P0759 Fault Code in Honda: Causes, Symptoms, and Fixes

This code indicates that Shift Solenoid B is either not operating properly or is stuck in the “OFF” position, which disrupts proper gear shifting. The Transmission Control Module (TCM) detects abnormal performance from the solenoid.

Common Causes:

1. Stuck or dirty solenoid (Shift Solenoid B)
2. Contaminated or low transmission fluid
3. Wiring or connector issues
4. Mechanical failure inside the valve body
5. Faulty Transmission Control Module (TCM) – rare

Symptoms:

1. Check Engine Light
2. Harsh, delayed, or failed shifting
3. Transmission stuck in one gear (limp mode)
4. Erratic or slipping gear engagement
5. Poor fuel economy

Fixes:

1. Check transmission fluid – flush if dirty or low
2. Inspect and clean the valve body & solenoids
3. Test and possibly replace Shift Solenoid B
4. Check wiring & connectors for corrosion or damage
5. Update or replace TCM if nothing else resolves it

Diagnostic Tips:

1. Use a scan tool with live data to check solenoid activation
2. Compare the expected gear vs actual gear in data logs
3. Use a multimeter to test the solenoid resistance
4. Typical range: 12–25 ohms, varies by manufacturer