P2148-FUEL INJECTOR GROUP 1 SUPPLY VOLTAGE CIRCUIT HIGH

For a complete wiring diagram Refer to Section 8W

When Monitored:
With the engine running.
Set Condition:
The ECM detects a short to voltage in the fuel injector circuitry.

Possible Causes

INTERMITTENT DTC

FUEL INJECTOR HIGH-SIDE CONTROL CIRCUIT SHORTED TO VOLTAGE

FUEL INJECTOR LOW-SIDE CONTROL CIRCUIT SHORTED TO VOLTAGE

FUEL INJECTOR HIGH-SIDE CONTROL CIRCUIT OPEN OR HIGH RESISTANCE

FUEL INJECTOR LOW-SIDE CONTROL CIRCUIT OPEN OR HIGH RESISTANCE

FUEL INJECTOR

ENGINE CONTROL MODULE (ECM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

Diagnostic Test

1. DTC IS ACTIVE

NOTE: This DTC can set as a result of a fault in any of the injector circuits. Be sure to check all injector circuits before replacing an injector and all injectors before replacing a module.

Ignition on, engine not running.
With the scan tool, clear DTCs in the Engine Control Module (ECM).
Attempt to start the engine and test drive the vehicle.
With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

Go To 2

Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

2. FUEL INJECTOR HIGH-SIDE CONTROL CIRCUIT SHORTED TO VOLTAGE

Turn the ignition off.
Disconnect each Fuel Injector connector.
Disconnect the ECM harness connectors.
Remove the Main Relay.
Connect a jumper wire between cavity B7 and cavity B9 of the Main Relay Connector.
Turn the ignition on.
Measure the voltage of the Fuel Injector High-Side Control circuit in any Fuel Injector harness connector.

Is there voltage present?

Yes

Repair the Fuel Injector High-Side Control circuit for a short to voltage.

Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

Go to 3

3. FUEL INJECTOR LOW-SIDE CONTROL CIRCUIT SHORTED TO VOLTAGE

NOTE: The jumper wire should still be in place.

Measure the voltage of each Fuel Injector Low-Side Control circuit.

Is there voltage present on any of the circuits?

Yes

Repair the Fuel Injector Low-Side Control circuit for a short to voltage.

Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

Go to 4

4. FUEL INJECTOR HIGH-SIDE CONTROL CIRCUIT OPEN OR HIGH RESISTANCE

Turn the ignition off.
Measure the resistance of each Fuel Injector High-Side Control circuit between the Fuel Injector harness connector and the ECM connector.

Is the resistance below 10.0 ohms for each measurement?

Yes

Go to 5

Repair the Fuel Injector High-Side Control circuit for an open circuit or high resistance.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

5. FUEL INJECTOR LOW-SIDE CONTROL CIRCUIT OPEN OR HIGH RESISTANCE

Measure the resistance of each Fuel Injector Low-Side Control circuit between the Fuel Injector harness connector and the ECM connector.

Is the resistance below 10.0 ohms for each circuit?

Yes

Go to 6

Repair the Fuel Injector Low-Side Control circuit for an open circuit or high resistance.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

6. FUEL INJECTOR

Reconnect all connectors.
Disconnect the Fuel Injector 1 harness connector.
Ignition on, engine not running.
With the scan tool, clear DTCs in the Engine Control Module (ECM).
Attempt to start the engine.
With the scan tool, select View DTCs.

NOTE: If this DTC does not reset, replace Fuel Injector 1. If the DTC sets again, repeat this test with Fuel Injector 2, Fuel Injector 3, and Fuel Injector 4.

Did this DTC reset for each disconnected Fuel Injector?

Yes

Go to 7

Replace the disconnected Fuel Injector in accordance with the Service Information.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

7. ENGINE CONTROL MODULE (ECM)

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Injectors and the Engine Control Module (ECM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes

Repair as necessary.

Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)

Replace the Engine Control Module (ECM) in accordance with the Service Information.
Perform the ECM Verification Test Ver. 1. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)