Circuit Description
The engine control module (ECM) enables the appropriate fuel injector pulse for each cylinder. An ignition 1 voltage is supplied to the fuel injectors. The ECM controls each fuel injector by grounding the control circuit via a solid state device called a driver.
Diagnostic Aids
| • | Performing the Fuel Injector Coil Test may help isolate an intermittent condition. Refer to Fuel Injector Solenoid Coil Test . |
| • | For an intermittent condition, refer to Intermittent Conditions . |
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connect End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | |
2 | Is DTC P0201, P0202, P0203, or P0204 set? | -- | Go to Step 3 | |
3 |
Does the test lamp illuminate? | -- | Go to Step 4 | Go to Step 11 |
4 |
Is the resistance more than the specified value? | 3 ohms | Go to Step 12 | Go to Step 5 |
5 |
Does the test lamp flash brightly for each injector? | -- | Go to Intermittent Conditions | Go to Step 6 |
6 | Does the test lamp remain illuminated at all times for any injector circuit? | -- | Go to Step 8 | Go to Step 7 |
7 | Test the control circuit of the affected fuel injector for an open and for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 9 |
8 | Test the control circuit of the affected 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 15 | Go to Step 14 |
9 |
Is the resistance more than the specified value? | 15 ohms | Go to Step 13 | Go to Step 10 |
10 | Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 14 |
11 | Repair the open in the ignition 1 voltage circuit of the fuel injectors. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 15 | -- |
12 | Repair the high resistance in the ignition 1 voltage circuit of the fuel injectors. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 15 | -- |
13 | Repair the high resistance in the control circuit of the fuel injector. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 15 | -- |
14 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | -- | Go to Step 15 | -- |
15 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2 |
