U140A Implausible right front wheel speed signal

U140A code - This messages sent on the CAN bus are distinguished by an indentifier (ID). Each Can ID is defined to contain a certain number of bytes. The transmission control module (TCM) verifies that is has received the proper number of bytes for each ID.

When monitored this DTC continuously with the ignition on, one valid Can ID received at least once, and no U0002 Can bus off performance DTC present. Set codition when the TCM detecs an incorrect Can ID from the ABS control module.

Possible causes U140A code:

- TIPM can bus dtcs present 

- ABS control module DTCs present

- Transmission control module

Diagnostic test U140A code

Step 1. Check for TIPM can bus DTCs

With the scan tool, read TIPM DTCs.

Are there any TIPM can bus DTCs present ?

Yes, refer to totally integrated power (TIPM) diagnosis and testing for diagnostic procedures and other possible causes. Perform NAG1 Transmission Verification Test.

No, go to step 2.

Step 2. Check if ABS DTCs are present

With scan tool, read ABS DTCs.

Are there any ABS DTCs present ?

Yes, refer to antilock brake system (ABS) diagnosis and testing and perform the diagnostics for the DTCs in the ABS Module. Perform NAG1 Transmission Verification Test.

No, using the schematics as a guide, check the transmisssion 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.

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