Suzuki Grand Vitara JB627. Manual - part 285

7B-56 Air Conditioning System:

HVAC Control Module and Its Circuits Inspection

S6JB0B7204032

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.

HVAC control module and its circuits can be checked at HVAC control module wiring couplers by measuring voltage.

Voltage Check

1) Remove HVAC control module. Refer to “HVAC Control Module Removal and Installation in Section 7A”.
2) Connect HVAC control module and body control module couplers to HVAC control module and body control

module.

3) Check each terminal voltage with couplers connected by referring to “HVAC Control Module Voltage Table: ”.

Terminal arrangement of HVAC control module (viewed from harness side)

HVAC Control Module Voltage Table

16 15 14 13 12 11 10

32 31 30 29 28 27

23 22 21 20 19 18 17

I5JB0A720030-02

Terminal

Wire

color

Circuit

Normal value

Condition

G52-1

PPL/RED Power supply

10 – 14 V

Ignition switch turned ON.

G52-2

WHT

Electric power source
for back-up

10 – 14 V

Constantly.

G52-3

PPL/WHT

Serial communication
line of data link
connector

10 – 14 V

Ignition switch turned ON.

G52-4

RED/YEL Illumination switch

0 – 1 V

Ignition switch turned ON, lighting switch OFF
position.

10 – 14 V

Ignition switch turned ON, lighting switch ON
position.

G52-5

RED/GRN Illumination ground

0 – 1 V

Constantly.

G52-6

PNK/BLK Theft deterrent light

—

G52-8

BLK/RED

Rear defogger driving
signal

10 – 14 V

Ignition switch turned ON, rear defogger switch ON.

0 – 1 V

Ignition switch turned ON, rear defogger switch OFF.

G52-10 YEL/RED

Serial communication
line from BCM

Refer to “Inspection of BCM and Its Circuits in Section 10B”.

G52-11 PNK/GRN

Serial communication
line to BCM

Refer to “Reference waveform No. 1: ”.

G52-12

YEL

Ground for sunload
sensor

0 – 1 V

Constantly.

G52-13 BLK/RED Ground for sensors

0 – 1 V

Constantly.

G52-14 RED/WHT

Output of 5 V power
source for position
sensor of actuators

4 – 6 V

Ignition switch turned ON.

Air Conditioning System: 7B-57

G52-15 RED/BLK

Blower motor control
voltage feedback

Approx. 14 V

Ignition switch turned ON, blower speed selector
OFF.

Approx. 10 V

Ignition switch turned ON, blower speed selector 1st
position.

Approx. 9 V

Ignition switch turned ON, blower speed selector 2nd
position.

Approx. 8 V

Ignition switch turned ON, blower speed selector 3rd
position.

Approx. 6 V

Ignition switch turned ON, blower speed selector 4th
position.

Approx. 5 V

Ignition switch turned ON, blower speed selector 5th
position.

Approx. 4 V

Ignition switch turned ON, blower speed selector 6th
position.

Approx. 2 V

Ignition switch turned ON, blower speed selector 7th
position.

Less than 0.3 V

Ignition switch turned ON, blower speed selector 8th
position.

G52-16 PPL/GRN Blower motor controller

0 – 1 V

Ignition switch turned ON, blower speed selector
OFF.

Approx. 4.2 V

Ignition switch turned ON, blower speed selector 1st
– 7th position.

Approx. 8 V

Ignition switch turned ON, blower speed selector 8th
position.

G52-17

BLK

Ground for HVAC
control module

0 – 1 V

Constantly.

G52-18

PNK

Sunload sensor signal

Approx. 3 V

Ignition switch turned ON, amount of insolation is
500 W/m

Approx. 5 V

Ignition switch turned ON, amount of insolation is 0
W/m

G52-19 WHT/BLK

Evaporator
temperature sensor
signal

Approx. 3.6 V

Ignition switch turned ON, evaporator temperature 0

°C (32 °F).

Approx. 3.4 V

Ignition switch turned ON, evaporator temperature
10

°C (50 °F).

Approx. 2.4 V

Ignition switch turned ON, evaporator temperature
25

°C (77 °F).

G52-20 BLU/BLK

Inside air temperature
sensor signal

Approx. 2.4 V

Ignition switch turned ON, room temperature 25

°C

(77

°F).

Approx. 3.8 V

Ignition switch turned ON, room temperature 0

°C

(32

°F).

G52-21 WHT/RED

Temperature control
actuator position
sensor signal

Approx. 4.5 V

Ignition switch turned ON, temperature selector MAX
COOL position.

Approx. 1.5 V

Ignition switch turned ON, temperature selector MAX
HOT position.

G52-22 WHT/GRN

Air intake control
actuator position
sensor signal

Approx. 3.8 V

Ignition switch turned ON, air intake selector “REC”
position.

Approx. 1.5 V

Ignition switch turned ON, air intake selector “FRE”
position.

G52-23 WHT/BLU

Air flow control actuator
position sensor signal

Approx. 4.2V

Ignition switch turned ON, air flow selector “VENT”
position.

Approx. 3.2 V

Ignition switch turned ON, air flow selector “BI-
LEVEL” position

Approx. 2 V

Ignition switch turned ON, air flow selector “FOOT”
position.

Approx. 1.5 V

Ignition switch turned ON, air flow selector “DEF /
FOOT” position.

Approx. 0.6 V

Ignition switch turned ON, air flow selector “DEF”
position.

Terminal

Wire

color

Circuit

Normal value

Condition

7B-58 Air Conditioning System:

Reference waveform No. 1
Serial communication line to BCM (1)

A/C System Inspection at ECM

S6JB0B7204033

CAUTION

• ECM connectors are waterproofed. Each

terminal of the ECM connectors is sealed
up with the grommet. Therefore, do not
measure circuit voltage and resistance by
inserting the tester’s probe into the sealed
terminal at the harness side. Or, ECM and
its circuits may be damaged by water.

• ECM (PCM) cannot be checked by itself.

It is strictly prohibited to connect voltmeter
or ohmmeter to ECM (PCM) with couplers
disconnected from it.

Voltage Check
When checking voltage at ECM terminals related to A/C
system, refer to “Inspection of ECM and Its Circuits in
Section 1A”.

G52-27

GRY

Temperature control
actuator (COOL)

10 – 14 V

Ignition switch turned ON, temperature control
actuator is working in operation from HOT to COOL
position.

0 – 1 V

Ignition switch turned ON, except the above
condition.

G52-28 GRY/BLU

Temperature control
actuator (HOT)

10 – 14 V

Ignition switch turned ON, temperature control
actuator is working in operation from COOL to HOT
position.

0 – 1 V

Ignition switch turned ON, except the above
condition.

G52-29 GRY/RED

Air flow control actuator
(VENT)

10 – 14 V

Ignition switch turned ON, air flow control actuator is
working in operation from DEF to VENT position.

0 – 1 V

Ignition switch turned ON, except the above
condition.

G52-30 GRY/BLK

Air flow control actuator
(DEF)

10 – 14 V

Ignition switch turned ON, air flow control actuator is
working in operation from VENT to DEF position.

0 – 1 V

Ignition switch turned ON, except the above
condition.

G52-31

ORN

Air intake control
actuator (FRE)

10 – 14 V

Ignition switch turned ON, air intake control actuator
is working in operation from REC to FRE position.

0 – 1 V

Ignition switch turned ON, except the above
condition.

G52-32

GRN

Air intake control
actuator (REC)

10 – 14 V

Ignition switch turned ON, air intake control actuator
is working in operation from FRE to REC position.

0 – 1 V

Ignition switch turned ON, except the above
condition.

Terminal

Wire

color

Circuit

Normal value

Condition

Measurement terminal

CH1: “G52-11” to “G52-
17”

Oscilloscope setting

CH1: 5 V / DIV
TIME: 20 ms / DIV

Measurement condition

Ignition switch is at ON
position

I5JB0A720091-01

Air Conditioning System: 7B-59

Repair Instructions

Operation Procedure for Charging A/C with Refrigerant

S6JB0B7206001

WARNING

• Your eyes should not be exposed to refrigerant (liquid).

Any liquid Refrigerant-134a escaping by accident shows a temperature as low as approx. –6

°C (21.2

°F) below freezing point. Should liquid HFC-134a (R-134a) get into your eyes, it may cause a serious
injury. To protect your eyes against such accident, it is necessary to always wear goggles. Should it
occur that HFC-134a (R-134a) strikes your eye(s), consult a doctor immediately.
– Do not use your hand to rub the affected eye(s). Instead, use quantities of fresh cold water to

splash it over the affected area to gradually raise temperature of such area above freezing point.

– Obtain proper treatment as soon as possible from a doctor or eye specialist.

• Should the liquid refrigerant HFC-134a (R-134a) is exposed to your skin, the affected area should be

treated in the same manner as when skin is frostbitten or frozen.

• Do not handle refrigerant near any place where welding or steam cleaning is performed.
• Refrigerant should be kept in a cold and dark place. It should never be stored in any place where

temperature is high, e.g. where exposed to direct sun light, close to fire or inside vehicle (including
trunk room).

• Avoid breathing fume produced when HFC-134a (R-134a) is burned. Such fume may be hazardous to

your health.

Star

Start e

t evacuation.

acuation.

Stop e

Stop evacuation.

acuation.

20 min

20 minutes (abo

utes (above 760 mmHg)

e 760 mmHg)

Wait 10 min

ait 10 minutes

utes

Chec

Check A/C system f

k A/C system for

pressure tighteness

pressure tighteness.

Recharge A/C system with

Recharge A/C system with
refr

refriger

igerant.

ant.

Chec

Check A/C system f

k A/C system for refr

or refriger

igerant

ant

leaks and amount of refr

leaks and amount of refriger

igerant

ant

charged.

Perf

erfor

ormance test

mance test

Inspect and repair connections

Inspect and repair connections.

If gauge sho

If gauge shows

abnor

abnormal conditions

mal conditions

Recharge 570 30 g of

Recharge 570 30 g of
refr

refriger

igerant.

ant.

I5JB0A720031-02

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