Circuit Description
The powertrain control module (PCM) enables the appropriate fuel injector on the intake stroke for each cylinder. The powertrain control relay supplies a B+ voltage to each fuel injector through an in-line mini-fuse located in the UBEC. The PCM controls each fuel injector by grounding the control circuit via a solid state device called a driver. The PCM monitors the status of each driver. If the PCM detects an incorrect voltage for the commanded state of the driver, a fuel injector control DTC sets.
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 ignition is ON. |
| • | The ignition voltage is between 9-18 volts. |
Conditions for Setting the DTC
| • | The powertrain control module (PCM) detects an incorrect voltage on a fuel injector control circuit. |
| • | The condition exists for 30 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 Diagnosis . |
| • | For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections . |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step isolates the ignition 1 voltage circuit. An open or short to ground in this circuit sets all fuel injector DTCs.
-
If voltage is not available to the fuse, the condition exists with the powertrain relay or the circuits connected to it. The procedure in DTC P0685 diagnoses those circuits.
-
This step tests if a ground is constantly being applied to the fuel injector.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
Are DTCs P0201, P0202, P0203, P0204, P0205, and P0206 all set? | Go to Step 3 | Go to Step 4 | |
Test the supply side of the fuel injector fuse in the underhood bussed electrical center (UBEC) for battery voltage using a test lamp connected to ground. Did the test lamp illuminate? | Go to Step 8 | Go to DTC P0685 | |
4 |
Does the test lamp flash? | Go to Step 9 | Go to Step 5 |
Does the J 34730-405 Injector Test Lamp remain illuminated at all times? | Go to Step 7 | Go to Step 6 | |
6 | Test the control circuit of the fuel injector for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 10 |
7 | Test the control circuit of the fuel injector for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
8 | Test the ignition voltage supply circuit for an open between the UBEC and splice. Did you find and correct the condition? | 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 . Did you find and correct the condition? | Go to Step 13 | Go to Step 11 |
10 | Inspect for poor connections at the harness connector of the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals . Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
11 | Replace the fuel injector. Refer to Fuel Injector Replacement . Did you complete the replacement? | Go to Step 13 | -- |
12 | Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 13 | -- |
13 |
Does the DTC run and pass? | Go to Step 14 | Go to Step 2 |
14 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | System OK | |
