C1275

CIRCUIT DESCRIPTION
The UART serial data link allows information to be exchanged from module to module as needed. This is done by the Powertrain Control Module (PCM), the PCM requests and sends all the information that is transmitted on the UART line. When a scan tool is connected to the UART line it takes over for the PCM and sends and requests the needed information.

CONDITIONS FOR SETTING THE DTC
DTC C1275 can be set anytime the ignition is on and a message has not been received for 7 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ A DTC C1275 is stored
^ The Traction Control System (TCS) is disabled
^ The TRACTION OFF indicator is turned on
^ The ABS remains functional

CONDITIONS FOR CLEARING THE DTC
^ The condition for the Diagnostic Trouble Code (DTC) is no longer present and the scan tool clear DTC function is used
^ 50 ignition cycles have passed with no DTCs detected

DIAGNOSTIC AIDS
^ Thoroughly inspect the wiring and the connectors. Failure to carefully and fully inspect the wiring and the connectors can result in misdiagnosis. Misdiagnosis may cause replacement of parts without repairing the malfunction.
^ If an intermittent malfunction exists, refer to Troubleshooting Procedures.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
5. This step checks for a short to ground.
7. This step checks for an open in CKT 800.
11. This step checks for a short to voltage.