P256D

DTC P2560 Engine Idle Speed Selector Sensor High Voltage

Circuit Description

The idle speed selector sensor controls the idle speed during warm up and it is installed in the driver's side instrument panel. This sensor is active only when the gear position is in the neutral position (parking or neutral position for automatic transmission vehicle). When the shift lever is moved to another position the signal is ignored. The ECM receives the idle up signal from the idle speed selector sensor and controls the fuel injection quantity. The idle speed selector sensor has following circuits

^ 5 volts reference circuit
^ Low reference circuit
^ Idle speed selector sensor signal circuit

The idle speed selector sensor provides a signal to the ECM on the signal circuit which is relative to the position changes of the idle speed selector sensor angle. If the ECM detects an excessively high signal voltage this DTC will set.

Condition for Running the DTC

^ DTCs P0642 and P0643 are not set.
^ The battery voltage is between 10 to 16 volts.
^ The ignition switch is ON.

Condition for Setting the DTC

^ The ECM detects that the idle speed selector sensor signal voltage is more than 4.8 volts for 1 second.

Action Taken When the DTC Sets

^ The ECM illuminates the SVS lamp when the diagnostic runs and fails. Refer to DTC Type Definitions for Action Taken When the DTC Sets - Type C.

Condition for Clearing the DTC

^ Refer to DTC Type Definitions for Condition for Clearing the SVS Lamp DTC - Type C.

Diagnostic Aids

^ If an intermittent condition is suspected refer to Intermittent Conditions in this section.
^ Idle speed selector sensor may have an intermittent open somewhere in the operating range.

Circuit/System Testing DTC P256D