U1064

DTC U1OO1-U1254

Circuit Description
The powertrain interface module (PIM) receives information from the powertrain control module (PCM) on the class 2 serial data circuit. If there is a problem with this circuit or the PCM is not communicating, the PIM will detect this lack of information and will set a DTC. Also, if there is a problem with the serial data circuit, performing the Powertrain (OBD) System Check will lead you to the Data Link Connector Diagnosis.


Conditions for Running the DTC
- The ignition switch is ON.
- The ignition voltage is between 5-17 volts.


Conditions for Setting the DTC
- The PIM does not receive any serial data communication from the PCM for greater than 5 seconds.

Action Taken When the DTC Sets
- The PIM will display the DTC only when current.
- The Check Powertrain MIL will not be activated.

Conditions for Clearing the DTC
- A Last Test Failed (current DTC) clears, after the ignition has been cycled and the PIM receives serial data from the PCM.
- Use Tech 2 to clear the DTC.

Diagnostic Aids
The following problems may cause this DTC to set:
- Poor connections/terminal tension at the PCM.
- Poor connections/terminal tension at the PIM.

DTC U1001 - U1254 (1 Of 2):

DTC U1001 - U1254 (2 Of 2):

Test Description
The number below reters to the step number on the diagnostic table.

6. The module which was not communicating on the class 2 serial data circuit may have set Loss of Communication DTCs for those modules that it was monitoring.