Fix P0977: STEP-BY-STEP diagnostic GUIDE!

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

CodeInformation
MeaningP0977: 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

ActionDescriptionTools Needed
Check for Other CodesUse 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 VoltageUse 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 ConnectorsInspect the wiring and connectors for damage, corrosion, or loose connections that could cause high voltage in the solenoid circuit.Flashlight, Multimeter
Test the SolenoidTest 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 DriveAfter 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 CodesRe-scan the system to ensure the P0977 code does not reappear after the test drive.OBD-II Scanner
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