Diagnostic Instructions
DTC Descriptors
DTC 2146: Injector Positive Voltage Control Circuit Group 1
DTC 2149: Injector Positive Voltage Control Circuit Group 2
Circuit/System Description
The engine control module (ECM) supplies voltage to each fuel injector on the injector positive voltage control circuits. The ECM energizes each fuel injector by grounding the control circuit of that fuel injector. The ECM monitors the status of the injector
positive voltage control circuits and the fuel injector control circuits.
When the ECM detects a fuel injector circuit condition, the fuel injectors in the affected group will be disabled.
Conditions for Running the DTC
| • | The engine is operating. |
| • | The ECM monitors for a condition once per camshaft revolution. |
Conditions for Setting the DTC
The ECM detects an open, short to ground, or a short to voltage on the voltage supply circuit of the fuel injector.
Action Taken When the DTC Sets
DTCs P2146 and P2149 are Type A DTCs.
Conditions for Clearing the DTC
DTCs P2146 and P2149 are Type A DTCs.
Diagnostic Aids
| • | The fuel injectors are grouped into the following pairs: |
| - | DTC P2146-fuel injectors 1 and 4 |
| - | DTC P2149-fuel injectors 2 and 3 |
| • | 1 ohm of resistance on either fuel injector control circuit will cause these DTCs to set. |
| • | The vehicle will start and then stall with either DTC set. It will not start again until the key is cycled OFF, and then ON. |
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Circuit/System Verification
- Ignition ON, observe the diagnostic trouble code (DTC) information with a scan tool. DTCs P2146, or P2149 should not set.
- Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at both of the appropriate fuel injectors. Refer to diagnostic aids.
- Verify a test lamp does not illuminate between any of the fuel injector circuits and B+.
| ⇒ | If the test lamp illuminates, test the appropriate circuit for a short to ground. If the circuit tests normal, replace the ECM. |
- Ignition OFF, test for less than 1 volt on all of the fuel injector circuits.
| ⇒ | If greater than the specified range, test the circuit for a short to voltage. If the circuits test normal, replace the ECM. |
- Test for less than 1 ohm on all of the appropriate fuel injector circuits between the ECM and the harness connector of the fuel injectors.
| ⇒ | If greater than the specified range, repair the appropriate circuit for a high resistance. |
- If all circuits/connection test normal, test or replace the fuel injector.
Component Testing
- Disconnect the harness connector of the appropriate fuel injector.
Important: The DMM and test leads must be calibrated to 0 ohms in order to prevent misdiagnosis.
- Test for 0.3-0.6 ohms between the terminals of the fuel injector.
| ⇒ | If not within the specified range, replace the fuel injector. |
- Test for infinite resistance between each terminal of the fuel injector and ground.
| ⇒ | If not within the specified range, replace the fuel injector. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
Repair Verification
Ignition ON, observe the scan tool DPF soot mass parameter. The parameter should be less than 24 grams.
