P0602

Diagnostic Chart:

CIRCUIT DESCRIPTION

The Powertrain Control Module (PCM) is the control center of the fuel injection system. It constantly looks at the information from various sensors, and controls the systems that affect vehicle performance. The PCM also performs the diagnostic function of the system. It can recognize operational problems, alert the driver through the Malfunction Indicator Lamp (MIL) (Check Engine), and store a DTC or DTC's which identify the problem areas to aid the technician in making repairs. An Electrically Erasable Programmable Read Only Memory (EEPROM) is used to house the program information and the calibrations required for engine, transmission, and powertrain diagnostics operation. The EEPROM's program can be updated by reprogramming the PCM.


CONDITIONS FOR SETTING THE DTC

The PCM is not properly programmed.


ACTION TAKEN WHEN THE DTC SETS

^ The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer.

^ A history DTC is stored.

CONDITIONS FOR CLEARING THE MIL/DTC

^ A history DTC will clear after 40 consecutive warm up cycles without a fault.

^ DTC(s) can be cleared by using a scan tool.


TEST DESCRIPTION

Number(s) below refer to the step number(s) on the Diagnostic Table.

1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored on the scan tool for later reference.

3. Refer to the latest Techline information for programming procedures.

4. Replacement PCM's must be reprogrammed. Refer to the latest Techline information for programming procedures.