Refer to Engine Controls Schematics
Fuel Injectors
.
Circuit Description
The Powertrain Control Module (PCM) controls the fuel injector control circuit using a multi function driver (MFD). The MFD has the ability to detect an electrical malfunction. If an electrical malfunction is detected, the MFD signals the PCM to set DTC P0203.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
| • | An incorrect voltage level is being detected on an injector driver circuit. |
| • | Above condition for over 30 seconds |
Action Taken When the DTC Sets
| • | The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed. |
| • | The PCM will store conditions which were present when the DTC set as Freeze Frame and Failure Records data. |
Conditions for Clearing the MIL/DTC
| • | The PCM will turn OFF the MIL during the third consecutive trip in which the diagnostic has been run and passed. |
| • | The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
| • | The DTC can be cleared by using the scan tool. |
Diagnostic Aids
Monitor the injector fault parameter in the scan tool. Wiggle the electrical harnesses for the effected electrical circuit. If the status changes on the scan tool, that may be an indicator where an intermittent fault may be located.
Check for the following conditions:
| • | Poor connection at the PCM--Inspect harness connectors for: |
| - | Backed out terminals |
| - | Improper mating |
| - | Broken locks |
| - | Improperly formed or damaged terminals |
| - | Poor terminal to wire connection |
| • | Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
| • | Damaged harness--Inspect the wiring harness for damage. If the harness appears to be OK, observe the display on the scan tool while moving connectors and wiring harnesses related to the circuit. Refer to Wiring Repairs in Wiring Systems. |
Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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If the scan tool indicates STUCK HIGH there is a short to battery positive voltage on the fuel injector control circuit.
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If the scan tool indicates STUCK LOW there is an open or a short to ground on the fuel injector control circuit.
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When the multiple-way connector is disconnected, other DTCs will be set. These DTCs should be disregarded.
If the scan tool indicates a STUCK HIGH while cranking, the short to battery positive voltage is between the multiple-way connector and the PCM. If the scan tool indicates STUCK LOW while cranking the short to battery positive voltage is between the multiple-way connector and the fuel injector.
Important: While cranking the engine with the multiple-way connector disconnected, all of the other injector circuits should indicate STUCK LOW, this is a fault induced by disconnecting this connector. They will resume correct operation when the connector is reconnected.
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This step is testing for a short to ground in the circuit.
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The fuel injector in this circuit will need to be tested after the short to ground is repaired or after the PCM is replaced.
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This step is testing the function of the PCM. If the test lamp flashes then the PCM is able to supply the ground.
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This vehicle is equipped with a PCM which utilizes an electronically erasable programmable read only memory (EEPROM). When the PCM is replaced, the new PCM must be programmed.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
2 | Start and idle the engine. Does the scan tool indicate this DTC failed this ignition? | -- | ||
3 |
Does the scan tool indicate this DTC failed this ignition? | -- | Go to Diagnostic Aids | |
With a scan tool, observe the Cyl. Injector Ckt. Status parameter for this injector. Does the scan tool indicate this parameter STUCK HIGH? | -- | |||
Does the scan tool indicate this parameter STUCK LOW? | -- | Go to Diagnostic Aids | ||
|
Important: : While cranking the engine with the multiple-way connector disconnected, all of the other injector circuits should indicate STUCK LOW, this is a fault induced by disconnecting this connector. They will resume correct operation when the connector is reconnected.
Does the scan tool indicate this parameter STUCK HIGH when the engine is cranking? | -- | |||
7 | Test for a short to voltage on the control circuit for this injector. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||
8 | Does the scan tool indicate this parameter STUCK LOW while cranking the engine? | -- | Go to Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Between 10-35 Degrees C (50-95 Degrees F) or Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Outside 10-35 Degrees C (50-95 Degrees F) | -- |
Does the test lamp illuminate? | -- | |||
Test for a short to ground on this injector control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the conditions? | -- | |||
Does the test lamp flash? | -- | Go to Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Between 10-35 Degrees C (50-95 Degrees F) or Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Outside 10-35 Degrees C (50-95 Degrees F) | ||
12 | Test for an open on this injector control circuit between the multiple-way connector and the PCM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||
13 | Inspect the injector control circuit for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||
|
Important: : The replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Did you complete the replacement? | -- | -- | ||
15 |
Does the DTC reset? | -- | System OK |
