Charge Air Cooler Bypass Control Range/Performance
The P024A code indicates that the Engine Control Module (ECM) has detected a performance or range issue with the charge air cooler (CAC) bypass control system. This system regulates airflow through the CAC to optimize intake air temperature and engine performance. The bypass valve may be stuck, operating incorrectly, or the circuit may have an electrical fault, causing the ECM to see an unexpected position or response.
01. Most Common Causes
- Faulty charge air cooler bypass valve
- Stuck or binding bypass valve due to carbon buildup
- Wiring or connector issues in the bypass valve circuit
- Failed ECM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or performance
- Poor fuel economy
- Possible turbocharger lag or overboost
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm P024A and check for other codes.
Step 2: Visually inspect the bypass valve and its wiring for damage or corrosion.
Step 3: Test the bypass valve operation using a scan tool to command it open/closed.
Step 4: Check the valve's resistance and compare to manufacturer specs.
Step 5: If wiring and valve are okay, test the ECM output signal.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is generally safe for short trips, but reduced performance and potential for further damage if the valve is stuck in a position causing overboost or excessive intake temperatures. Have it diagnosed promptly.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, including parts (bypass valve $50-$150) and labor (1-2 hours).