Endurant HD
TRTS0950 EN-US
|
September 2024 - B

Fault Code 970: Neutral Output

J1939: SA 3 SPN 604 FMI 3, 4, 5, 6, 12, 14, 31

Overview

The Transmission Control Module (TCM) is configurable to provide a Neutral Output signal to other circuits or devices on the vehicle for an application specific vehicle operation. When Neutral is selected on the Driver Interface Device and is confirmed from transmission rail position and speed sensors the TCM will provide a 12-volt hardwired output signal to an application specific vehicle circuit or device.

The TCM is equipped to receive 4 switch inputs and control 3 relay outputs that can be configured in an Input/Output (I/O) Package to support this vocational feature. The Neutral Output circuit is connected to the TCM in the 20-Way TCM Body Harness Connector. The Neutral Output circuit is installed by the OEM or body builder. Reference Input / Output Calibration of the Appendix for recommended Neutral Output circuit wiring diagrams.

Detection

The TCM monitors the hardwired Neutral Output circuit signal. If the signal is out of range, the fault is set Active.

Conditions to Set Fault Code Active

FMI 3 – Voltage Above Normal or Shorted High: Neutral Output circuit signal shorted to power for 5 seconds.

FMI 4 – Voltage Below Normal or Shorted Low: Neutral Output circuit signal shorted to ground for 5 seconds.

FMI 5 – Current Below Normal or Open Circuit: Neutral Output circuit open for 5 seconds.

FMI 6 – Current Above Normal or Grounded Circuit: Neutral Output circuit current out of range for 5 seconds.

FMI 12 – Bad Intelligent Device: TCM has detected an internal processing error.

FMI 14 – Special Instructions: The TCM detected invalid I/O Package calibration.

FMI 31 – Condition Exists: The TCM detected invalid I/O Package calibration.

Fallback

All FMIs:

  • Amber warning lamp on
  • Devices requiring Neutral Output signal may not function

Conditions to Set Fault Code Inactive

FMI 3: Neutral Output circuit not shorted to power for 10 seconds.

FMI 4: Neutral Output circuit not shorted to ground for 10 seconds.

FMI 5: Neutral Output circuit not open for 10 seconds.

FMI 6: Neutral Output circuit current in range for 10 seconds.

FMI 12: Key cycle and fault condition no longer exits.

FMI 14, 31: Valid I/O Package calibration file is configured in TCM.

Possible Causes

FMI 3, 4, 5, 6:

  • Vehicle Neutral Output device
  • Vehicle Neutral Output wiring
    • Neutral Output is configured “Enabled” in the TCM but wiring is not installed.
    • Wiring shorted to power, shorted to ground or open.

FMI 12:

  • TCM
    • Software issue
    • Internal failure

FMI 14, 31:

  • TCM
    • Invalid I/O Package calibration file configured in TCM

Fault Code 970 Troubleshooting

A
Purpose:Identify Transmission Model.

  1. Set vehicle parking brake and chock wheels.

  2. Record transmission model from Service Activity Report created during the Diagnostic Procedure.

B
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.

C
Purpose:Verify Neutral Output wiring.

  1. Key on.

  2. Connect ServiceRanger.

  3. Go To “Configurations”.

  4. Select “Options”.

  5. Record the “Neutral Output Signal” “Current Value” in table.

  • If the Neutral Output Signal Current Value indicates “Enabled” and the Neutral Output signal circuit is not installed, select “Disabled” and follow on-screen prompts. Go to Step V

  • If the Neutral Output Signal Current Value indicates “Enabled” and the Neutral Output is properly installed and wired, refer to OEM or body builder guidelines for repair or replacement of the Neutral Output signal wiring. Go to Step V

    Note: Neutral Output signal wiring is installed by the OEM or body builder, reference OEM or body builder wiring diagrams.

ParameterValue
Neutral Output Signal
D
Purpose:Check for Active or Inactive fault codes.

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

  • If Fault Code 970 FMI 3, 4, 5, 6 is Active, Go to Step E

  • If Fault Code 970 FMI 3, 4, 5, 6 is Inactive, the intermittent nature of the fault makes it likely that the problem is in the Neutral Output circuit. Go to Step F

    Note: Neutral Output circuit and wiring are installed by OEM or body builder.

  • If Fault Code 970 FMI 12 is Active, replace Transmission Control Module (TCM). Go to Step V

  • If Fault Code 970 FMI 12 is Inactive, Go to Step V

  • If Fault Code 970 FMI 14 or 31 is Active, 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 970 FMI 14 or 31 is Inactive, Go to Step V

E
Purpose:Verify Neutral Output Signal configuration with ServiceRanger.

  1. Key on.

  2. Connect ServiceRanger.

  3. Go To “Configuration”.

  4. Select “Options”.

  5. Record the “Neutral Output Signal” Current Value.

  • If "Neutral Output Signal" Current Value indicates “Disabled” and Neutral Output signal circuit is properly installed and wired, select “Enabled" and follow on-screen prompts. Go to Step V

  • If "Neutral Output Signal" Current Value indicates “Enabled” and Neutral Output signal circuit is properly installed and wired, Go to Step F

F
Purpose:Verify Input/Output Package type with ServiceRanger.

  1. Key on with engine off.

  2. Connect ServiceRanger.

  3. Go To “Configuration”.

  4. Select “Calibrations” tab.

  5. Record "I/O Package" Current Value.

  • Based on I/O package configured refer to I/O circuit schematic indicated in table. Contact OEM or body builder for repair or replacement of Neutral Output signal circuit. Go to Step V

    Note: Neutral Output circuit and wiring are installed by OEM or body builder.

Fault Code 970: Neutral Output
Package # and Description20-Way TCM Body Connector Pin(s)Component(s)
Input / Output Calibration Package 1: Neutral Output + PTO 1 + Reverse Output3Neutral Output RelayNeutral Output Fuse 2 AmpChassis Ground
Input / Output Calibration Package 24 and 27: Force Neutral + Neutral Output + Reverse Output and Hold Neutral + Neutral Output + Reverse Output
Input / Output Calibration Package 35: Reverse Output + Neutral Output
Input / Output Calibration Package 36: Neutral Output
V
Purpose:Verify repair.

  1. Key off.

  2. Reconnect all connectors and verify 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.