Corolla & Tercel

1. Start engine and warm engine to normal operating temperature. Ensure idle speed is within specification. See IDLE SPEED & MIXTURE in appropriate D - ADJUSTMENTS article.
2. Turn ignition off. Apply parking brake and place transaxle in Neutral. Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 on DLC-1. See Fig 13 and Fig 14 . DLC-1 is located at driver's side of engine compartment, near strut tower.
3. Start engine and note engine RPM. After engine RPM is kept at 900-1300 RPM for 5 seconds, ensure engine returns to idle speed. If engine speed is not as specified, test IAC valve operation. If engine speed is as specified, remove jumper wire. Turn ignition off.
4. To test IAC valve operation, remove IAC valve from throttle body. See appropriate N - REMOVE/INSTALL/OVERHAUL article. Check that valve on inside of IAC valve is half open. See Fig 15. Reinstall electrical connector on IAC valve.
5. Disconnect electrical connector from Engine Coolant Temperature (ECT) sensor. See ENGINE COOLANT TEMPERATURE (ECT) SENSOR LOCATION  table.
   ENGINE COOLANT TEMPERATURE (ECT) SENSOR LOCATION
   
   

   Model	Location
   Corolla	On Flywheel End Of Cylinder Head Below Ignition Coil & Contains Dark Gray 2-Pin Electrical Connector With White & Brown Wires
   Tercel	On Coolant Housing At Flywheel End Of Cylinder Head & Contains Dark Gray 2-Pin Electrical Connector With Black/Red & Brown Wires

6. Turn ignition on. Check that valve on inside of IAC valve moves. Repeatedly disconnect and reconnect electrical connector for IAC valve several times while checking that valve on inside of IAC valve opens and closes. See Fig 15.
7. Turn ignition off. Reinstall electrical connector on ECT sensor. Remove jumper wire.
8. If IAC valve operates, wiring circuit, Engine Control Module (ECM) and IAC valve are okay. If IAC valve does not operate, check wiring circuit between the ECM and the IAC valve. Refer to the ECM LOCATION (TABLE 3)  table. See appropriate wiring diagram in L - WIRING DIAGRAMS article. If wiring circuit and ECM are okay, replace IAC valve.

Model	Location
Camry	Behind Glove Box
Celica	Below Passenger's Side Of Instrument Panel, Underneath Carpet Near Center Console
Corolla	Behind Stereo On Instrument Panel, Just In Front Of Center Console
RAV4	Behind Instrument Panel, Near Front Of Center Console
Tacoma & Tercel	Behind Glove Box
T100	Behind Passenger's Side Kick Panel
4Runner	Behind Glove Box