Diagnosis & Repair
- Inspect air induction system for leaks. Repair as needed. Inspect A/C signal circuit. See the WIRING DIAGRAMS
article. Repair as needed.
- Ensure ignition if off. Access ECM. ECM is located behind glove box. Disconnect ECM harness connector E7. Turn ignition on. Using DVOM, measure voltage between individual connector terminals RSO, RSC, and ground. See Figure. Voltage should be 9-14 volts for both circuits.
- If voltage is within specification, go to step 5). If voltage is NOT within specification, turn ignition off. Disconnect IAC valve harness connector. IAC valve is located in front of throttle body at 6 o'clock position. Using ohmmeter, measure resistance between component terminals. See Fig 1.
- For resistance specifications, see IAC RESISTANCE table. If resistances measured are NOT within specification, replace IAC valve. If resistances are within specification, inspect circuits between IAC and ECM for opens or shorts. Repair as needed.
IAC RESISTANCE
| Terminals No. |
Ohms |
| 1 & 2 |
10-30 |
| 2 & 3 |
10-30 |
- Inspect operation of IAC valve. Remove valve. To inspect valve, see the SYSTEM/COMPONENT TESTS
article. Replace as needed. If valve is okay, replace ECM and retest.
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