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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2001 🢒 Catera 🢒 Engine 🢒 Engine Controls - 3.0L (L81) 🢒 DTC P0602

Circuit Description

This diagnostic trouble code (DTC) indicates that the engine control module (ECM) internal electrically erasable programmable read only memory (EEPROM) has not been programmed with any vehicle software, or an error occurred during the programming.

Conditions for Running the DTC

Engine cranking

Conditions for Setting the DTC

The EEPROM has not been flashed with any vehicle software, or an error occurred during the programming.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

Conditions for Clearing the MIL/DTC
    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids

This DTC may be set when a replacement ECM is installed. After programming the theft deterrent frequency code, clear the ECM DTCs using the scan tool.

Test Description

The number below refers to the step number on the diagnostic table.

  1. The engine may not start with this DTC set. If the fault is still present, the DTC will set during the cranking cycle.

DTC P0602 - Control Module Not Programmed

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check-Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

  1. Use the scan tool in order to clear the DTCs.
  2. Attempt to start the engine.

Does DTC P0602 reset?

Go to Step 3

Go to Step 7

3
  1. Reprogram the ECM with the correct theft deterrent frequency code. Refer to Engine Control Module Replacement .
  2. Use the scan tool in order to clear the DTCs.
  3. Attempt to start the engine.

Does DTC P0602 reset?

Go to Step 4

Go to Step 7

4
  1. Verify that the equipment being used is functioning properly and that all of the cable connections are clean and tight.
  2. Attempt to reprogram the ECM again with the correct theft deterrent frequency code.
  3. Use the scan tool in order to clear the DTCs.
  4. Attempt to start the engine.

Does DTC P0602 reset?

Go to Step 5

Go to Step 7

5

Important: 

   • Perform the idle learn procedure when replacing the ECM.
   • This vehicle is equipped with a theft deterrent system that interfaces with the engine control module (ECM). The ECM must also be programmed with the frequency code of the theft deterrent module that is currently on the vehicle.

Replace the ECM. Refer to Engine Control Module Replacement .

Did you complete the action?

Go to Step 6

--

6
  1. Use the scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC run and pass?

Go to Step 2

Go to Step 7

7

With a scan tool, observe the stored information, Capture Info.

Does the scan tool display any DTCs that you have not diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK