- Listen for clicking sound at IAC valve immediately after engine is shut off.
NOTE:
IAC valve is located on throttle body.
- If no clicking sound is heard, check IAC valve resistance and operation. To check IAC valve resistance, ensure ignition is off. Disconnect electrical connector from IAC valve. Note IAC valve terminals. See Fig 1.
- Using ohmmeter, measure resistance between specified terminals. See IAC VALVE RESISTANCE SPECIFICATIONS table. Replace IAC valve if resistance is not within specification.
IAC VALVE RESISTANCE SPECIFICATIONS
| Terminals |
Ohms |
| B1 To S1 Or S3 |
10-30 |
| B2 To S2 Or S4 |
10-30 |
- To check IAC valve operation, remove IAC valve. Note IAC valve terminal identification. See Fig 1.
- Apply battery voltage to terminals B1 and B2. See Fig 1. Repeatedly ground terminals in sequence and ensure IAC valve closes and opens. See IAC VALVE GROUNDING SEQUENCE table. See Fig 2 and Fig 3
. Replace IAC valve if defective.
IAC VALVE GROUNDING SEQUENCE
| Application |
Terminal Grounding Sequence |
| To Close IAC Valve |
S1-S2-S3-S4-S1 |
| To Open IAC Valve |
S4-S3-S2-S1-S4 |
- If IAC valve resistance is correct and operates correctly, check wiring between Engine Control Module (ECM) and IAC valve. See wiring diagram in the WIRING DIAGRAMS
article.
- ECM is located above glove box.