Turbo Bypass Valve Control Circuit High
The P0035 code indicates that the Powertrain Control Module (PCM) has detected a high voltage condition in the control circuit of the turbocharger bypass valve (also known as the wastegate solenoid). This valve regulates boost pressure by diverting exhaust gases away from the turbine. A high voltage signal suggests a short to power, open circuit, or faulty component, which can lead to overboost or underboost conditions, potentially causing engine damage.
01. Most Common Causes
- Faulty turbocharger bypass valve solenoid
- Short to power in the control circuit wiring
- Open or shorted wiring harness
- Corroded or damaged connector
- Failed PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or limp mode
- Poor acceleration
- Excessive turbo lag or surging
- Possible overboost condition
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect the bypass valve connector and wiring for damage, corrosion, or shorts.
Step 3: Test the bypass valve solenoid resistance with a multimeter (compare to specs).
Step 4: Check for voltage at the solenoid connector with key on; should be battery voltage on one pin.
Step 5: Command the valve on/off with a scan tool and verify operation.
Step 6: If wiring and valve are good, test PCM output or replace PCM.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Driving with P0035 can cause overboost or underboost, potentially damaging the turbo or engine. Limp mode may limit speed, but continued driving risks costly repairs.
How much does it cost to fix?▼
Typical repair costs range from $50 to $150 for parts (bypass valve solenoid) plus labor. If wiring repair is needed, costs may increase. DIY replacement is possible for some vehicles.