GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2000 🢒 S/T Isuzu - 4WD 🢒 DTC 🢒 DTC P0602 Control Module Not Programmed

Circuit Description

The powertrain control module (PCM) is the control center of the fuel injection system. The PCM constantly looks at the information from the various sensors. The PCM controls the systems that affect vehicle performance. The PCM also performs the diagnostic function of the system. The PCM can recognize operational problems. The PCM can alert the driver through the malfunction indicator lamp (MIL). The PCM can store DTCs which identify the problem areas in order to aid the technician in making repairs. The PCM uses an electrically erasable programmable read only memory (EEPROM) to house the program information and the calibrations required for the engine, the transmission, and the powertrain diagnostics operation. Reprogramming the PCM can update the program of the EEPROM.

Conditions For Setting the DTC

The PCM is improperly programmed.

Action Taken When the DTC Sets
    • The malfunction indicator lamp (MIL) illuminates.
    • The PCM attempts to record the operating conditions at the time this failure is detected. However, since this is an internal PCM failure, this information may or may not be reliable. The Freeze Frame and Failure Records buffers store this information.
    • 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.
    • Use a scan tool to clear the DTCs.

Test Description

The numbers below refers to the step numbers on the diagnostic table:

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

    2.

  2. The replacement PCM must be programmed and the Crankshaft Position System Variation Learn procedure must be performed.

Step

Action

Values

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Was the PCM just replaced?

--

Go to Step 3

Go to Step 4

3

  1. Program the PCM. Refer to Powertrain Control Module Replacement/Programming .
  2. If the DTC resets, attempt to program the PCM again (3 times maximum).

Does the DTC reset?

--

Go to Step 4

Go to Step 5

4

Important:: The replacement PCM must be programmed.

  1. Turn OFF the ignition.
  2. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming .

Did you complete the replacement?

--

Go to Step 5

--

5
  1. Turn ON the ignition with the engine OFF.
  2. Use a scan tool to clear the DTCs.
  3. Turn OFF the ignition for 30 seconds.
  4. Start the engine.

Does the DTC reset?

--

Refer to Diagnostic Trouble Code (DTC) List/Type

System OK