The P0971: Pressure Control Solenoid ‘C’ Control Circuit High refers to an issue where the pressure control solenoid ‘C’ circuit is experiencing higher than expected voltage. This can lead to improper operation of the solenoid, causing transmission fluid pressure regulation problems and poor shifting performance.
P0971 – Quick Overview
Code | Information |
---|---|
Meaning | P0971: Pressure Control Solenoid ‘C’ Control Circuit High |
Is it serious? | Yes, as high voltage can cause solenoid malfunction, affecting transmission pressure control. |
Possible causes | – High voltage in the pressure control solenoid ‘C’ circuit – Faulty pressure control solenoid ‘C’ – Wiring or connector issues |
How to diagnose? | – Check the circuit for high voltage – Inspect wiring and connectors – Replace the pressure control solenoid ‘C’ if necessary |
P0971 Meaning
The P0971: Pressure Control Solenoid ‘C’ Control Circuit High code indicates that the voltage in the pressure control solenoid ‘C’ circuit is above the acceptable range. High voltage in this circuit can cause the solenoid to malfunction, leading to improper regulation of hydraulic pressure within the transmission, resulting in shifting problems and transmission damage over time.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for additional fault codes that may give more context about the high voltage issue. | OBD-II Scanner |
Test for High Voltage | Use a multimeter to test the voltage in the pressure control solenoid ‘C’ circuit. Compare the readings with the manufacturer’s specifications to confirm if the voltage is too high. | Multimeter |
Inspect Wiring and Connectors | Inspect the wiring and connectors for signs of damage, corrosion, or loose connections that could cause high voltage in the solenoid circuit. | Flashlight, Multimeter |
Test the Solenoid | Test the pressure control solenoid ‘C’ for proper operation. Replace the solenoid if it is malfunctioning or receiving excessive voltage. | Diagnostic Tool, Replacement Solenoid |
Clear the Code and Test Drive | After completing repairs, clear the code using an OBD-II scanner and take the vehicle for a test drive to ensure the issue is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | Re-scan the system to ensure the P0971 code does not reappear after the test drive. | OBD-II Scanner |

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