Turbo/Supercharger Boost Control Circuit Open
The P0045 code indicates an open circuit in the turbocharger or supercharger boost control solenoid circuit. This solenoid regulates boost pressure by controlling vacuum or pressure to the wastegate actuator. An open circuit means the electrical path is broken, preventing the solenoid from operating correctly, which can lead to overboost or underboost conditions.
01. Most Common Causes
- Faulty boost control solenoid
- Open or shorted wiring in the solenoid circuit
- Corroded or damaged connector
- Blown fuse or relay
02. Symptoms You Will Notice
- Check Engine Light on
- Loss of engine power or acceleration
- Overboost or underboost condition
- Possible limp mode activation
03. Step-by-Step Diagnosis
Step 1: Scan for codes and verify P0045 is present.
Step 2: Visually inspect the boost control solenoid and its wiring for damage or corrosion.
Step 3: Test the solenoid resistance with a multimeter (typically 15-30 ohms).
Step 4: Check for voltage and ground at the solenoid connector with ignition on.
Step 5: If wiring and solenoid are good, 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 power, poor fuel economy, and potential engine damage from overboost.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, including parts and labor, depending on the cause and vehicle.