Suzuki GRAND VITARA XL-7 Owner's Manual page 283

6-1-122 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Step
3 Check IAC valve referring to "IAC VALVE
INSPECTION" in Section 6E2.
Is check result as specified?
4 Was idle speed within specification in
Step 1?
5 Was idle speed higher than specification
in Step 1?
6 Check A/C (input) signal circuit referring
to Step 1 of "Table B-5". (A/C signal can
be also checked by using SUZUKI scan
tool.)
Is it in good condition?
7 Was IAC duty less than about 2% in Step
1 of this table?
8 Check transmission range switch signal
referring to "INSPECTION OF ECM
(PCM) AND ITS CIRCUIT" in this section.
Is check result satisfactory?
9 Was IAC duty more than about 30% in
Step 1 of this table?
Action Yes
Go to Step 4.
Check for following :
FIA valve, Vacuum leaks, air inhal-
ing, EVAP canister purge control
system, accessory engine load,
stuck of PCV valve, clog of idle air
passage, MAF sensor, TP sensor,
ECT sensor, EGR valve malfunc-
tion (leakage from valve seat), A/C
signal, transmission range switch
signal and power steering switch
signal.
Go to Step 6.
Go to Step 7.
Check FIA valve.
Check abnormal air inhaling from
intake manifold, throttle body, PCV
valve and EVAP canister purge
control system.
Go to Step 9.
Check parts or system which can
cause engine low idle.
Check FIA valve.
Air inhaling from between throttle
body and MAF sensor, EGR valve
malfunction (leakage from valve
seat), accessory engine load, clog
of idle air passage and etc.
No
IAC valve malfunction, "BLU/
BLK", "LT GRN/BLK", "PPL/
BLK", "GRY/BLU" or "PPL/
YEL" wire open or short or
poor coupler connection.
If all above are OK, substi-
tute a known-good ECM
(PCM) and recheck.
Go to Step 5.
Go to Step 8.
A/C signal circuit open or
short, or A/C system mal-
function.
Check TP sensor (closed
throttle position) and ECT
sensor for performance.
If sensors are OK, substitute
a known-good ECM (PCM)
and recheck.
Transmission range switch
malfunction or its circuits
open or short.
Substitute a known-good
ECM (PCM) and recheck.