensor.
- What you may notice
- Check engine light or hybrid warning
- Scan tool shows an implausibly low electronics coolant temperature
- Electronics coolant pump running at a fixed high speed
- Likely causes
- LikelySensor B connector unplugged, not latched or with a backed-out pin
- PossibleBroken signal or ground wire of sensor B
- PossibleSensor B thermistor gone open
- RareSignal wire shorted to a voltage source
- 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.