Fault Code 647: Rail E Aft Solenoid (A4)

J1939: SA 3 SPN 769 FMI 0, 1, 3, 4, 5, 6, 7, 8, 12, 16, 17, 18

Overview

The Mechatronic Transmission Module (MTM) is equipped with solenoids to direct pneumatic flow. The Rail E Aft Solenoid (REAS) is energized by the Transmission Control Module (TCM) to direct vehicle supplied air pressure to actuate the Rail E Sliding Clutch in the aft or rearward direction. The REAS is located in the MTM and connected to the TCM at the 74-Way Transmission Harness Connector.

Detection

The TCM monitors the REAS. If a system failure is detected, the fault is set Active.

Conditions to Set Fault Code Active

FMI 0 – Data Valid But Above Normal (Most Severe): REAS low side current is greater than commanded current.

FMI 1 – Data Valid But Below Normal (Most Severe): REAS low side current is less than commanded current.

FMI 3 – Voltage Above Normal or Shorted High: REAS shorted to power for 2 seconds.

FMI 4 – Voltage Below Normal or Shorted Low: REAS shorted to ground for 2 seconds.

FMI 5 – Current Below Normal or Open Circuit: REAS open circuit for 2 seconds.

FMI 6 – Current Above Normal or Shorted Circuit: REAS commanded on and shorted to ground.

FMI 7 – Mechanical System Not Responding: One time during an ignition cycle, Rail E Position Sensor reported uncommanded movement aft, out of High Range, and speed sensors confirmed the loss of High Range engagement.

FMI 8 – Abnormal Frequency: REAS out of normal operating frequency.

FMI 12 – Bad Intelligent Device: REAS commanded on beyond expected duty cycle.

FMI 16 – Data Valid but Above Normal (Moderately Severe): REAS commanded on for longer than expected increasing solenoid temperature.

FMI 17 – Data Valid but Below Normal (Least Severe): Rail E Position Sensor reported uncommanded movement aft, out of High Range, and speed sensors confirmed the loss of High Range engagement.

FMI 18 – Data Valid but Below Normal (Moderately Severe): REAS commanded on below expected voltage.

Fallback

FMI 0, 1, 3, 4, 5, 6, 8, 12, 18:

  • Amber warning lamp on
  • If Rail E is engaged
    • Rail E movement toward Low Range prohibited
    • Rail E engagement of High Range prohibited
  • If Rail E is not engaged
    • Rail E movement toward Low Range prohibited
    • Urge to Move prohibited
    • Non neutral modes prohibited
    • PTO Mode Prohibited
  • If vehicle is moving and no start gear available
    • Red stop lamp on

FMI 7:

  • No degraded modes

FMI 16:

  • Amber warning lamp on
    • Red stop lamp on

FMI 17:

  • Amber warning lamp on
    • Rail E movement toward Low Range prohibited

Conditions to Set Fault Code Inactive

FMI 0, 1, 6, 7, 8, 12, 16, 17, 18: Key cycle

FMI 3, 4, 5: REAS in range for 10 seconds

Possible Causes

FMI 0, 1, 3, 4, 5, 6, 8, 16, 18:

  • MTM - REAS
    • Internal failure
    • Damaged
  • MTM - Transmission Harness
    • Wiring shorted to power, shorted to ground or open
  • TCM
    • Internal failure

FMI 7, 17:

  • MTM - REAS
    • Partially stuck open
  • Internal transmission
    • Rail E Detent
    • Rail E Shift Rail
    • Rail E Synchronizer

FMI 12:

  • TCM
    • Software issue
    • Internal failure

Additional Tools

  • Endurant HD Service Manual TRSM0950
  • Eaton Breakout Box with 74-Way Eaton Diagnostic Adapter - RR1029TR
  • Digital Volt/Ohm Meter (DVOM)
  • MTM Alignment Tool (RR1086TR-1)

Component Identification

_Graphics/LineArt/TRTS0950_FC275_ComponentID.png

1. Transmission Control Module (TCM) Cover

2. Transmission Control Module (TCM)

3. 74-Way Transmission Harness Connector (MTM-side)

4. 74-Way Transmission Harness Connector (TCM-side)

5. Transmission Control Module (TCM) Seal

6. Mechatronic Transmission Module (MTM)

Fault Code 647 Troubleshooting

A
Purpose:Vent LCA and Check for active or inactive fault codes.
  1. Set vehicle parking brake and chock wheels.

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

  • If Fault Code 647 FMI 0, 1, 3, 4, 5, 6, 8, 16, 18 is Active or Inactive, Go to Step B

  • If Fault Code 647 FMI 12 is Active or Inactive, Contact Eaton Cummins Automated Transmission Technologies for further diagnostic instructions. For Help Line phone numbers, go to Contact Information. Go to Step V

  • If Fault Code 647 FMI 7, 17 is Active or Inactive, create a Service Activity Report and select "Send to Eaton". Go to Step G

B
Purpose:Verify condition of 74-Way Transmission Harness Connector.
  1. Key off.

  2. Remove the TCM from the MTM with the 20-Way TCM Vehicle Harness Connector and 20-Way TCM Body Harness Connector connected.

    _Graphics/LineArt/TRTS0950_FC511_Check74WayTCM.png
  3. Inspect the TCM side of the 74-Way Transmission Harness Connector, verify the connector is free from contamination and corrosion; the terminals are not bent, spread or loose; and there is no damage to the connector body.

  4. Inspect the TCM Seal, verify the seal is properly installed and not damaged.

C
Purpose:Identify MTM Type.
  1. Key on with engine off.

  2. Connect ServiceRanger.

  3. Go To “Configuration”.

  4. Select “Advanced”.

    Note: If “Advanced” is not indicated, TCM software is unable to determine MTM Type. Go to Step 6.

  5. Record “MTM Type” Current Value, go to Step 7.

  6. Locate MTM part information tag and record MTM Part Number (Item 1) in table.

    _Graphics/LineArt/MTM_PartNumberLocation.png
  7. Compare MTM Part Number recorded in Step 6 with MTM Part Number in table to determine MTM Type.

MTM Part Number on tag
MTM Part NumberMTM Type
A-10000715PS-393
A-10002594
A-10004202
A-10004231PS-496
A-10004356
A-10004383
D
Purpose:Verify Rail E Aft Solenoid resistance and not shorted to ground.
  1. Key off.

  2. Connect the Eaton Breakout Box with 74-Way Eaton Diagnostic Adapter to the MTM side of the 74-Way Transmission Harness Connector.

    _Graphics/LineArt/TRTS0950_FC511_74WaytoMTM.png
  3. Measure resistance at the Eaton Breakout Box between Pin 62 and Pin 63. Record reading in table.

    _Graphics/LineArt/TRTS0950_FC647_DVOM62and63ohms.png
  4. Measure resistance at the Eaton Breakout Box between Pin 63 and Ground (TCM mounting stud). Record reading in table.

    _Graphics/LineArt/TRTS0950_FC647_DVOM63andGroundohms.png
  5. Compare reading(s) in table.

  • If readings are in range, Go to Step F

  • If readings are out of range, replace Mechatronic Transmission Module (MTM). Go to Step V

    Note: MTM removal and installation requires the transmission to be removed from the vehicle. Reference Endurant HD Service Manual TRSM0950, Transmission Removal Service Procedure.

PinsRangeReading(s)
62 to 633.6–4.4 Ohms
63 to ground (TCM mounting stud)Open Circuit (OL)
E
Purpose:Verify Rail E Aft Solenoid resistance and not shorted to ground.
  1. Key off.

  2. Connect the Eaton Breakout Box with 74-Way Eaton Diagnostic Adapter to the MTM side of the 74-Way Transmission Harness Connector.

    _Graphics/LineArt/TRTS0950_FC511_74WaytoMTM.png
  3. Measure resistance at the Eaton Breakout Box between Pin 48 and Pin 49. Record reading in table.

    _Graphics/LineArt/TRTS0950_FC570_DVOM48and49ohms.png
  4. Measure resistance at the Eaton Breakout Box between Pin 48 and Ground (TCM mounting stud). Record reading in table.

    _Graphics/LineArt/TRTS0950_FC570_DVOM48andGroundohms.png
  5. Compare reading(s) in table.

  • If readings are in range, Go to Step F

  • If readings are out of range, replace Mechatronic Transmission Module (MTM). Go to Step V

    Note: MTM removal and installation requires the transmission to be removed from the vehicle. Reference Endurant HD Service Manual TRSM0950, Transmission Removal Service Procedure.

PinsRangeReading(s)
48 to 493.4–5.5 Ohms
48 to ground (TCM mounting stud)Open Circuit (OL)
F
Purpose:Check for Active or Inactive fault codes.
  1. Key off.

  2. Remove the 74-Way Eaton Diagnostic Adapter.

  3. Reinstall the TCM to the MTM.

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

  5. Key on.

  6. Connect ServiceRanger.

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

G
Purpose: Verify mechanical movement of the Rail E Synchronizer.
  1. Key off.

  2. Remove the MTM.

    Note: MTM removal and installation requires the transmission to be removed from the vehicle. Reference Endurant HD Service Manual TRSM0950, Transmission Removal and MTM Removal Service Procedures.

  3. Install the MTM Alignment Tool (RR1086TR-1) onto the main housing.

    Note: Reference Manually Actuate Rail E Procedure.

  4. Using the Rail E Lever, move Rail E to neutral (if necessary).

  5. Shift Rail E into the High Range (fore) engagement position and return to neutral.

  6. Shift Rail E into the Low Range (aft) engagement position and return to neutral.

  • If Rail E shifts between neutral, High and Low Range, Go to Step H

  • If Rail E does not shift between neutral, High or Low Range, Go to Step H

H
Purpose:Verify mechanical movement of the Rail E Range Synchronizer without detent.
  1. Remove the Rail E Detent Plug, Spring and Detent.

    Note: Reference Endurant HD Service Manual TRSM0950, Harness Bracket Service Procedure and Rear Housing Disassembly Service Procedure for Rail E Detent location and removal.

  2. Install the MTM Alignment Tool (RR1086TR-1) onto the main housing.

  3. Using the Rail E Lever, move Rail E to neutral (if necessary).

  4. Shift Rail E into the High Range (fore) engagement position and return to neutral.

  5. Shift Rail E into the Low Range (aft) engagement position and return to neutral.

  • If Rail E shifts between neutral, High and Low Range, Contact Eaton Cummins Automated Transmission Technologies for further diagnostic instructions. For Help Line phone numbers, go to Contact Information. Go to Step V

  • If Rail E does not shift between neutral, High and Low Range, Go to Step I

  • If Rail E Detent could not be removed, Go to Step I

I
Purpose:Verify mechanical condition of the Rail E Synchronizer and Shift Rail.
  1. Remove the Rear Housing.

  2. Inspect the Rail E Synchronizer, Shift Rail, Detent and Rear Housing Detent bore.

  • Contact Eaton Cummins Automated Transmission Technologies for further diagnostic instructions. For Help Line phone numbers, go to Contact Information. Go to Step V

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. Connect ServiceRanger.

  5. Go to “Fault Codes”.

  6. Select “Clear All Faults”.

  7. Operate vehicle and attempt to reset the fault code or duplicate the previous complaint.

  8. Check for fault codes using ServiceRanger.