1A-38 Engine General Information and Diagnosis:
IAC System Troubleshooting
Wiring Diagram
Troubleshooting
Step
1
1) Warm up the engine to normal operating temperature
and keep it idling.
2) Using the SDS tool, check the IAC duty cycle and idle
speed.
Idle speed (IAC duty cycle):
550 – 650 r/min (approx. 0 – 30%)
Is result OK?
2
1) Disconnect the IAC connector at the IAC valve with
ignition switch "OFF".
2) Check the resistance between following terminals.
/ IAC "1" terminal – "B" terminal
/ IAC "2" terminal – "B" terminal
/ IAC "3" terminal – "A" terminal
/ IAC "4" terminal – "A" terminal
Is the resistance 25 – 34
12V (From Main relay)
1
B
A
1. IAC valve
Action
Ω
for each test?
4 A 3
2 B 1
ECM
1
2
3
4
Yes
IAC system is in good
condition.
Proceed to "Unstable
Idling / Trolling" in
"Troubleshooting
Without Self-Diagnostic
Code" (Page 1A-37)
and check items except
for "Faulty IAC System".
For step 2
I9J011110041-01
Z9J0111104019
I9J011110036-02
No
Go to step 2.
• Faulty IAC valve.
• Poor connection.
• Open wire harness.
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