Suzuki Liana RH413, Service Manual

Page: 159 / 1302

Engine General Information and Diagnosis: 1A-108
Inspection of ECM and Its Circuits
S3RH0A1104064
ECM and its circuits can be checked at ECM wiring
couplers by measuring voltage, pulse signal and
resistance.
CAUTION
!
ECM cannot be checked by itself. It is strictly
prohibited to connect voltmeter or ohmmeter
to ECM with coupler disconnected from it.
Voltage Check
1) Remove ECM (1) from vehicle body referring to
“Engine Control Module (ECM) Removal and
Installation in Section 1C”.
2) Check voltage and/or pulse signal at each terminal
of couplers (2) connected, using voltmeter (3) and
oscilloscope (4).
NOTE
• As each terminal voltage is affected by the
battery voltage, confirm that it is 11 V or
more when ignition switch is turned ON.
• Voltage with asterisk (*) cannot be
measured by voltmeter because it is pulse
signal.
Check it with oscilloscope if necessary.
Viewed from harness side
I3RH0A110026-01
C41 (31P) G04 (24P) G03 (17P)
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 31
5 6 1 2 3 4 5 6 7
11 12 9 10 11 13 12 14 15 16
16 17
1 2
7 8
13 14
3 4
9 10
15
17 18
8
19 20 21 22 23 24
2
1
I2RH0B110074-01
Terminal No. Circuit Normal Voltage Condition
C41-1 Ground Below 0.3 V Ignition switch turned ON
C41-2 Ground Below 0.3 V Ignition switch turned ON
C41-3 Ground Below 0.3 V Ignition switch turned ON
C41-4 EVAP canister purge valve
10 – 14 V Ignition switch turned ON with engine stop
*0 – 0.6 V
↑↓
10 – 14 V
(Reference waveform
No.22)
Engine running and vehicle running over
40 km/h, 25 ml/h (Output signal is 10 Hz
duty pulse. Duty ratio varies depending on
vehicle condition.)
C41-5
Power steering pressure switch
(if equipped)
10 – 14 V Ignition switch ON
0 – 1.5 V
With engine running at idle, turning
steering wheel to the right or left as far as it
stops, repeating it a few times