P0781

What does P0781 mean?

P-code P0781 means "Pressure Control Solenoid B Stuck On". It is a generic OBD-II diagnostic trouble code (DTC) in the powertrain. The pressure reading from the pressure control solenoid b stuck on is outside the expected operating range. This code can be monitored, but service is recommended to prevent escalation. This code applies to OBD-II compliant electric and hybrid vehicles.

Possible Causes

• Faulty pressure sensor or damaged sensor connector
• Fluid leak causing lower-than-expected pressure readings
• Blocked pressure port or contaminated sensing element
• Pump or actuator failure affecting system pressure

Recommended Actions

1. 1 Note the alert and schedule a diagnostic appointment when convenient
2. 2 Scan for all DTCs with an OBD-II scanner — note any related codes stored alongside P0781
3. 3 Inspect the mechanical component for physical obstruction, ice, or debris
4. 4 Manually operate (if safe) to check for binding or unusual resistance
5. 5 Clear the DTC, road-test the vehicle, and re-scan to confirm whether the fault returns
6. 6 If the fault persists after inspection and clearing, consult an EV-certified technician for component replacement

Related Powertrain fault codes