U1409-IMPLAUSIBLE LEFT FRONT WHEEL SPEED SIGNAL RECEIVED

For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The messages sent on the CAN bus are distinguished by an identifier (ID). Each CAN ID is defined to contain a certain number of bytes. The Transmission Control Module (TCM) verifies that it has received the proper number of bytes for each ID.

• When Monitored:

  Continuously with the ignition on, one valid CAN ID received at least once, and no U0002-CAN Bus Off Performance DTC present.

• Set Condition:

  When the TCM detects an incorrect CAN ID from the ABS control module.

Always perform the NAG1 Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure).

1. CHECK FOR TIPM CAN BUS DTCS

• (Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Diagnosis and Testing) for diagnostic procedures and other possible causes.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure).

• Go To 2

2. CHECK IF ABS DTCS ARE PRESENT

• (Refer to 28 - DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Diagnosis and Testing) and perform the diagnostics for the DTCs in the ABS Module.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure).

• Using the schematics as a guide, check the Transmission Control Module (TCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the TCM in accordance with the Service Information.
• Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure).