Inspection Of Hvac Control Module And Its Circuit - Suzuki Liana RH413 Service Manual

Visual Inspection
Check visually the following parts and systems.
• Refrigerant ---- leakage and amount
• A/C pipe or hose ---- disconnection, looseness and deterioration
• A/C compressor drive belt ---- looseness and damage
• Battery ---- fluid level and corrosion of terminal
• Connectors of electric wire harness ---- disconnection and friction
• Fuses ---- burning
• Parts ---- installation and damage
• Other parts that can be checked visually

Inspection of HVAC Control Module and its Circuit

HVAC control module and its circuits can be checked at HVAC control module wiring couplers by measuring voltage.
CAUTION
!
HVAC control module can not be checked by itself. It is strictly prohibited to connect voltmeter to
HVAC control module with couplers disconnected from it.
Voltage Check
1) Remove HVAC control module referring to "HVAC Control Module Removal and Installation in Section 7A".
2) Check voltage at each terminal.
NOTE
As each terminal voltage is affected by the battery voltage, confirm that it is 11 V or more when ignition
switch is ON.
1
1. HVAC control module
Terminal Wire Color
G77-1 GRN/WHT A/C signal
Electric load signal for
G77-2 BLU/BLK
blower motor
G77-3 PPL/WHT Rear defogger relay
G77-4 —
G77-5 BLU/YEL Blower motor controller
Inspection item
2. HVAC control module connector "G77" (viewed from harness side)
Circuit
6.0 – 14.0 V A/C switch OFF
10.0 – 14.0 V
about 2.0 V
10.0 – 14.0 V Rear defogger switch OFF
—
about 0.0 V
2.0 – 3.0 V
Air Conditioning System: Manual Type 7B-14
Refer to "Quick Checking of Refrigerant
Charge".
Refer to "Compressor Drive Belt Inspection".
9 8
14 13 12 11 10
30 29 28 27 26 25 24 23
Normal
Voltage
0 – 1.5 V A/C switch ON
Ignition switch ON, Blower speed selector OFF, 1st or
2nd position
Ignition switch ON, Blower speed selector between
3rd and HIGH position
0 – 0.5 V Rear defogger switch ON
—
Ignition switch ON, Blower speed selector OFF
position
Ignition switch ON, Blower speed selector between
LOW and HIGH position
Correction
2
7 6 5 4 3 2 1
22 21 20 19 18 17 16 15
Condition
—
S3RH0A7214018
S3RH0A7214019
I3RH0A721004-01