Neon L4-2.0L DOHC (1996)
Idle Speed/Throttle Actuator - Electronic: Description and Operation
Related Trouble Codes
Idle Air Control Motor Circuits
Name of Code:
Idle Air Control (IAC) Motor Circuits
When Monitored:
At key on and battery voltage greater than 11.5 volts.
Set Condition:
The PCM senses a short to ground or battery voltage on any of the four IAC driver circuits for 2.75 seconds while the IAC motor is active.
Theory of Operation:
The idle air control motor is used by the PCM to regulate idle speed. The motor controls the amount of air allowed to bypass the throttle blade.
The PCM controls the motor using four driver circuits to position the stepper motor.
Possible Causes:
-
Driver circuit shorted to ground
-
Driver circuit shorted to battery voltage
-
Driver circuits shorted together
-
Failed PCM
-
Shorted AC motor
-
Connector terminals
-
Connector wires
Target Idle Not Reached
Name of Code:
Target Idle Not Reached
When Monitored:
With the engine idling and in Drive if automatic. There must not be a MAP sensor trouble code or a throttle position sensor trouble code.
Set Condition:
Engine idle is not within 200 rpm above or 100 rpm below target idle for 14 seconds. Three separate failures are required to set a bad trip. Two
bad trips are required to set code.
Theory of Operation:
The Idle Air Control (IAC) motor is used by the PCM to help regulate idle speed. The motor controls the amount of air allowed to bypass the
throttle blade. The PCM controls the motor using four driver circuits to position the stepper motor.
Possible Causes:
-
Driver circuit shorted to ground
-
Driver circuit shorted to battery
-
Driver circuits shorted together
-
Failed PCM
-
Shorted IAC motor
-
Carbon deposits
-
Driver circuit open
-
Connector terminals
-
Connector wires
-
Large vacuum leak
-
Throttle misadjusted (min. airflow RPM wrong)
-
Throttle not closing reliably
Vacuum Leak Found (Idle Air Control Motor Fully Seated)
Name of Code:
Vacuum Leak Found (Idle Air Control (IAC) Motor Fully Seated)
When Monitored:
With the engine running.
Set Condition:
