Endurant HD
TRTS0950 EN-US
|
October 2024 - B

Fault Code 170: Front Axle Speed

J1939: SA 3 SPN 904 FMI 9, 13, 19

Overview

The Transmission Control Module (TCM) receives the vehicle’s Front Axle Speed message over the Primary Data Link. The transmission can utilize this input in the event Output Shaft Speed is unavailable.

Detection

The Transmission Control Module (TCM) monitors the Front Axle Speed message. If message is not received or invalid, the fault is set active.

Conditions to Set Fault Code Active

FMI 9 – Abnormal Update Rate: Front Axle Speed message not received for 10 seconds.

FMI 13 – Out of Calibration: Front Axle Speed message not available for 10 seconds.

FMI 19 – Received Network Data in Error: Front Axle Speed message invalid for 10 seconds.

Fallback

All FMIs:

Note: Refer to OEM for troubleshooting a failed system. Brake system fallback modes will vary.

  • Amber warning lamp on
  • No degraded performance

Conditions to Set Fault Code Inactive

All FMIs: Front Axle Speed signal received and valid for 10 seconds.

Possible Causes

All FMIs:

  • Front Axle Speed Sensor
    • Internal or circuit failure
    • Not configured or installed
  • Vehicle ECU
    • Internal failure

Fault Code 170 Troubleshooting

A
Purpose: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 170 is Inactive and there are other Active vehicle or transmission fault codes, troubleshoot all Active fault codes. Go to Step V

  • If Fault Code 170 FMI 13 is Active, refer to OEM and enable vehicle Front Axle Speed SPN 904. Go to Step V

  • If Fault Code 170 FMI 13 is Inactive, Go to Step V

  • If Fault Code 170 FMI 9 or 19 is Active or Inactive, Go to Step B

B
Purpose:Monitor Front Axle Speed signal message.

  1. Key on with engine off.

  2. Connect ServiceRanger.

  3. Go To “Data Monitor”.

  4. Select “Speed”.

  5. Select “Front axle speed”.

  6. Select all of the “-904” SPN sources.

    Note: Not all sources will indicate a value.

  7. Monitor Front axle speed and record reading in table.

  8. Compare reading(s) in table.

  • If readings are out of range, refer to OEM guidelines for repair or replacement of the Front Axle Speed signal message. Go to Step V

  • If readings are in range, no fault was found. The intermittent nature of the fault makes it likely that the problem is in the Front Axle Speed signal message. Contact OEM for further diagnostic instructions.

ParameterRangeReading(s)
904 - Front Axle Speed0 RPM
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.