Turbocharger Wastegate Solenoid B High
P0250 indicates the PCM detected a high voltage condition on the wastegate/boost pressure control solenoid B circuit. This solenoid regulates turbocharger boost pressure, and the fault prevents proper boost control, reducing engine power and efficiency.
What You Might Notice
- Malfunction Indicator Light (MIL) illuminated
- Lack of engine power or reduced boost pressure
- Instrument cluster warning message
- Possible black smoke or rough idle
- Reduced fuel economy
Most Common Causes
- 1
Wastegate solenoid short to power
The solenoid control circuit is shorted to power, causing excessive voltage at the PCM control pin. This prevents the PCM from properly commanding the solenoid.
- 2
Wiring harness damage or short
Damaged insulation on the control circuit between the solenoid and PCM creates an accidental short to the vehicle's power supply. Check for pinches, cuts, or corrosion.
- 3
Wastegate solenoid failure
The solenoid has an internal short or failed coil winding, causing continuous current draw and high voltage at the control pin.
- 4
PCM control circuit malfunction
A faulty PCM driver circuit or connector issue prevents the module from properly grounding the solenoid control line, resulting in high voltage.
How to Diagnose It
- 1
Check Wastegate solenoid short to power — The solenoid control circuit is shorted to power, causing excessive voltage at the PCM control pin. This prevents the PCM from properly commanding the solenoid.
- 2
Check Wiring harness damage or short — Damaged insulation on the control circuit between the solenoid and PCM creates an accidental short to the vehicle's power supply. Check for pinches, cuts, or corrosion.
- 3
Check Wastegate solenoid failure — The solenoid has an internal short or failed coil winding, causing continuous current draw and high voltage at the control pin.
- 4
Check PCM control circuit malfunction — A faulty PCM driver circuit or connector issue prevents the module from properly grounding the solenoid control line, resulting in high voltage.
How to Fix It
- 1
Inspect and repair wiring harness
Visually inspect the entire control circuit between the solenoid and PCM for damage, corrosion, or shorts. Repair any damaged insulation or replace the affected wiring section.
- 2
Test and replace wastegate solenoid
Use a multimeter to test the solenoid's resistance and voltage behavior. If testing confirms the solenoid is defective, replace it with an OEM or quality aftermarket unit.
- 3
Check PCM connector pins
Inspect the PCM connector for loose pins, corrosion, or damage on the solenoid control line. Clean contacts with electrical contact cleaner and reseat the connector firmly.
- 4
Verify power and ground circuits
Use a voltmeter to confirm proper voltage supply to the solenoid and verify ground continuity. Test from the battery through the relevant fuses and relays to isolate any supply-side issues.
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