GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2001 🢒 Blazer - 4WD - RHD 🢒 Engine 🢒 Engine Controls - 4.3L 🢒 DTC P0200

Circuit Description

The powertrain control module (PCM) enables the appropriate fuel injector on the intake stroke for each cylinder. An ignition voltage is supplied to the fuel injectors. The PCM controls each fuel injector by grounding the control circuit via a solid state device called a driver. Each driver has a fault line that the PCM monitors. If the PCM detects an incorrect voltage for the commanded state of the driver, a fuel injector control DTC sets.

Conditions for Running the DTC
    • The engine is running.
    • The ignition voltage is between 6-18 volts.

Conditions for Setting the DTC
    • The PCM detects an incorrect voltage on the fuel injector control circuit.
    • The condition exists for 5 seconds.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the 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
    • Performing the Fuel Injector Coil test may help to isolate an intermittent condition. Refer to Fuel Injector Solenoid Coil Test .
    • For an intermittent condition refer to Intermittent Conditions .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests for voltage at the fuel injector harness connector. The ECM1 fuse supplies power to the coil side of the fuel injector harness connector. If the fuse is open, a short to ground on the fuel injector B+ supply circuit is indicated.

    2.

  2. This step verifies that the PCM is able to control the fuel injector. If the test lamp blinks, then the PCM and wiring are OK.

    3.

  3. This step tests if a ground is constantly being applied to the fuel injector.

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check-Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2
  1. With a scan tool clear the DTCs.
  2. Idle the engine at the normal operating temperature.
  3. With a scan tool, monitor the misfire current counters.

Are any of the misfire current counters incrementing?

Go to Step 4

Go to Step 3

3

  1. Observe the Freeze Frame/Failure records data for this DTC.
  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 or as close to the Freeze Frame/Failure Records data that you observed.

Does the DTC fail this ignition?

Go to Step 4

Go to Diagnostic Aids

4

  1. Turn OFF the ignition.
  2. Disconnect the fuel injector harness connector. Refer to

    Engine Wiring, LH Side (Electrical)
    Object Number: 587973 Size: LF
    (1)A/C Compressor Clutch
    (2)A/C Compressor Clutch Connector
    (3)Throttle Position (TP) Sensor
    (4)Engine Coolant Temperature (ECT) Sensor Connector
    (5)Idle Air Control (IAC) Valve
    (6)Throttle Position (TP) Sensor Connector
    (7)Fuel Injector #2 (Inside Plenum)
    (8)Idle Air Control (IAC) Valve Connector
    (9)Fuel Injector Connector (C103)
    (10)Fuel Injector #4 (Inside Plenum)
    (11)G107
    (12)Distributor
    (13)S123
    (14)Fuel Injector #6 (Inside Plenum)
    (15)Engine Oil Pressure (EOP) Sensor and Fuel Pump Switch Connector
    (16)S124
    (17)Camshaft Position (CMP) Sensor
    (18)Camshaft Position (CMP) Sensor Connector
    (19)S126
    (20)Engine Oil Pressure (EOP) Sensor and Fuel Pump Switch
    (21)Knock Sensor (KS
    (22)Knock Sensor (KS) Connector
    (23)G106
    (24)Fuel Injector #5 (Inside Plenum)
    (25)Engine Coolant Temperature (ECT) Sensor
    (26)Fuel Injector #3 (Inside Plenum)
    (27)A/C High Pressure Switch Connector
    (28)Fuel Injector #1 (Inside Plenum)
    (29)A/C High Pressure Switch
    (30)A/C Compressor Clutch
    in Wiring Systems.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the B+ supply circuit of the fuel injector with a test lamp connected to a good ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 11

5

  1. Connect the J 34730-375 Fuel Injector Test Lamp between the control circuit and the B+ supply circuit of the appropriate fuel injector harness connector.
  2. Crank the engine.

Does the test lamp blink?

Go to Step 9

Go to Step 6

6

Does the test lamp remain illuminated at all times?

Go to Step 8

Go to Step 7

7

Test the control circuit of the fuel injector for an open or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 10

8

Test the control circuit of the fuel injector for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

9

Inspect for poor connections at the harness connector of the fuel injector. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 12

10

Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

11

Repair the B+ supply circuit of the fuel injector for an open or a short to ground. Refer Wiring Repairs to in Wiring Systems.

Did you complete the repair?

Go to Step 14

--

12

Replace the fuel injector. Refer to Fuel Injector Replacement .

Did you complete the replacement?

Go to Step 14

--

13

Replace the PCM. Refer to Powertrain Control Module Replacement .

Did you complete the replacement?

Go to Step 14

--

14
  1. Use the scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. 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 15

Go to Step 2

15

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