DTC P029C, P02A0, P02A4, or P02A8 — LNP or LNQ
Diagnostic Instructions
DTC Descriptors
DTC P029C: Cylinder 1 Injector Stuck Closed
DTC P02A0: Cylinder 2 Injector Stuck Closed
DTC P02A4: Cylinder 3 Injector Stuck Closed
DTC P02A8: Cylinder 4 Injector Stuck Closed
Circuit/System Description
The engine control module (ECM) supplies voltage to each fuel injector on the injector positive voltage control circuits. The ECM energises 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. The ECM detects too large negative drift on an injector. It could be an injector stuck closed for example. The injectors are separated into the following two groups:
• | Group 1 - Injectors 1 and 4 |
• | Group 2 - Injectors 2 and 3 |
When a fuel injector circuit condition is detected by the ECM, the affected fuel injector will be disabled and may disable the affected group of fuel injectors.
Conditions for Running the DTC
• | The ECM monitors for a condition once per camshaft revolution. |
Conditions for Setting the DTC
The ECM detects too large negative drift on an injector. It could be an injector stuck closed for example.
Action Taken When the DTC Sets
DTC P029C, P02A0, P02A4, P02A8 are Type B DTCs.
Conditions for Clearing the DTC
DTC P029C, P02A0, P02A4, P02A8 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Ignition ON, observe the DTC information with a scan tool. DTCs P029C, P02A0, P02A4, P02A8, P2147, P2148, P2150, P2151, P2153, P2154, P2156 or P2157 should not set.
⇒ | If any DTCs are set, refer to
DTC P2147, P2148, P2150, or P2151 : LNP or LNQ . |
- 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 the affected fuel injector.
- Ignition ON, test for 2-3 V between the low control circuit terminal 2 and ground.
⇒ | If less than the specified range, test the low control circuit for an open/high resistance or for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module. |
⇒ | If greater than the specified range, test the low control circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module. |
- Ignition ON, connect a test lamp between the affected fuel injector low control circuit terminal 1 and ground.
- Engine cranking or running, the test lamp should illuminate or flash.
⇒ | If the test lamp does not illuminate or flash, replace the K20 Engine Control Module. |
- If all circuits test normal, test or replace the affected fuel injector.
Component Testing
Static Test
- Disconnect the harness connector at the affected fuel injector.
Note: The DMM and test leads must be calibrated to 0 Ω in order to prevent misdiagnosis.
- Test for 0.2-1.5 Ω between the low control terminal 2 and the high control terminal 1.
⇒ | If not within the specified range, replace the fuel injector. |
- Test for infinite resistance between each terminal and ground.
⇒ | If not the specified value, replace the fuel injector. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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