Fault-Code Library · Turbocharging
P0046: Turbocharger boost-control circuit range / performance
Turbo actuator or boost-control response is outside the range expected by the ECU.
Common symptoms
- •Reduced power
- •Overboost or underboost
- •Intermittent limp mode
- •Poor acceleration
Likely causes
- •Sticking actuator or vanes
- •Boost solenoid fault
- •Vacuum leak
- •Wiring or calibration problem
First checks
- •Log requested and actual boost
- •Run an actuator sweep
- •Inspect vacuum supply, wiring, and linkage
Important
Avoid full-load testing until overboost has been ruled out and actuator control is understood.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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