P0035
Turbocharger/Supercharger Bypass Valve A Control Circuit High
Turbo / boost control
Generic OBD-II
High
What it means
P0035 means the ECM sees higher-than-expected voltage on the control circuit for the turbo/supercharger bypass (diverter) valve — the valve that vents boost pressure when you lift off the throttle. A fault here disrupts boost control, so you may notice reduced power, lag, or limp mode. It's an electrical issue in the circuit, usually the wiring or the valve, and it does not cause a no-start.
High
Can I keep driving? Usually yes, but with reduced boost and power; drive gently and repair soon to avoid limp mode and protect the turbo system.
Common symptoms
What you'll notice
- Check-engine light on
- Reduced boost and power
- Hesitation or lag under acceleration
- Possible limp mode
Common causes
Most likely first
- Open or short (high voltage) in the bypass valve control circuit (most common)Likely
- Corroded or loose connector at the valveCommon
- Faulty turbo/supercharger bypass (diverter) valveCommon
- Failed ECM (rare)Less often
How to diagnose & fix
Work through it in order
- Inspect the bypass valve connector and wiring for opens, shorts, or corrosion.
- Check the control-circuit voltage and the valve's resistance against spec.
- Verify power and ground to the circuit.
- Replace the bypass valve if it fails testing.
- If the circuit and valve are good, suspect the ECM. Clear and retest.
FAQ
Quick answers
Is it safe to drive with P0035?+
Short trips are usually fine, but you'll have reduced boost and may drop into limp mode. Repair soon to restore full power.
Can I just clear P0035?+
It will return while the circuit is faulted. Trace the wiring or replace the bypass valve before clearing.
Related codes
Often seen with P0035
Read & clear P0035 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX