GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2005 🢒 Isuzu MD F-Series 🢒 DTC 🢒 DTC P0201, P0202, P0203, P0204, P0205, or P0206

Circuit Description

The injector solenoid coil control circuit is a low voltage system and drives injectors. The engine control module (ECM) calculates the optimum fuel injection timing using the data sent from sensors, and energizes injector solenoid coils. The ECM also controls the fuel injection quantity based on the solenoid coil energize duration. If the injector solenoid coil circuit is open, this DTC will set, depending on which cylinder has the fault.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC P0201 Injector 1 Control Circuit
    • DTC P0202 Injector 2 Control Circuit
    • DTC P0203 Injector 3 Control Circuit
    • DTC P0204 Injector 4 Control Circuit
    • DTC P0205 Injector 5 Control Circuit
    • DTC P0206 Injector 6 Control Circuit

Conditions for Running the DTC
    • The battery voltage is between 10-16 volts.
    • The ignition switch is ON.
    • The engine is running.
    • The crankshaft position (CKP) sensor signal pulse is detected.

Conditions for Setting the DTC

The ECM detects that the injector coil control circuit is an open circuit.

Action Taken When the DTC Sets
    • The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
    • The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records.
    • The ECM closes the exhaust gas recirculation (EGR) valve and holds the EGR valve to a closed position.

Condition for Clearing the DTC
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids
    • If an intermittent condition is suspected, the following may cause an intermittent:
       - Poor connections
       - A misrouted harness
       - Rubbed through wire insulation
       - Broken wire inside the insulation
    • Inspect for the following conditions:
       - Poor connection at ECM--Inspect the harness connectors for the following conditions:
   • Backed-out terminals
   • Improper mating
   • Broken locks
   • Improperly formed or damaged terminals
   • Poor terminal to wire connection
       - Damaged harness--Inspect the wiring harness for damage. If the harness appears to be OK, observe the Engine Coolant Temperature display on the scan tool while moving the connectors and the wiring harness related to the sensor. A change in the display will indicate the location of the fault.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2
  1. Observe the failure Records 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. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 3

Go to Diagnostic Aids

3
  1. Turn OFF the ignition.
  2. Disconnect the appropriate injector harness in-line connector from the cylinder head cover case.
  3. Measure the resistance through the intermediate connector between the injector power supply circuit and the appropriate injector control circuit.

Is the resistance less than the specified range?

2 ohms

Go to Step 5

Go to Step 4

4
  1. Test the appropriate injector control circuits between the engine control module (ECM) and the in-line connector for the following conditions:
    2. • An open circuit
    • High resistance
  2. Repair the circuits, as necessary.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 10

5
  1. Remove the cylinder head cover.
  2. Inspect the upper portion of the appropriate injector and the injector harness.
  3. Repair the condition, as necessary. Refer to Cylinder Head Replacement in Engine Mechanical.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 6

6
  1. Turn OFF the ignition.
  2. Disconnect the appropriate injector terminal from the injector.
  3. Measure the resistance of the injector solenoid coil.

Is the resistance less than the specified range?

2 ohms

Go to Step 7

Go to Step 8

7
  1. Test the appropriate injector control circuits between the injector terminal and the intermediate connector for the following conditions:
    2. • An open circuit
    • High resistance
  2. Repair the circuits, as necessary.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 9

8
  1. Turn OFF the ignition.
  2. Inspect for poor connections at the intermediate connector.
  3. Repair the connections, as necessary.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 10

9
  1. Turn OFF the ignition.
  2. Disconnect the ECM.
  3. Inspect for poor connections at the harness connector of the ECM.
  4. Repair the connections, as necessary.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 11

10

Replace the appropriate injector. Refer to Fuel Injector Replacement .

Did you complete the replacement?

--

Go to Step 12

--

11

Important: The new ECM must be programmed.

Replace the ECM. Refer to Engine Control Module Programming and Setup , Engine Control Module Replacement/Restore Fuel Rate Data , and Fuel Injector Flow Rate Programming .

Did you complete the replacement?

--

Go to Step 12

--

12
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 13

13

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK