Engine-Codes - GMC - P0977 GMC

P0977 GMC Code - Shift Solenoid 'B' Open Or Short To Power

- Code Popularity: 2,844 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
Table of contents
ChatAC AutoCodes.com AI Chat

What are the Possible Causes of the DTC P0977 GMC?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Low transmission fluid level
  • Dirty transmission fluid
  • Faulty Transmission Control Solenoid Valve
  • Transmission Control Solenoid Valve harness is open or shorted
  • Transmission Control Solenoid Valve circuit poor electrical connection
⚠ Does your GMC have Safety Recalls? → Check here

How to Fix the DTC P0977 GMC?

Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

Search for P0977 GMC Questions and Answers: Search here →

What is the Cost to Diagnose the Code?

Labor: 1.0

The cost to diagnose the P0977 GMC code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

What Does the P0977 GMC Code Mean?

The shift solenoid 2 is part of the control solenoid valve assembly which has no serviceable parts. The shift solenoid 2 is a normally closed ON/OFF solenoid and is controlled by the Transmission Control Module through a low side driver. When the shift solenoid 2 is energized, shift solenoid 2 fluid pressure is directed to the clutch select valve 3. Power to the shift solenoid 2 is supplied by the Transmission Control Module through a high-side driver. The high-side driver protects the circuit and components from excessive current flow. If excessive current flow is detected, the high side driver will turn OFF. When the fault is corrected, the high-side driver will reset. The Diagnostic Trouble Code (DTC) will be set when the Transmission Control Module detects an internal high voltage electrical malfunction of the shift solenoid 2 control circuit when the shift solenoid 2 is commanded ON for 2 seconds.

P0977 GMC Code - Shift Solenoid 'B' Open Or Short To Power

Need more Information on the Code?

Need more information on how to fix the P0977 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0977 GMC code diagnosed by a professional: Find a repair shop in your area