Suzuki 2000 Grand Vitara SQ625 Service Manual page 604

6E2-16 ENGINE AND EMISSION CONTROL SYSTEM (H25 ENGINE)
A: Output duty select
switch terminal
B: Diagnosis switch terminal
C: Blank
D: Ground terminal
E: Test switch terminal
F: Duty output terminal
[Not using SUZUKI scan tool] (vehicle with monitor connector)
NOTE:
If ECM (PCM) parts No. ends with "0", ECM (PCM) does not out-
put IAC duty through duty output terminal in monitor coupler.
First of all, check label on ECM (PCM) for part No. if so, check
IAC duty by using Tech 1.
1) Disconnect scan tool from DLC if connected.
2) Warm up engine to normal operating temperature.
3) Stop engine and connect duty meter (3) between duty output ter-
minal and ground terminal of monitor connector (1).
4) Using service wire (2), ground diagnosis switch terminal in moni-
tor connector.
5) Set tachometer.
6) Start engine and warm it up completely.
7) Check IAC duty and idle speed. If duty and/or idle speed is out
of specifications, check idle air control system referring to Diag-
nostic Flow Table B-4 "IDLE AIR CONTROL SYSTEM CHECK"
in this section.
Engine idle speed:
IAC duty at specified
idle speed:
NOTE:
IAC duty can be checked roughly by using voltmeter. IAC
duty to voltage relation is as follows.
ON DUTY
METER INDICA-
TION (%)
0
50
100
D "OFF DUTY METER" is such duty meter that indicates
approx. 100% when terminal voltage is approx. "0 V".
D "V
" represents battery voltage while engine of vehicle
B
being checked is running.
8) Remove service wire from monitor connector.
9) Install cap to monitor connector.
10) Check that specified engine idle speed is obtained with A/C
ON if vehicle is equipped with A/C.
If not, check A/C ON signal circuit and idle air control system.
A / C OFF
750 + 50 r / min.
10 – 50% (1.4 – 7.0 V
when battery
voltage is 14 V)
OFF DUTY
METER INDICA-
TION (%)
100
50
0
A / C ON
800 + 50 r / min.
———
VOLTMETER
INDICATION
(V)
0
0.5 x V
B
V
B