U140F-IMPLAUSIBLE ENGINE VARIANT DATA

For a complete wiring diagram Refer to Section 8W.

Theory of Operation

During the initial ignition on, the Transmission Control Module (TCM) receives the calibrated data from the Engine/Powertrain Control Module (ECM/PCM) over the CAN Bus and stores this information in the EEPROM of the TCM. During normal operation the TCM compares the stored data in the EEPROM to the transmitted data from the ECM/PCM. If the calibration data does not match the DTC will set and the MIL will illuminate after two consecutive failures.

When Monitored:
Ignition on, engine running with a system voltage between 9.0 and 16.0 volts.
ECM/PCM variant data received more than twice in a row over the CAN Bus.
Set Condition:
ECM/PCM has wrong variant data installed.
ECM/PCM sending wrong or improper CAN message for more than 5.0 seconds.

Possible Causes

FCM/TIPM DTCS PRESENT

WRONG ENGINE CONTROLLER SOFTWARE

WRONG TRANSMISSION CONTROLLER SOFTWARE

ENGINE CONTROL MODULE

TRANSMISSION CONTROL MODULE

Always perform the CVT Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - CVT - STANDARD PROCEDURE)

Diagnostic Test

1. CHECK IF THE DTC IS ACTIVE

With the scan tool, read Transmission DTCs.

Is the status Active for this DTC or is the STARTS SINCE SET counter 2 or less?

Yes

Go To 2

Go To 5

2. CHECK FOR FCM/TIPM CAN BUS DTCS

With the scan tool, read FCM/TIPM DTCs.

Are there any FCM/TIPM CAN BUS DTCs present?

Yes

(Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - DIAGNOSIS AND TESTING) category and perform the appropriate symptom(s).
Perform CVT VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - CVT - STANDARD PROCEDURE)

Go To 3

3. CHECK IF THE ECM/PCM WAS REPLACED

Was the ECM/PCM replaced?

Yes

Check to make sure the right part number was used that correlates with the engine and transmission using the vehicle identification number. It may be necessary to flash the ECM/PCM to the proper configuration or replace the controller. With the scan tool perform a TCM relearn procedure.

Perform CVT VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - CVT - STANDARD PROCEDURE)

Go To 4

4. CHECK IF THE TCM WAS REPLACED

Was the TCM replaced?

Yes

Check to make sure the right part number was used that correlates with engine and transmission using the vehicle identification number. It may be necessary to flash the PCM/TCM to the proper configuration or replace the TCM with the correct configuration. With the scan tool perform a TCM relearn procedure.

Perform CVT VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - CVT - 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. Check for any Service Bulletins for possible causes that may apply. If no problems are found, replace the TCM per the Service Information.
Perform CVT VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - CVT - STANDARD PROCEDURE)

5. INTERMITTENT WIRING AND CONNECTORS

The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
Wiggle the wires while checking for shorted and open circuits.

Were there any problems found?

Yes

Repair as necessary.

Perform CVT VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - CVT - STANDARD PROCEDURE)

Test Complete.