Idle Speed/Throttle Actuator - Electronic: Testing and Inspection

Idle Speed Control (ISC) Actuator




The idle speed control actuator is the double coil type and has two coils. The two coils are driven by separate driver stages in the ECM. Depending on the pulse duty factor, the equilibrium of the magnetic forces of the two coils will result in different angles of the motor. In parallel to the throttle valve, a bypass hose line is arrange, where the idle speed actuator is inserted in.

Circuit Diagram:

Harness Inspection Procedure (Step 1 - 2):

ACTUATOR INSPECTION
1. Disconnect the connector at the idle speed control actuator.




2. Measure the resistance between terminals.

Standard value
Terminal 1 and 2 10.5 - 14 Ohms
Terminal 2 and 3 10 - 12.5 Ohms [at 20 °C (68 °F))

3. Connect the connector at the idle speed control actuator.

Troubleshooting Procedures:

TROUBLESHOOTING HINTS
Open or short circuit is observed in idle air control system when ignition switch is turned on.

Troubleshooting Procedures:

TROUBLESHOOTING HINTS
Mechanical problems are observed in the idle air control system