Honda Rubicon stuck in one gear: ESP angle sensor and control motor
Share
Applies to: Honda Foreman Rubicon 500 (TRX500FA/FGA/FPA) with Electric Shift Program
Symptoms
- Stuck in one gear, often 1st or 3rd
- Gear indicator flashes a code (5 or 6 are common)
- Shifts fine cold, then quits after warming up
Why it happens
The Rubicon's Hondamatic transmission is shifted by a control motor that reads position from a swash-plate angle sensor. A loose sensor connector, a sensor out of adjustment, a worn control motor or wiring faults put it into fail-safe mode. Code 5 points to the motor; code 6 points to the angle sensor or its wiring.
How to fix it
- Read the flashing code on the gear indicator and look it up in the manual.
- Check the angle sensor connector and harness for looseness, water and corrosion.
- Check the angle sensor position and voltage against the manual.
- Test the control motor; replace if worn.
- After replacing the sensor, ECM or throttle sensor, do the initial-setting procedure in the manual.
Tools and parts
- Multimeter
- Dielectric grease
- Angle sensor or control motor
What the factory service manual covers
Hondamatic and ESP: fault code table, angle sensor test and adjustment, control motor test, initial setting procedure. The full procedure, specs and wiring diagrams are in the factory service manual for your machine.