For 1990-2009 cars

### Circuit/System Description

The controller area network (CAN) high speed serial data buses are used to communicate information between the control modules. Typical data transmission speeds must be high enough to ensure that a required real-time response is maintained. The CAN serial data circuits also communicate directly to the data link connector (DLC). Messages are interpreted by the externally connected CANdi module which acts as a transceiver for the scan tool.

### DTC Descriptor

DTC U0073: Controller Area Network (CAN) Bus Communication

### Conditions for Running the DTCs

The ignition voltage is between 9.0 volts and 19.0 volts.

### Conditions for Setting the DTC

CAN BUS off for 5 seconds.

### Action Taken When the DTCs Sets

DTC U0073 is a Type A DTC.

### Conditions for Clearing the DTC

DTC U0073 is a Type A DTC.

### Diagnostic Aids

• | An intermittent condition is likely to be caused by a short on the CAN serial data circuits.

• | This DTC cannot be retrieved with a current status. Diagnosis is accomplished using the symptom Scan Tool Does Not Communicate with CAN Device.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.