UltraShift PLUS
TRTS0940 EN-US
|
November 2023 - A

Fault Code 68: Grade Sensor

J1587: MID 130 SID 227 FMI 13, 14

J1939: SA 3 SPN 520321 FMI 13, 14

Overview

The UltraShift PLUS 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 TRSM0940.

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.

FMI 14 – Special Instructions: Grade Sensor is reporting an unrealistic vehicle incline.

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

  • Grade Sensor
    • Incorrect or uncompleted calibration
  • TECU
    • Grade Sensor incorrect or incomplete calibration
    • Not securely mounted
    • Internal failure

FMI 14

  • TECU
    • Not securely mounted
    • Internal failure

Component Identification

_Graphics/LineArt/TRTS0940_FC68_ID1.png

1. Transmission Electronic Control Unit (TECU)

Fault Code 68 Troubleshooting

A
Purpose:Check for Active or Inactive fault codes.

  1. Record the transmission fault codes, FMIs, occurrences, and timestamps from the Service Activity Report created during the Diagnostic Procedure.

B
Purpose:Verify TECU is properly mounted.

  1. Key off.

  2. Set parking brake and chock wheels.

  3. Verify TECU is properly secured and mounted on the transmission.

    _Graphics/LineArt/TRTS0940_FC68_TECU.png

  • If TECU is improperly mounted or not secure, mount or secure TECU properly. Go to Step C

  • If TECU is properly mounted and secured, Go to Step C

C
Purpose:Perform Grade Sensor calibration procedure.

  1. Key on with engine off.

  2. Connect ServiceRanger.

  3. In ServiceRanger, go to “Service Routines”.

  4. Select “Grade Sensor Calibration”.

    Notice
    Verify vehicle is parked on level ground and the suspension is fully aired (if equipped) and set to proper ride height.

  5. Run Grade Sensor Calibration.

  6. If procedure fails, perform Operator Triggered Grade Sensor Calibration Procedure per Eaton UltraShift PLUS Service Manual TRSM0940.

  7. Key off.

    Notice
    Allow 2–3 minutes for the TECU to perform a complete power-down sequence before proceeding.

  8. Key on with engine off.

  9. Connect ServiceRanger.

  10. Retrieve and record the transmission fault codes.

V
Purpose:Verify repair.

  1. Key off.

  2. Reconnect all connectors and verify that all components are properly installed.

  3. Key on with engine off.

  4. Clear fault codes using ServiceRanger.

  5. Drive vehicle and attempt to reset the code or duplicate the previous complaint.

  6. Check for fault codes using ServiceRanger.