This DTC is designed to prevent a service PCM installed in a vehicle from operating without first flashing software into it.
Test continuously.
No software data is present in PCM.
| • | Fuel pump is disabled. | 
| • | Injector pulsewidth is set to 0. | 
| • | Back-up fuel is disabled. | 
| • | The PCM will illuminate the malfunction indicator lamp (MIL) when the diagnostic runs and fails. | 
| • | The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records. | 
| • | The PCM will turn the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail. | 
| • | A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail. | 
| • | A History DTC will clear after forty consecutive warm-up cycles with no failures of any emission related diagnostic test. | 
| • | Use a scan tool to clear DTCs. | 
| • | Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Clearing Diagnostic Trouble Codes in PCM Description and Operation. | 
Number(s) below refer to the step number(s) on the Diagnostic Table.
Flashing the PCM with the correct software for the vehicle.
If flashing attempt fails the PCM is faulty.
Step  | Action  | Value(s)  | Yes  | No  | 
|---|---|---|---|---|
1  | Was the Powertrain On-Board Diagnostic (OBD) System Check performed?  | --  | Go to A Powertrain On Board Diagnostic (OBD) System Check  | |
Flash the PCM with the correct software. Does DTC P0602 reset?  | --  | Go to Powertrain Control Module Diagnosis for Verify Repair  | ||
Replace the PCM. Refer to PCM Replacement/Programming . Is the replacement complete?  | --  | Go to Powertrain Control Module Diagnosis for Verify Repair  | --  |