P0758 — Shift Solenoid B Electrical

What P0758 means

P0758 is the standardized powertrain DTC for “Shift Solenoid B Electrical.” The code identifies the monitored condition; it does not by itself prove which part failed.

Possible symptoms

• Harsh, delayed, or missing shifts
• Limp mode
• Transmission warning
• Possible slipping or flare

Causes to test

These are diagnostic possibilities, not a statistical parts-replacement ranking. Vehicle-specific service information takes priority.

• Solenoid electrical fault
• Valve-body sticking or hydraulic contamination
• Harness/connector issue
• Low/incorrect fluid or pressure problem
• TCM driver/control issue

Step-by-step diagnostic workflow

1. Retrieve all TCM codes and freeze-frame data.
2. Check transmission fluid level/condition with the correct temperature/procedure.
3. Test solenoid circuit integrity and connector condition using OEM specifications.
4. Use bidirectional control/pressure data when supported.
5. Distinguish an electrical code from a hydraulic performance/stuck code before replacing parts.
6. Clear codes only after repair, then complete an appropriate drive cycle and verify the code and symptoms do not return.

Scan data worth checking

• Solenoid command/duty
• Commanded gear
• Input/output speed
• Transmission fluid temperature
• Line/pressure-control data

Severity and drivability

Moderate to high. Solenoid/control faults can cause limp mode, harsh shifts, slipping, or excess heat.

Stop driving and investigate immediately if there is a flashing MIL, oil-pressure warning, overheating, fuel leakage, severe misfire, major loss of power, abnormal mechanical noise, or a transmission that is slipping badly.

Common diagnostic mistakes

• Replacing a solenoid for a hydraulic performance code without valve-body diagnosis
• Ignoring connector fluid intrusion or harness damage
• Clearing TCM adaptations without following relearn procedures

Related generic codes