What it means
The PCM detected an open circuit or malfunction in Charge Air Cooler Bypass Control B. The code identifies a control-circuit fault; the exact component depends on the vehicle design.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Charge-air-cooler bypass control B operates a bypass mechanism in the intake-air cooling system; the exact hardware and circuit depend on the vehicle. The PCM monitors the B control circuit and sets P022D when it detects an open circuit or another malfunction that prevents expected control.
Common causes
Most likely first.
- Wiring break
- Pin pushed back out of connector body
- Cracked solder joint inside the module or sensor
Symptoms
- Check-engine light on
- Reduced engine power or acceleration
- Poor turbo response
- Reduced fuel economy
How to diagnose it
- Record freeze-frame data and scan for related boost, charge-air temperature, and bypass-control codes to identify when control B failed.
- Locate the charge-air-cooler bypass control B component using service information and inspect its connector for a pushed-back pin or poor fit.
- Trace the B-circuit wiring to the actuator or module and look for a break, damaged insulation, or loose supply or ground connections.
- Use available scan-tool actuator commands or status data to check whether the B control responds when commanded.
- Test the B circuit and identified actuator or module according to the wiring diagram and manufacturer's specification.
Common fixes
- Reseat a loose connector or pushed-back B-circuit terminal.
- Repair a broken wire or poor connection in the B control circuit.
- Repair a cracked solder joint if testing identifies it within a serviceable module.
- Replace the failed B bypass actuator or control module only after circuit tests confirm the fault.
Can I keep driving?
If power is reduced or turbo response is poor, avoid towing, steep climbs, and hard acceleration because the vehicle may not deliver expected power. Arrange diagnosis soon if the loss of power makes it difficult to keep up with traffic.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.