The P0977: Shift Solenoid ‘B’ Control Circuit High refers to an issue where the shift solenoid ‘B’ control circuit is experiencing higher than expected voltage. This can cause the solenoid to malfunction, affecting the vehicle’s transmission shifting performance.
P0977 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0977: Shift Solenoid ‘B’ Control Circuit High |
| Is it serious? | Yes, high voltage can cause improper shifting and damage to the solenoid, affecting transmission performance. |
| Possible causes | – High voltage in the shift solenoid ‘B’ control circuit – Faulty shift solenoid ‘B’ – Wiring or connector issues |
| How to diagnose? | – Check the circuit for high voltage – Inspect wiring and connectors – Replace the shift solenoid ‘B’ if necessary |
P0977 Meaning
The P0977: Shift Solenoid ‘B’ Control Circuit High code indicates that the voltage in the shift solenoid ‘B’ control circuit is above the expected level. This excessive voltage can prevent the solenoid from functioning properly, leading to improper transmission fluid flow and shifting issues.
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 provide more insight into the high voltage issue. | OBD-II Scanner |
| Test for High Voltage | Use a multimeter to check for high voltage in the shift solenoid ‘B’ control circuit. Compare the voltage readings with manufacturer specifications. | Multimeter |
| Inspect Wiring and Connectors | Inspect the wiring and connectors for damage, corrosion, or loose connections that could cause high voltage in the solenoid circuit. | Flashlight, Multimeter |
| Test the Solenoid | Test the shift solenoid ‘B’ for proper operation. Replace the solenoid if it is faulty or receiving excessive voltage. | Diagnostic Tool, Replacement Solenoid |
| Clear the Code and Test Drive | After making 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 P0977 code does not reappear after the test drive. | OBD-II Scanner |
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