Overview:
The Fuller Advantage is equipped with a Grade Sensor which calculates vehicle incline. The grade position is used for the Hill Start Aid (HSA) feature and provides information to assist in vehicle launch and shifting. The Grade Sensor is internal to the Transmission Electronic Control Unit (TECU). Fault Code 68 indicates an issue with either the Grade Sensor or the Grade Sensor calibration.

Note: Initial calibration of the Grade Sensor must be completed at the OEM assembly plant or anytime the TECU is replaced in the field. See Grade Sensor Calibration procedure in TRSM0980.

Detection:
Starting at key on, the TECU verifies the Grade Sensor is calibrated and current grade position is within range. If the sensor is not calibrated or grade position is out of range, Fault Code 68 sets Active.

Conditions to Set Fault Code Active:
FMI 13 – Out of Calibration: Grade Sensor has not been calibrated.

Fallback:
All FMIs
• “F” flashes in gear display.
• Service light flashes (if equipped).
• Hill Start Aid activates regardless of grade. Conditions to Set Fault Code Inactive All FMIs: Grade position is within range or the Grade Sensor has been calibrated

Possible Causes:
FMI 13
1) Grade Sensor
– Incorrect or uncompleted calibration
2) TECU
– Grade Sensor incorrect or incomplete calibration
– Not securely mounted
– Internal failure