Eaton Fuller Advantage (2017) Fault Code: 65 PID: SPN: 5052 FMI: 5 ECA Speed Sensor: Current Below Normal or Open Circuit

Overview:
The Fuller Advantage transmission is equipped with an Electronic Clutch Actuator (ECA) Speed Sensor that provides a secondary engine speed signal to the Transmission Electronic Control Unit (TECU). The ECA Speed Sensor is installed in the clutch housing. The ECA broadcasts the ECA Speed Sensor signal to the TECU through the High Integrity Link (HIL) contained within the transmission harness.

The TECU uses the ECA Speed Sensor signal to determine engine speed when the J1939 engine speed signal is not available. Early models have a thread-in ECA Speed Sensor installed in the flywheel housing. Fault Code 65 indicates either a loss of the signal or an electrical issue with the ECA Speed Sensor.

Detection:
The TECU monitors the ECA Speed Sensor signal and compares the sensor reading with the J1939 Engine Speed signal to determine sensor validity. The TECU also monitors the ECA Speed Sensor electrical circuit for any shorts to ground or open circuits.

Conditions to Set Fault Code Active:
The system can detect ECA Speed Sensor faults when one of the following conditions is present for 1 second or longer:
FMI 5 – Current Below Normal or Open Circuit: ECA detects an open on the ECA Speed Sensor signal circuit at key on.

Fallback:
All FMIs
• “F” flashes in gear display.
• Service light flashes (if equipped).
• No fallback mode is associated with this fault. TECU uses the vehicle engine speed signal, broadcast over J1939, to operate the transmission.

Conditions to Set Fault Code Inactive:
All FMIs: TECU detects the ECA Speed Sensor signal for 2 seconds.

Possible Causes:
FMI 5
1) ECA Speed Sensor
– Open wiring
2) Transmission Harness
– Bent, spread, corroded or loose terminals
– Wiring shorted to ground, shorted to power or open
3) ECA
– Internal failure