Charge Air Cooler Bypass Control "A" Circuit High
This code means the PCM/ECM has detected a high-voltage circuit condition affecting charge air cooler bypass control "a. On turbocharged or supercharged engines, this can upset airflow and boost control, causing low power, poor acceleration, smoke, or limp mode.
What You Might Notice
- Check Engine Light illuminated
- Reduced boost or low power
- Poor acceleration
- Engine may enter limp mode
- Possible smoke under load
Most Common Causes
- 1
Short to voltage or an internally failed component
- 2
Faulty boost control solenoid, sensor, or actuator
- 3
Damaged wiring/connectors
- 4
Sticking wastegate or turbo/supercharger issue
- 5
PCM control fault
How to Diagnose It
- 1
Check Short to voltage or an internally failed component — Inspect for signs of failure and test before replacing.
- 2
Check Faulty boost control solenoid, sensor, or actuator — Inspect for signs of failure and test before replacing.
- 3
Check Damaged wiring/connectors — Inspect for signs of failure and test before replacing.
- 4
Check Sticking wastegate or turbo/supercharger issue — Inspect for signs of failure and test before replacing.
- 5
Check PCM control fault — Inspect for signs of failure and test before replacing.
How to Fix It
- 1
Pressure-test the intake/boost system for leaks
- 2
Inspect and repair wiring/connectors to the control solenoid or sensor
- 3
Test and replace the faulty boost-related component
- 4
Inspect the turbo/supercharger and wastegate for sticking or damage
- 5
Clear the code and confirm boost control during a road test
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