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DTC P0383 or P0384 — LNP or LNQ

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0383 00: Glow Plug Control Module Control Circuit Low Voltage

DTC P0384 00: Glow Plug Control Module Control Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

B+

-

P0383 00

-

-

Ignition

P0383 00

P0383 00

-

-

Control

P0383 00

P0383 00

P0384 00

-

Ground

-

P0383 00

-

-

Circuit/System Description

The glow plug controller is a solid state device which operates the glow plugs. The temperature and the power consumption is controlled between the engine control module (ECM) and the glow plug controller within a wide range to suit the engines pre-heating requirements. The ECM controls the glow plug module with a pulse-width modulated (PWM) control circuit. The glow plug initial ON time will vary based on the system voltage and temperature. Lower temperatures cause longer ON times.

Conditions for Running the DTC
    • The ignition is ON.
    • The ignition voltage is between 9-16 V.
    • The DTCs run once per ignition cycle when the above conditions are met.

Conditions for Setting the DTC

The ECM detects an open, short to ground, or a short to voltage on the glow plug module control circuit for greater than 0.5 s.

Action Taken When the DTC Sets

DTC P0383 00 and P0384 00 are Type C DTCs.

Conditions for Clearing the DTC

DTC P0383 00 and P0384 00 are Type C DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Ignition ON, observe the DTC information with a scan tool. DTC P0383 00 or P0384 00 should not be set.
  2. 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 you observed from the freeze frame/failure records data.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector X1 at the K34 Glow Plug Control Module.
  2. Test for less than 5 Ω between the ground circuit terminal 3 and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the B+ circuit terminal 5 and ground.
    4. ⇒If the test lamp is OFF, test the B+ circuit for a short to ground or an open/high resistance.
  4. Ignition ON, connect a test lamp between the ignition circuit terminal 4 and ground.
    5. ⇒If the test lamp is OFF, test the ignition circuit for a short to ground or an open/high resistance.
  5. Test for 10-11 V between the control circuit terminal 1 and ground.
    6. ⇒If greater than the specified range, test the control circuit for a short to voltage.
    ⇒If less than the specified range, test the control circuit for a short to ground or an open/high resistance.
  6. If the circuit tests normal, replace the K34 Glow Plug Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Glow Plug Controller Replacement
    • Control Module References for ECM replacement, setup, and programming
   


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