Suzuki Liana RH413, Service Manual

Page: 898 / 1302

7B-59 Air Conditioning System: Automatic Type
DTC Troubleshooting
Step Action Yes No
1 1) Check if DTC P0115 and/or P1705 are detected referring
to “DTC Check in Section 1A”.
Are DTC P0115 and/or P1705 detected?
Perform troubleshooting
by referring to “DTC
P0115 (No. 19): Engine
Coolant Temp. (ECT)
Circuit Malfunction in
Section 1A” and “DTC
P1705 (No. 51): Engine
Coolant Temperature
Signal Circuit
Malfunction in Section
5A”. After the
troubleshooting, if DTC
B1510 is still detected,
go to Step 2. Go to Step 2.
2 1) Start the engine, and then warm it up till the engine
coolant temperature rises to the normal operating
temperature (90
°
C (194
°
F) – 95
°
C (203
°
F)).
2) Check signal inputted to “YEL/GRN” wire terminal of
HVAC control module by using oscilloscope.
Is waveform as shown in figure above?
Poor connection of
“YEL/GRN” wire
terminal at HVAC
control module
connector, and/or HVAC
control module faulty. Go to Step 3.
3 1) Disconnect HVAC control module connector referring to
“HVAC Control Module Removal and Installation in
Section 7A”.
2) Disconnect ECM connectors referring to “Engine Control
Module (ECM) Removal and Installation in Section 1C”.
3) Disconnect combination meter connector referring to
“Combination Meter Removal and Installation in Section
9C”.
4) Check resistance between “YEL/GRN” wire terminal at
HVAC control module connector and “YEL/GRN” wire
terminal at ECM connectors.
Is resistance less than 1 M
Ω
?
Go to Step 4. “YEL/GRN” wire open or
high resistance.
4 1) Check resistance between “YEL/GRN” wire terminal and
body ground.
Is resistance more than 1 M
Ω
?
Poor connection of
“YEL/GRN” wire
terminal at ECM
connectors, and/or ECM
faulty. “YEL/GRN” wire shorted
to ground.
I3RH0A722012-01