P2BDE code meaning
Motor Electronics Coolant Temperature Sensor C Circuit Low
Powertrain system Generic code P2Bxx codes Check engine light
What P2BDE means
P2BDE reports that the voltage from coolant temperature sensor C has dropped below its lower limit. Low describes the voltage: for the usual NTC sensor it corresponds to a reading far hotter than the coolant can be, and the cause is mostly a grounded signal wire, a crushed pigtail or a sensor that has shorted internally. No manufacturer documents P2BDE publicly. GM's electronics coolant sensor in the Volt and ELR, monitored as P0CF0, shows typical limits: below 2 % of the 5 V reference (0.1 V) in the 2011 tables and below 4 % (0.2 V) in the 2016 Volt table, 16 of 20 samples at 250 ms, Type B. The open or high case is P2BDF, while the matching low fault of sensor B is P2BDA. Drive power may be limited as a precaution.
P2BDE at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2BDE
- Hybrid warning or check engine light
- Very high electronics coolant temperature shown in live data on a cold vehicle
- Fan running at full speed shortly after start
Common causes of P2BDE
- Most likelySensor C signal wire shorted to ground or to the sensor ground
- PossibleSensor C shorted internally
- PossibleCrushed or melted sensor pigtail near hot components
- Less likelyFaulty analog input in the evaluating module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Motor electronics coolant temp sensor cWiring harnessHybrid control module
What each part of P2BDE 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. |
| DE | The exact fault in that area. |
What to do next
- Note P2BDE 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 P2BDE
What does P2BDE mean?
P2BDE means "Motor Electronics Coolant Temperature Sensor C Circuit Low". P2BDE reports that the voltage from coolant temperature sensor C has dropped below its lower limit. It is a generic code, so it means the same on every make.
Is it safe to drive with P2BDE?
Drive gently and only to a workshop. With P2BDE the car can go into limp mode (reduced power) to protect itself.
Will P2BDE fail an emissions test?
Yes, it can. P2BDE 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 P2BDE to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will P2BDE clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.