P0035: Turbocharger/Supercharger Bypass Valve A Control Circuit High

The turbocharger bypass valve A is the compressor recirculation (diverter) valve: it connects the pressure side of the compressor with the intake side upstream of the turbocharger. It opens when the throttle closes quickly at high boost, so the compressor does not surge and the compressor wheel keeps its speed for the next acceleration. It is not the wastegate, which bypasses exhaust gas around the turbine and has its own codes. The valve is either electric or a vacuum unit controlled by a solenoid. P0035 means the voltage at the control output is too high, typically a short to battery voltage; on some engines an intermittent break in the harness has also set this code.

Medium severity. Can I keep driving?Drive without demanding power and go to a repair shop soon. If you see a lot of blue smoke or hear a metallic noise, shut off the engine.

Symptoms

Check engine light on
Fluttering or hissing when lifting off the throttle if the valve stays closed
Weak response after gear changes
Too little boost if the valve stays open

Most likely causes

Control wire shorted to battery voltage
Loose contact or broken wire, e.g. harness vibrating from heat
Solenoid coil faulty
Output driver in the engine control module faulty

What to check, in order

Start with the simplest. You can tick off each step.

Check the hoses, clamps, and intercooler
Check the sensor's ground and make sure the signal wire is not receiving voltage from another circuit.
Compare commanded and actual pressure in live data
Check the actuator's movement
Check the vacuum hoses and the solenoid valve
Check the oil and the turbo shaft play before replacing it

Good to know

Repair difficulty: medium
It affects emissions.

What each character of P0035 means

P: Powertrain: engine and transmission
0: Generic code: same on every make
0: Subsystem depends on the code range
35: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0035?

Drive without demanding power and go to a repair shop soon. If you see a lot of blue smoke or hear a metallic noise, shut off the engine.

What causes code P0035?

The most common causes are: control wire shorted to battery voltage; loose contact or broken wire, e.g. harness vibrating from heat; solenoid coil faulty.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.