Charge Air Cooler Bypass Control Circuit High
The P022F code indicates that the Powertrain Control Module (PCM) has detected a high voltage condition in the charge air cooler (CAC) bypass control circuit. This circuit controls a valve that diverts air around the intercooler to manage intake air temperature. A high voltage reading suggests a short to power, open circuit, or faulty component, which can lead to improper boost control and reduced engine performance.
1. Most Common Causes
- Short to voltage in the CAC bypass control circuit 'B' wiring
- Faulty CAC bypass actuator/solenoid (internal open circuit or driver failure)
- Damaged, corroded, or poor pin contact at the actuator connector
- Internal PCM driver (transistor) failure
- Ground circuit issues in the actuator causing a false high voltage reading
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or hesitation
- Poor fuel economy
- Possible turbocharger overboost or underboost
3. Step-by-Step Diagnosis
Step 1: Scan for additional codes and freeze frame data.
Step 2: Visually inspect the CAC bypass valve and wiring for damage or corrosion.
Step 3: Test the bypass valve resistance and compare to specifications.
Step 4: Check for voltage at the valve connector with key on; should be 5V reference signal.
Step 5: If wiring and valve are OK, test PCM output and replace PCM if necessary.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause reduced engine performance and potential damage to the turbocharger or engine due to improper air temperature management.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, depending on whether the valve or wiring needs replacement. Parts cost around $30-$80, labor $50-$100.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.