Eaton Fuller Advantage (2017) Fault Code: 35 PID: SPN: 639 FMI: 2 J1939 Communication Link: Data Erratic

Overview:
The J1939 Data Link is a Controller Area Network (CAN) communication bus. The Fuller Advantage transmission uses the J1939 Data Link to communicate with other ECUs (ABS, Engine, Body Controller, etc.). The Transmission Electronic Control Unit (TECU) sends and receives messages from other ECUs on the data link to determine when to initiate a shift, hold shifts, command engine torque to make shifts, as well as other functions. Proper operation of the J1939 Data Link is critical for shift performance. Fault Code 35 indicates an issue with communication across the J1939 Data Link.

Detection:
TECU has either lost communication or received erratic signals over the J1939 Data Link and the TECU has not detected any low battery system fault codes.

Conditions to Set Fault Code Active:
FMI 2 – Data Erratic: TECU has lost communication or has received erratic signals over the J1939 Data Link for 5 seconds or longer.

Fallback:
FMI 2
• “F” flashes in gear display.
• Service light flashes (if equipped).
• If vehicle is configured for the J1939 Start Enable feature the engine does not crank.
• If fault occurs during power up, the transmission requires the driver to manually synchronize shifts with the throttle.
• If fault occurs while driving, transmission remains in its current gear until the vehicle stops. Transmission then requires the driver to manually synchronize shifts with the throttle.

Conditions to Set Fault Code Inactive:
FMI 2: TECU receives messages across the data link for at least 10 seconds.

Possible Causes:
FMI 2
1) 38-Way Vehicle Harness Connector
– Wiring shorted to ground, shorted to power or open
– Bent, spread, or loose terminals
2) Other ECUs
– Internal failure
3) J1939 Data Link
– Wiring shorted to ground, shorted to power or open
– Bent, spread, or loose terminals
– Excessive electrical noise
– Missing or additional terminating resistors
4) TECU
– Internal failure