P0971: Pressure Control Solenoid C Control Circuit High — what it means, the affected system and what to check before replacing parts.
Meaning, symptoms, causes and checks
Pressure-control solenoid C command: The electrical input is above its permitted range. This is an electrical finding, not an instruction to replace the monitored component. The letter C identifies a control channel, not a universal valve location. An electrical control-circuit result must be distinguished from the valve's hydraulic response.
Affected system: Transmission pressure-control solenoids
Symptoms
- An engine or transmission warning may be accompanied by harsh or irregular gear changes.
- The transmission may enter a restricted shifting mode when solenoid C control is unreliable.
Possible causes
- Broken, damaged or shorted wiring in pressure-control solenoid C's electrical control circuit.
- Loose or corroded electrical connectors or a faulty pressure-control solenoid C.
What to check
- Read relevant transmission codes and check vehicle-specific service information.
- Inspect the solenoid C harness and connectors for damaged insulation, looseness and corrosion.
- Test circuit voltage, continuity and solenoid resistance against the vehicle's specifications before replacing parts; a high electrical signal does not prove high fluid pressure.
Also written as: P0971-00, P097100, PO971 (some scan tools add the fault-type byte, e.g. -00).