Conditions for Clearing The MIL/DTC

The ECM will turn the MIL "OFF" on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present.
DTC P0602 can be cleared by using the Tech 2 "Clear Info" function or by disconnecting the ECM battery feed.

DTC P0602 - CONTROL MODULE PROGRAMMING ERROR

Step	Action	Values	Yes	No
1	Was the "On-Board Diagnostic (OBDII) System Check" performed?	-	Go to Step 2	Go to On-Board Diagnostic (OBD-II) System Check
2	Install the test ECM. Program the test ECM (Immobilizer system). Refer to IMMOBILIZER SYSTEM . Check the OBD-II test for following condition: When the ignition is "ON", turn on the MIL and RPL (RPL is put out after 3 seconds). When the engine is started. Did the DTC disappear?	-	Go to Step 3	Go to Step 2
3	Replace the original ECM. Check the poor connection between the ECM and ECM connector. Recheck the OBD -II test again. When the engine is started. Did the DTC disappear?	-	Verify repair	Go to Step 4
4	Disconnect the ABS control unit connector. Reprogramming the original ECM. (Engine control and Immobilizer control) Recheck the OBD -II. Did the DTC disappear?	-	Verify repair	Go to Step 5
5	Replace the ECM. Recheck the OBD -II test again. Did the DTC disappear?	-	Verify repair	Refer to Diagnostic Aids