P0951 Auto Shift Manual Control Circuit Range Performance

OBD2 Code: P0951

Description: Auto Shift Manual Control Circuit Range Performance

Definition: This code indicates that there is a problem with the performance of the auto shift manual control circuit. The transmission control module (TCM) has detected an issue with the range or performance of this circuit, which may affect the vehicle’s ability to manually shift gears.

P0951 – Auto Shift Manual Control Circuit Range Performance

Typical Severity: Moderate

Common Causes

P0951 – Auto Shift Manual Control Circuit Range Performance

Common causes:

• Faulty auto shift manual control switch
• Open or short circuit in the auto shift manual control circuit
• Corroded or loose connections in the auto shift manual control circuit
• Defective transmission range sensor
• Low transmission fluid level or dirty transmission fluid

 

Common Misdiagnosis

OBD2 Code: P0951

Description: Auto Shift Manual Control Circuit Range/Performance

Common Misdiagnosis: Replacing the transmission control module (TCM) without checking for wiring issues or faulty shift solenoids.

 

Common Diagnostic Steps

OBD2 Code: P0951

Description: Auto Shift Manual Control Circuit Range/Performance

Common Diagnostic Steps:

• Check for any additional trouble codes that may be present and address those first.
• Inspect the wiring and connectors related to the auto shift manual control circuit for damage, corrosion, or loose connections.
• Test the voltage and ground signals at the transmission control module (TCM) to ensure they are within specifications.
• Verify that the shift lever is functioning correctly and is not physically obstructed or damaged.
• Use a scan tool to monitor live data from the TCM to check for abnormal readings in the shift position sensor.
• If applicable, update the vehicle’s software to ensure it has the latest calibration files.
• If all else fails, consider replacing faulty components such as the shift position sensor or TCM after confirming their failure through testing.