P0381

DTC P0381 Wait to Start Lamp Control Circuit

Circuit Description

The glow plug lamp is located on the instrument panel (IP) cluster. The glow control system is operated when the engine coolant temperature is low which allows easier engine starting. If the ignition switch is turned ON when the engine coolant temperature is low the ECM illuminates the glow plug lamp and turns ON the glow plugs. After a fixed time passes the ECM turns OFF the glow plug lamp and the glow plugs. The ECM monitors the glow plug lamp control circuit for conditions that are incorrect for the commanded state of the glow plug lamp. For example a failure condition exists if the ECM detects low voltage when the glow plug lamp is commanded OFF or high voltage when the glow plug lamp is commanded ON. If the ECM detects an improper voltage level on the control circuit this DTC will set.

Condition for Running the DTC

^ The battery voltage is between 10 to 16 volts.
^ The ignition switch is ON.

Condition for Setting the DTC

Either of following condition is met:

^ The ECM detects a low voltage condition on the glow plug lamp control circuit when the lamp is commanded OFF.
^ The ECM detects a high voltage condition on the glow plug lamp control circuit when the lamp is commanded ON.

Action Taken When the DTC Sets

^ The ECM illuminates the MIL on the second consecutive driving cycle when the diagnostic runs and fails. Refer to DTC Type Definitions for Action Taken When the DTC Sets - Type B.

Condition for Clearing the DTC

^ Refer to DTC Type Definitions for Condition for Clearing the MIL/DTC - Type B.

Diagnostic Aids

^ If an intermittent condition is suspected refer to Intermittent Conditions in this section.

Circuit/System Testing DTC P0381