Idle Speed Actuator
IDLE SPEED CONTROL MOTORDescription
The intake air volume at idle is controlled by opening or closing the motor valve provided in the air path that bypasses the throttle valve.
Circuit Diagram
Troubleshooting Hints
1. If the stepper motor step increases to 100 to 120 steps or decreases to 0 step, check for faulty stepper motor or open circuit in the harness.
2. If the idle speed control motor is normal but the stepper motor steps are out of specification, check the following items;
- Poorly adjusted reference idle speed.
- Deposit on the throttle valve.
- Air leaking into the intake manifold through gasket gap.
- Loose EGR valve seat.
- Poor combustion in the cylinder (faulty ignition plug, ignition coil, injector, low compression pressure, etc.).
Using scan Tool
NOTE: When the vehicle is new (within initial operation of about 300 miles), the stepper motor steps may be about 30 steps more than standard.
Harness Inspection Procedure
Actuator Inspection
Operation Sound Check
1. Check for the sound of the stepper motor after the ignition is switched ON (but without starting the motor).
2. If the operation sound cannot be heard, check the stepper motor's circuit.
3. If the circuit is normal, then the problem may be the stepper motor or the engine control module.
Resistance Measurement between terminals
1. Measure the resistance between the respective terminals.
Standard value
Terminals 2 - 3 or 1: 28 - 33 ohms at 2O° C (68° F)
Terminals 5 - 4 or 6: 28 - 33 ohms at 2O° C (68° F)
Operation check
1. Apply voltage (approx. 6 volts) as follows and check whether or not stepper motor movement occurs.
- Connect the power supply terminal (+) to terminals 2 and 5 of the connector.
- Connect the power supply (-) terminal to terminals 3 and 4
- Connect the power supply (-) terminal to terminals 3 and 4
- Connect the power supply (-) terminal to terminals 3 and 6
- Connect the power supply (-) terminal to terminals 1 and 6
- Connect the power supply (-) terminal to terminals 1 and 4.