P0758: Shift Solenoid B Electrical

Definition

The OBD2 code P0758 indicates a malfunction in the electrical circuit of Shift Solenoid B, which is responsible for controlling gear shifts in an automatic transmission

Common causes

Faulty shift solenoid B
Wiring issues (shorts, open circuits)
Poor electrical connections
Transmission control module (TCM) failure
Low transmission fluid levels
Contaminated transmission fluid
Faulty transmission valve body
Internal transmission problems

Common misdiagnoses

Transmission fluid issues
Faulty transmission control module (TCM)
Wiring or connector problems
Shift solenoid A failure
Internal transmission damage
Engine control module (ECM) issues
Incorrect transmission fluid type or level
Valve body problems

Troubleshooting steps

1. Check for Additional Codes

Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide more context and help identify related issues
2. Inspect Wiring and Connectors
3. Visually inspect the wiring and connectors associated with the shift solenoid B. Look for signs of damage, corrosion, or loose connections
4. Ensure that the connectors are securely attached and that there are no broken wires
5. Test the Shift Solenoid
6. Use a multimeter to test the resistance of the shift solenoid B. Compare the readings to the specifications provided in the vehicle's service manual
7. If the solenoid is out of specification, it may need to be replaced
8. Check Transmission Fluid
9. Inspect the transmission fluid level and condition. Low or dirty fluid can cause shifting issues
10. If the fluid is low, top it off with the correct type of transmission fluid. If it is dirty or burnt, consider a transmission fluid change
11. Inspect the Transmission Control Module (TCM)
12. Check for any issues with the TCM, which controls the operation of the shift solenoids. Ensure that it is functioning properly and that there are no software issues
13. If necessary, reprogram or replace the TCM
14. Test the Electrical Circuit
15. Use a multimeter to check for voltage and ground at the shift solenoid connector while the vehicle is in the appropriate gear
16. If there is no voltage or ground, trace the wiring back to the TCM to identify any breaks or shorts
17. Check for Mechanical Issues
18. Inspect the transmission for any mechanical problems that could affect the operation of the shift solenoid, such as sticking valves or internal wear
19. If necessary, perform a more in-depth inspection of the transmission
20. Clear Codes and Test Drive
21. After performing repairs or replacements, clear the trouble codes using the OBD-II scanner
22. Take the vehicle for a test drive to see if the code returns and if the transmission shifts properly
23. Consult a Professional
24. If the issue persists after performing these steps, it may be best to consult a professional mechanic or transmission specialist for further diagnosis and repair. By following these troubleshooting steps, you can identify and resolve the underlying issue causing the P0758 code

Definition

Common causes

Common misdiagnoses

Troubleshooting steps

1. Check for Additional Codes

2. Inspect Wiring and Connectors

3. Visually inspect the wiring and connectors associated with the shift solenoid B. Look for signs of damage, corrosion, or loose connections

4. Ensure that the connectors are securely attached and that there are no broken wires

5. Test the Shift Solenoid

6. Use a multimeter to test the resistance of the shift solenoid B. Compare the readings to the specifications provided in the vehicle's service manual

7. If the solenoid is out of specification, it may need to be replaced

8. Check Transmission Fluid

9. Inspect the transmission fluid level and condition. Low or dirty fluid can cause shifting issues

10. If the fluid is low, top it off with the correct type of transmission fluid. If it is dirty or burnt, consider a transmission fluid change

11. Inspect the Transmission Control Module (TCM)

12. Check for any issues with the TCM, which controls the operation of the shift solenoids. Ensure that it is functioning properly and that there are no software issues

13. If necessary, reprogram or replace the TCM

14. Test the Electrical Circuit

15. Use a multimeter to check for voltage and ground at the shift solenoid connector while the vehicle is in the appropriate gear

16. If there is no voltage or ground, trace the wiring back to the TCM to identify any breaks or shorts

17. Check for Mechanical Issues

18. Inspect the transmission for any mechanical problems that could affect the operation of the shift solenoid, such as sticking valves or internal wear

19. If necessary, perform a more in-depth inspection of the transmission

20. Clear Codes and Test Drive

21. After performing repairs or replacements, clear the trouble codes using the OBD-II scanner

22. Take the vehicle for a test drive to see if the code returns and if the transmission shifts properly

23. Consult a Professional

24. If the issue persists after performing these steps, it may be best to consult a professional mechanic or transmission specialist for further diagnosis and repair. By following these troubleshooting steps, you can identify and resolve the underlying issue causing the P0758 code