Injector Monitoring Value Below Limit

2549-INJECTOR MONITORING VALUE BELOW LIMIT





For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the engine running.

- Set Condition:
The ECM detects a below limit error on the injector high-side control circuit.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview

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

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Component Tests and General Diagnostics

2. FUEL INJECTOR HIGH-SIDE CONTROL CIRCUIT SHORTED TO GROUND
Turn the ignition off.
Disconnect each Fuel Injector harness connector.
Disconnect the Engine Control Module (ECM) harness connector.
Measure the resistance between ground and the Fuel Injector High-Side Control circuit in each Fuel Injector harness connector.
Is the resistance above 1000 ohms for each circuit?

Yes

- Go to 3

No

- Repair the Fuel Injector High-Side Control circuit for a short to ground.
- Perform the ECM Verification Test Ver. 1. Verification Tests

3. FUEL INJECTOR LOW-SIDE CONTROL CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the Fuel Injector Low-Side Control circuit in each Fuel Injector harness connector.
Is the resistance above 1000 ohms for each circuit?

Yes

- Go to 4

No

- Repair the Fuel Injector Low-Side Control circuit for a short to ground.
- Perform the ECM Verification Test Ver. 1. Verification Tests

4. FUEL INJECTOR HIGH-SIDE CONTROL CIRCUIT SHORTED TO FUEL INJECTOR LOW-SIDE CONTROL CIRCUIT
Measure the resistance between the Fuel Injector High-Side Control circuit and the Fuel Injector Low-Side Control circuit in each Fuel Injector harness connector.
Is the resistance above 1000 ohms between the circuits in each connector?

Yes

- Go to 5

No

- Repair the Fuel Injector High-Side Control circuit for a short to the Fuel Injector Low-Side Control circuit.
- Perform the ECM Verification Test Ver. 1. Verification Tests

5. FUEL INJECTOR HIGH-SIDE CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
Measure the resistance of each Fuel Injector High-Side Control circuit between the Fuel Injector harness connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms for each circuit?

Yes

- Go to 6

No

- Repair the Fuel Injector High-Side Control circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver. 1. Verification Tests

6. 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 Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms?

Yes

- Go to 7

No

- Repair the Fuel Injector Low-Side Control circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver. 1. Verification Tests

7. FUEL INJECTOR
Measure the resistance between the terminals of each Fuel Injector.
Is the resistance approximately 185k ohms (+/- 10%) for each injector?

Yes

- Go to 8

No

- Replace Fuel Injector.
- Perform the ECM Verification Test Ver. 1. Verification Tests

8. ENGINE CONTROL MODULE (ECM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between each Fuel Injector 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.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Replace the Engine Control Module (ECM).
- Perform the ECM Verification Test Ver. 1. Verification Tests