P0977 Fault Code

Shift Solenoid B Control Circuit High

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0977 fault code indicates a problem with the shift solenoid B control circuit where the signal is reading high. This issue can disrupt the vehicle's transmission performance and lead to erratic shifting behavior.

What are the symptoms of the P0977 code?

Symptoms may include:

• Harsh or erratic shifting of gears
• Transmission slipping or refusal to shift
• Check Engine Light illuminates
• Decreased fuel efficiency due to improper gear changes.

What causes the P0977 code?

Common causes of this fault code include:

• Faulty shift solenoid B
• Damaged wiring or connectors in the shift solenoid circuit
• Faulty transmission control module (TCM)
• Low transmission fluid levels
• Internal transmission issues such as valve body problems.

How to fix P0977?

To resolve the P0977 fault code, consider the following steps:

• Inspect and repair any damaged wiring or connectors to the shift solenoid B.
• Replace the faulty shift solenoid B if needed.
• Check transmission fluid levels and condition, topping off or changing as necessary.
• Perform a diagnostic scan to reset the code after repairs and test drive to ensure the issue is resolved.