Suzuki 2000 Grand Vitara SQ625 Service Manual page 107

TABLE B-4 IDLE AIR CONTROL SYSTEM INSPECTION
WIRING DIAGRAM
INSPECTION
STEP
1 Check engine idle speed and IAC duty
referring to "Idle Speed/IAC Duty
Inspection" in Section 6E1.
Is idle speed/IAC duty within specification?
2 Is engine idle speed kept specified speed
even with headlights turned ON?
3 Check IAC valve referring to "IAC Valve
Inspection" in Section 6E1.
Is check result as specified?
ACTION
ENGINE DIAGNOSIS (G16 / J20 ENGINES) 6-103
YES
Go to Step 2.
System is in good condition.
Go to Step 4.
1. Throttle body
2. Idle air control
valve
3. ECM (PCM)
4. Sensed information
5. Main relay
NO
Go to Step 3.
Go to Step 3.
IAC valve malfunction,
"Bl/B", "Lg/B", "V/B",
"Gr/Bl" or "V/Y" wire
open or short or poor
coupler connection.
If all above are OK,
substitute a known-
good ECM (PCM) and
recheck.