Short to voltage on the boost control solenoid supply circuit (damaged wire insulation or connector); Failed boost control solenoid with an open internal coil; Corroded or loose electrical connector at the solenoid; Faulty ground connection for the boost control circuit; Damaged or shorted wiring harness between the PCM and solenoid; Internal PCM driver failure (less common); Aftermarket electrical accessories improperly tapped into the circuit

DTC codes / P00xx · Fuel and air metering and auxiliary emission controls / P005F

P005FTurbocharger/Supercharger Boost Control B Supply Voltage Circuit High

P005F indicates that the powertrain control module has detected an abnormally high voltage on the supply circuit for the 'B' turbocharger or supercharger boost control solenoid. This typically means the control wire is shorted to voltage, the solenoid's internal coil is open, or the ground reference is compromised, causing the module to see voltage above the expected range.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering and auxiliary emission controls

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Reduced engine power or limp mode due to disabled boost control
Poor acceleration and sluggish throttle response
Decreased fuel economy from incorrect boost pressure
Possible overboost or underboost conditions depending on the failure mode
In rare cases, a noticeable whistling or hissing noise from the turbocharger area

Common causes, most likely first

Short to voltage on the boost control solenoid supply circuit (damaged wire insulation or connector)
Failed boost control solenoid with an open internal coil
Corroded or loose electrical connector at the solenoid
Faulty ground connection for the boost control circuit
Damaged or shorted wiring harness between the PCM and solenoid
Internal PCM driver failure (less common)
Aftermarket electrical accessories improperly tapped into the circuit

How to diagnose and fix it

Inspect the boost control solenoid connector and wiring for corrosion, chafing, or loose pins
Disconnect the solenoid and measure resistance across its terminals to check for an open coil
With the key on and solenoid disconnected, measure voltage on the supply wire to ground; it should be near battery voltage only when commanded
Check for a short to voltage by measuring the control wire with the PCM disconnected; any voltage indicates a short
Verify the ground circuit integrity by measuring resistance from the solenoid ground pin to battery negative
If wiring and solenoid test good, suspect the PCM and perform a driver circuit test with a bidirectional scan tool
Repair or replace the faulty component and clear the code, then verify the boost control operates correctly

Boost control circuit checks before parts

A common oversight is assuming the solenoid is bad when a chafed wire shorting to a nearby power source is the real cause.
The code can set intermittently due to vibration or heat, so a wiggle test of the harness while monitoring live data is essential.
Some vehicles use a PWM signal on the supply circuit; a standard multimeter may not show the true average voltage, so an oscilloscope is more reliable.
Replacing the solenoid without checking the ground circuit often leads to a repeat failure because a bad ground can mimic a short to voltage.
This code does not always mean the turbocharger itself is failing; the fault is electrical and may not affect boost if the solenoid defaults to a safe position.

Can I keep driving with P005F?

You can usually drive the vehicle with this code, but expect reduced power and possible limp mode; avoid heavy acceleration and towing until the fault is repaired to prevent further damage to the turbocharger or engine.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.