Charge Air Cooler Bypass Control Circuit Low
The P022B code indicates that the Powertrain Control Module (PCM) has detected a low voltage condition in the charge air cooler (CAC) bypass control circuit. This circuit controls a valve that bypasses the intercooler to manage intake air temperature. A low voltage signal suggests a short to ground, open circuit, or faulty component, potentially affecting engine performance and emissions.
01. Most Common Causes
- Faulty charge air cooler bypass valve
- Short to ground in the bypass control circuit wiring
- Open circuit or poor connection in the bypass control circuit
- Failed PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or performance
- Poor fuel economy
- Possible rough idle or hesitation
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to retrieve all codes and freeze frame data.
Step 2: Visually inspect the bypass valve and wiring for damage, corrosion, or loose connections.
Step 3: Test the bypass valve resistance and compare to manufacturer specs.
Step 4: Check for voltage and ground at the valve connector using a multimeter.
Step 5: If wiring and valve are okay, test the PCM output signal.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause reduced performance and potential engine damage. Seek repair soon.
How much does it cost to fix?▼
Typical repair costs range from $50 to $150 for parts and labor, depending on the cause and vehicle.