P2CAD code meaning
Charge Air Cooler Coolant Pump B Control Circuit/Open
Powertrain system Generic code P2Cxx codes Check engine light
What P2CAD means
Where a charge air cooling loop has a second electric pump, it carries the letter B. P2CAD reports that the control line to that pump is open, so the driver stage in the engine computer sees no load. No manufacturer documents a pump B or this code publicly. GM publishes the matching test for pump A (P023A) on the supercharged LT5 in table 19OBDG03A: with the low-side driver switched off, more than 200 kΩ between output and ground counts as open; 50 failed samples out of 63 at 100 ms, main relay at least 11 V, Type A with MIL on the first trip. Unplugged or corroded connectors, a broken wire or an open motor winding are the common finds. A pump driven only over LIN has no such line and would report through U01BC instead.
P2CAD 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 P2CAD
- MIL on, often after the first trip
- Pump B silent; charge air temperature rises under load
- Reduced engine power
Common causes of P2CAD
- Most likelyPump B connector loose, unplugged or corroded
- PossibleBroken control wire between engine module and pump B
- PossibleOpen motor winding or internal board fault in pump B
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Cac coolant pump bWiring harnessECM
What each part of P2CAD means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| C | Area: hybrid propulsion. |
| AD | The exact fault in that area. |
What to do next
- Note P2CAD 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 P2CAD
What does P2CAD mean?
P2CAD means "Charge Air Cooler Coolant Pump B Control Circuit/Open". Where a charge air cooling loop has a second electric pump, it carries the letter B. It is a generic code, so it means the same on every make.
Is it safe to drive with P2CAD?
Drive gently and only to a workshop. With P2CAD the car can go into limp mode (reduced power) to protect itself.
Will P2CAD fail an emissions test?
Yes, it can. P2CAD 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 P2CAD to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will P2CAD clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.