P04A6
Exhaust Pressure Control Valve B Position Sensor Circuit
A circuit fault is detected on the position sensor of exhaust pressure control valve B. Without valid position feedback the ECU cannot run closed-loop control of the valve and falls back to a default substitute.
A circuit fault is detected on the position sensor of exhaust pressure control valve B. Without valid position feedback the ECU cannot run closed-loop control of the valve and falls back to a default substitute.
Common causes
- high
Open in sensor signal, supply or ground
One of the most commonly reported causes for this code — check this first.
Typical part cost: $170-550
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P04A6 mean?
P04A6 means "Exhaust Pressure Control Valve B Position Sensor Circuit". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P04A6?
open in sensor signal, supply or ground — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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