Eaton Fuller Advantage (2017) Fault Code: 52 PID: 59 SPN: FMI: 7 Gear Position Sensor: Mechanical System Not Responding

Overview:
The Fuller Advantage X-Y Shifter is equipped with a Gear Position Sensor. The X-Y Gear Position Sensor reports fore-and-aft movement of the Shift Finger to the Transmission Electronic Control Unit (TECU) as a voltage signal. The X-Y Gear Position Sensor is connected to the TECU via the Transmission Harness. The TECU performs continuous diagnostics on the circuit to detect a shorted circuit, open circuit or incorrect position reading. Fault Code 52 is set when TECU has detected either an electrical failure of the X-Y Gear Position Sensor circuit or a mechanical failure within the X-Y Shifter.

Detection:
The TECU monitors both the 5-volt X-Y Gear Position Sensor supply and the return voltage signal from the X-Y Gear Position Sensor. If the system detects that either the supply voltage or return voltage is out of range, the fault code is set Active.

Conditions to Set Fault Code Active:
FMI 7 – Mechanical System Not Responding: The reported X-Y Gear Position Sensor return voltage signal is outside of the operating range physically allowed for 1 second or longer.

Fallback:
All FMIs:
• “F” flashes in gear display.
• Service light flashes (if equipped).
• Transmission remains in current gear.
• Until the fault becomes Inactive, driver may have to shut off engine with transmission in gear.

Conditions to Set Fault Code Inactive:
FMI 7: X-Y Gear Position Sensor return voltage signal returns within the physical operating range of the Shift Bar Housing.

Possible Causes:
FMI 2, 4 or 7:
1) Transmission Harness
– Bent, spread, corroded or loose terminals
– Wiring shorted to ground, shorted to power or open
2) X-Y Shifter
– Bent, spread, corroded or loose terminals
– Wiring shorted to ground, shorted to power or open
– Gear Position Sensor damaged
3) TECU
– Internal failure