Engine Control: 1A-31
IAC System Troubleshooting
ZAJ6111104019
Wiring Diagram
Troubleshooting
For step 2
ECM
1
2
3
4
A
B
12V (From Main relay)
1
1. IAC valve
Step Action Yes No
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):
750 – 850 r/min (approx. 0 – 30%)
Is result OK?
IAC system is in good
condition.
Go to step 2.
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 Ω for each test?
Proceed to “Unstable
Idling / Trolling” in
“Troubleshooting
Without Self-Diagnostic
Code” (Page 1A-30)
and check items except
for “Faulty IAC System”.
• Faulty IAC valve.
• Poor connection.
• Open wire harness.
4A3
2B1