UltraShift PLUS
TRTS0940 EN-US
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November 2023 - A

Main Case Control

Overview

This symptom-driven test is performed if a single dash (-) appears in the gear display and there are no Active or Inactive fault codes. In this case, the transmission is unable to shift into neutral. This test investigates conditions within the transmission that may cause this symptom.

Detection

  • A dash “-” appears in the gear display.
  • Transmission is unable to confirm neutral.
  • Transmission will not attempt to shift.

Possible Causes

  • Vehicle Power and Ground
    • Poor power or ground supply to TECU
    • Battery failure
    • Bent, spread, corroded or loose terminals
  • X-Y Shifter
    • Internal failure
    • Gear Position Sensor failure
    • Rail Position Sensor failure
    • Bent, spread, corroded or loose terminals
  • Mechanical Transmission
    • Wear or damage to Shift Bar Housing
    • Wear to Sliding Clutch slot width
    • Wear or damage to Shift Yokes
    • Wear or damage to internal transmission components
  • Clutch
    • Clutch stuck engaged or dragging clutch

Component Identification

_Graphics/LineArt/TRTS0940_FC71-72-73-81_ID1.png

1. Transmission Electronic Control Unit (TECU)

2. 38-Way Transmission Harness Connector

3. Gear Position Sensor

4. 3-Way Gear Position Sensor Connector

5. 2-Way Gear Motor Connector (blue)

6. 2-Way Gear Motor Connector Body (blue)

_Graphics/LineArt/TRTS0940_FC71-72-73-81_ID2.png

1. X-Y Shifter

2. 2-Way Rail Motor Connector (black)

3. 2-Way Rail Motor Connector Body (black)

4. 3-Way Rail Position Sensor Connector

5. Rail Position Sensor

6. 38-Way Vehicle Harness Connector

Main Case Control Test

A
Purpose:Verify conditions to enter Main Case Control Test.

  1. Set parking brake and chock wheels.

  2. Key on with engine off.

  3. Depress and hold service brake. Use the shift device to select Neutral.

    _Graphics/LineArt/TRTS0940_FRONTBOX_Neutral.png

  4. Observe the gear display.

  • If gear display shows a solid “N,” Go to Step B

  • If gear display shows a dash (-) or a flashing gear number, Go to Step C

B
Purpose:Confirm operation of main case gearing.

  1. Set parking brake and chock wheels.

  2. Key on with engine off.

  3. Depress and hold service brake. Select Drive with the shift device.

  4. Observe the gear display.

  5. Depress and hold service brake. Use the shift device to select Neutral.

    _Graphics/LineArt/TRTS0940_FRONTBOX_Neutral-Number.png

  • If gear display showed a solid gear number and returned to neutral, test complete.

  • If gear display showed a dash (-) or a flashing gear number, Go to Step C

C
Purpose:Verify condition of power and ground supply.

  1. Perform the Electrical Pretest. Reference the Electronic Clutch Actuator (ECA) Identification Overview. Record the reading(s) from the Load Test in Step C of the Electrical Pretest in the table.

  • If Electrical Pretest fails, repair per Electrical Pretest instructions and retest vehicle operation.

  • If Electrical Pretest passes, Go to Step D

BatteryVoltage DropLoad Test Status (Pass/Fail)
1
2
3
4
5
D
Purpose:Inspect X-Y Shifter for physical damage.

  1. Key off.

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

  2. Inspect the physical condition of X-Y Shifter and all connections.

  3. Inspect Transmission Harness for any pinched, chafed, corroded or shorted wiring.

  4. Disconnect both 2-Way X-Y Gear and Rail Position Sensor Connectors.

    _Graphics/LineArt/TRTS0940_FC71-72-73-81_Connectors.png

  5. Disconnect both 2-Way X-Y Motor Connectors to the Transmission Harness.

  6. Inspect connectors for corrosion, loose terminals, bent or spread pin or damage to the connector bodies.

  • If damage to the X-Y Shifter or X-Y Shifter wiring is found, replace X-Y Shifter. Go to Step V

  • If damage to the Transmission Harness is found, replace Transmission Harness. Go to Step V

  • If no damage is found, Go to Step E

E
Purpose:Inspect condition of X-Y Shifter internal components.

  1. Key off.

  2. Remove the X-Y Shifter.

  3. Inspect condition of the X-Y Shift Finger and Cross Shaft for damage or wear.

    _Graphics/LineArt/TRTS0940_FC71-72-73-81_XYInspections.png

  4. Inspect the X-Y Shifter ball screw for signs of coolant contamination.

    For the latest Service Bulletin updates, visit Roadranger.com.

  • If coolant contamination is found, repair the vehicle coolant system leak and follow Service Bulletin TMIB0124 for complete repair procedure. X-Y Shifter must be replaced upon completion of service bulletin. Go to Step V

  • If damage to the X-Y Shifter is found, replace X-Y Shifter. Go to Step V

  • If no damage is found, Go to Step F

F
Purpose:Inspect condition of Shift Bar Housing.

  1. Key off.

  2. Inspect condition of the Shift Bar Housing Shift Blocks. Look for uneven gaps between the Shift Blocks or excessive wear to the block faces.

  3. Verify Shift Blocks are tight to the rails and there are no other mechanical issues with the Shift Bar Housing.

    _Graphics/LineArt/TRTS0940_FC71-72-73-81_ShiftBar.png

  4. Verify transmission shifts fully in and out of each gear.

  5. Test the Shift Interlock to verify that the transmission will not engage two gears at once. See the Shift Interlock Inspection Procedure Shift Interlock Inspection.

G
Purpose:Inspect condition of the internal transmission components.

  1. Key off.

  2. Drain and save the transmission oil. Inspect oil for significant metal fragments.

  3. Remove 8-bolt PTO cover.

  4. Inspect main case gears for damage or excessive movement.

  5. Inspect Shift Yokes and Sliding Clutches for damage or excessive wear.

  • If damage is found or if there are significant metal fragments in the oil, replace damaged, worn or failed transmission components. Go to Step V

  • If no damage is found within the transmission main case, Go to Step H

    Note: If unsure whether damage or wear is significant, take pictures of the transmission gearing. Ensure these pictures are clear and the components are easily visible. Email these pictures to auto.rtw@eaton.com and contact Eaton at (800) 826-4357.

H
Purpose:Collect Service Activity Report.

  1. Key off.

  2. Reconnect all connectors and verify that all components are properly installed, including X-Y Shifter.

  3. Reinstall 8-bolt PTO cover.

  4. Refill transmission with lubricant.

  5. Key on with engine off.

  6. Connect ServiceRanger.

  7. Retrieve Snapshot and VPA data by creating a Service Activity Report within ServiceRanger.

  8. Update transmission software to latest available level.

    Caution
    To avoid damaging the TECU, use an Eaton-approved communications adapter and ensure all satellite systems are disabled before updating software.

  9. Retrieve and record the transmission fault codes, and FMIs, and their occurrences and timestamps.

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 several shifts into various gears.

  • If the transmission finds neutral and shifts through the gears properly, test complete.

  • If the transmission does not find neutral or does not shift through the gears properly, contact Eaton at 800-826-4357 for further diagnostics.