Contents Wiring diagrams Section: Automatic HVAC System All sections

Air Conditioning System: Other Suzuki Aerio I

Automatic HVAC System 26 illustrations ~2577 words

A/C System Caution

CAUTIONThe air conditioning system of this vehicle uses refrigerant HFC-134a (R-134a). None of refrigerant, compressor oil and component parts is interchangeable between two types of A/C system: one using refrigerant HFC-134a (R-134a) and the other using refrigerant CFC-12 (R-12). Be sure to check which refrigerant is used before any service work including inspection and maintenance. For identification between these two types, refer to REFRIGERANT TYPE CONSTRUCTION: MANUAL TYPE . When replenishing or changing refrigerant and compressor oil and when replacing parts, make sure that the material or the part to be used is appropriate to the A/C system installed in the vehicle being serviced. Use of incorrect one will result in leakage of refrigerant, damage in parts or other faulty condition.

Precaution for Charging

The refrigerant charge must be performed according to OPERATION PROCEDURE FOR REFRIGERANT CHARGING: MANUAL TYPE . Also, the check of refrigerant amount must be performed according to Quick Checking of Refrigerant Charge: Manual Type or A/C SYSTEM PERFORMANCE INSPECTION: MANUAL TYPE .

Because, in the sub-cool system, the point at which bubbles disappear is in insufficient charged region, the amount of refrigerant will be insufficient if the refrigerant charge is stopped at the point at which bubbles disappear. Also, overcharge causes poor performance of the A/C system and poor fuel consumption.

Scheme 130

Scheme 130: Precaution for Charging

Precautions on Servicing A/C System

WARNINGWhen refrigerant HFC-134a (R-134a) strike your eye(s), consult a doctor immediately. Do not use your hand to rub affected eye(s). Instead, use quantities of fresh cold water to splash it over affected area to thus gradually raise its temperature above the freezing point. Obtain proper treatment as soon as possible from a doctor or eye specialist. Should liquid refrigerant HFC-134a (R-134a) get on your skin, such affected part should be treated in the same manner as when skin is frostbitten or frozen.

Handling Refrigerant HFC-134a (R-134a)

  1. Always wear goggles to protect your eyes.
  2. Avoid you direct contact to liquid refrigerant.
  3. Do not heat refrigerant container higher than 40°C (104°F).
  4. Do not discharge refrigerant into atmosphere.
  5. Do not allow liquid refrigerant to touch bright metals. Refrigerant combined with moisture is corrosive and will tarnish surfaces of bright metals including chrome.

Refrigerant Line

Oil 99000-27080

Scheme 131

Scheme 131: Refrigerant Line
  1. Never use heat for bending pipes. When bending a pipe, try to make its bending radius as slight as possible.
  2. Keep internal parts of air conditioning free from moisture and dirt. When disconnecting any line from system, install a blind plug or cap to the fitting immediately.
  3. When connecting hoses and pipes, apply a few drops of compressor oil (refrigerant oil) to seats of coupling nuts and O-ring.
  4. Never reuse O-rings. Always use new one.
  5. When tightening or loosening a fitting, use two wrenches, one for turning and the other for support.
  6. Tighten flared nut and bolt to the following specified torque. Tightening torque Flared nut: 13 N.m (1.3 kg-m, 9.5 lb-ft) Bolt: 10 N.m (1.0 kg-m, 7.5 lb-ft)
  7. Route drain hose so that drained water does not make any contact to vehicle components.
  8. If pipes or hoses are replaced, replenish specified amount of compressor oil to compressor suction side by referring to «OPERATION PROCEDURE FOR REFRIGERANT CHARGING: MANUAL TYPE»(ref-251094-S01938675342007032000000) .

A/C Evaporator Inlet Air Temperature Sensor and A/C Evaporator Outlet Air Temperature Sensor Construction

These sensors send the signals of the A/C evaporator inlet and outlet air temperature to ECM, And, ECM controls the A/C operation as follows.

  1. ECM calculates the A/C ON/OFF operation temperature by comparing the A/C evaporator inlet air temperature with the A/C evaporator outlet air temperature. And, ECM controls A/C ON/OFF using the A/C ON/OFF operation temperature.
  2. In DEF/FOOT or DEF air flow mode, ECM turns off the A/C operation by detecting the A/C evaporator outlet temperature at less than 3.5°C (38.3°F). (The A/C operation come back at more than 5°C (41.0°F)

Refrigerant Type Construction

Whether the A/C in the vehicle being serviced uses HFC-134a (R-134a) or CFC-12 (R-12) is indicated on compressor label (1). Also, it can be checked by the shape of the service (charge) valve (2).

Scheme 132

Scheme 132: Refrigerant Type Construction

Sub-Cool System Description

In the sub-cool A/C system (condenser integrated with receiver / dryer), the inside of the condenser is divided into the condensation part and the sub-cooler part, and the receiver / dryer is located between those. In the receiver / dryer, the refrigerant is separated into the vapor refrigerant and the liquid refrigerant. Only the liquid refrigerant is delivered to the sub-cooler part of the condenser. The refrigerant is supercooled by the sub-cooler part of the condenser.

Scheme 133

Scheme 133: Sub-Cool System Description

On-Board Diagnostic System Description

Refer to ON-BOARD DIAGNOSTIC SYSTEM DESCRIPTION .

Scheme 134

Scheme 134: Major Components of A/C System

Scheme 135

Scheme 135: A/C System Wiring Diagram

High pressure gauge

ConditionPossible CauseCorrection
Pressure is higher than acceptable range ("A" area)Refrigerant overchargedRecharge.
Expansion valve frozen or cloggedCheck expansion valve.
Clogged refrigerant passage of high sideClean or replace.
Radiator or condenser cooling fan malfunction (Insufficient cooling of condenser)Check radiator or condenser cooling fan.
Dirty or bent condenser fins (Insufficient cooling of condenser)Clean or repair.
Compressor malfunction (Insufficient oil etc.)Check compressor.
Engine overheatCheck engine cooling system referring to ENGINE COOLING SYSTEM INSPECTION AND CLEANING .
Pressure is lower than acceptable range ("B" area)Insufficient refrigerant (Insufficient charge or leakage)Check for leakage, repair if necessary and recharge.
Expansion valve malfunction (valve opens too wide)Check expansion valve.
Compressor malfunction (Insufficient compression)Check compressor.

PRESSURE DIAGNOSTIC CHART (HIGH PRESSURE GAUGE)

Low pressure gauge

ConditionPossible CauseCorrection
Pressure is higher than acceptable range ("C" area)Expansion valve malfunction (valve opens too wide)Check expansion valve.
Compressor malfunction (Insufficient compression)Check compressor.
Pressure is lower than acceptable range ("D" area)Insufficient refrigerant (Insufficient charge or leakage)Check for leakage, repair if necessary and recharge.
Expansion valve malfunction (valve opens too narrow)Check expansion valve.
Clogged refrigerant passage (crashed pipe)Repair or replace.

PRESSURE DIAGNOSTIC CHART (LOW PRESSURE GAUGE)

Scheme 136

Scheme 136
  1. 9 Check for crossing point of center ventilation louver air temperature and recirculation air inlet temperature if it is within shaded range of graph. For example, if inlet temperature is 25°C (77°F) and center ventilation louver temperature is 8°C (46°F), their crossing point is within acceptable range as shown in graph. If crossing point is out of acceptable range, diagnose trouble referring to the following table.

Crossing point of center ventilation louver temperature and recirculation air inlet temperature

ConditionPossible CauseCorrection
Crossing point is higher than acceptable range ("E" area)Insufficient or excessive charge of refrigerantCheck refrigerant pressure.
Dirty or bent A/C evaporator finsClean or repair.
Air leakage from cooling (heater) unit or air ductRepair or replace.
Malfunctioning, switch over function of door in cooling (heater) unitRepair or replace.
Compressor malfunctionCheck compressor.
Crossing point is lower than acceptable range ("F" area)Insufficient air volume from center duct (Heater blower malfunction)Check blower motor and fan.
Compressor malfunctionCheck compressor.

A/C SYSTEM PROBLEM DIAGNOSTIC CHART

Note. If ambient temperature is approximately 30°C (86°F), it is possible to diagnose A/C system in detail referring to the following table.

ConditionPossible CauseCorrection
MANIFOLD GAUGE MPa (kg/cm 2 ) (psi)Detail
LoHi
0.23 - 0.35 (2.3 - 3.5) (33 - 50)1.4 - 1.75 (14 - 17.5) (199 - 249)Normal condition
Negative pressure0.5 - 0.6 (5 - 6) (71 - 85)The low pressure side reads a negative pressure, and the high pressure side reads an extremely low pressure. Presence of frost around tubing to and from receiver / dryer and expansion valve.Dust particles or water droplets are either stuck or frozen inside expansion valve, preventing the refrigerant from flowingClean expansion valve. Replace it if it cannot be cleaned. Replace receiver / dryer. Evacuate the A/C system and recharge with fresh refrigerant.
Normal: 0.23 - 0.35 (2.3 - 3.5) (33 - 50) Abnormal: Negative pressureNormal: 1.4 - 1.75 (14 - 17.5) (199 - 249) Abnormal: 0.7 - 1.0 (7 - 10) (100 - 142)During A/C operation, the low pressure side sometimes indicates negative pressure, and sometimes normal pressure. Also high pressure side reading fluctuates between the abnormal and normal pressure.Expansion valve is frozen due to moisture in the system, and temporarily shuts off the refrigeration cycle.Replace expansion valve. Replace receiver / dryer. Evacuate A/C system and recharge with fresh refrigerant.
0.05 - 0.15 (0.5 - 1.5) (7 - 21)0.7 - 1.0 (7 - 10) (100 - 142)Both low and high pressure sides indicate low readings. Continuous air bubbles are visible through sight glass. Output air is slightly cold.Insufficient refrigerant in system (Refrigerant leaking).Using leak detector, check for leaks and repair as necessary. Recharge refrigerant to a specified amount. If the pressure reading is almost 0 when the manifold gauges are attached, check for any leaks, repair them, and evacuate the system.
0.4 - 0.6 (4 - 6) (56 - 85)Pressure on low pressure side is high. Pressure on high pressure side is low. Both pressure becoming equal right after A/C is turned OFF.Internal leak in compressor.Inspect compressor and repair or replace as necessary.
0.35 - 0.45 (3.5 - 4.5) (50 - 64)2.0 - 2.5 (20 - 25) (284 - 356)Pressure on both low and high pressure sides is high. Air bubbles are not visible even when engine rpm is lowered.Overcharged A/C system. Faulty condenser cooling operation. Faulty radiator or condenser cooling fan operation.Adjust refrigerant to specified amount. Clean condenser. Inspect and repair radiator or condenser cooling fan.
High pressure reading on both low and high pressure sides. Low pressure side tubing is not cold when touched. Air bubbles are visible through sight glass.Presence of air in A/C system (Improperly evacuated).Replace receiver / dryer. Inspect quantity of compressor oil and presence of contaminants in oil. Evacuate system and recharge with fresh refrigerant.
0.45 - 0.55 (4.5 - 5.5) (64 - 78)High pressure reading on both low and high pressure sides. Large amount of frost or dew on the low pressure side tubing.Faulty expansion valve. Refrigerant flow is not regulated properly.Replace expansion valve.

A/C SYSTEM PROBLEM DIAGNOSTIC CHART

Voltage Check

ECM and its circuits can be checked at ECM wiring couplers by measuring voltage.

CAUTIONECM cannot be checked by itself. It is strictly prohibited to connect voltmeter or ohmmeter to ECM with couplers disconnected from ECM.

Scheme 137

Scheme 137

Scheme 138

Scheme 138
  1. Remove ECM from vehicle by referring to «ENGINE CONTROL MODULE (ECM) REMOVAL AND INSTALLATION»(ref-251060-S32102796392007032000000) .
  2. Connect ECM couplers (1) to ECM (2).
  3. Check voltage at each terminal of couplers connected. NOTE: As each terminal voltage is affected by the battery voltage, confirm that the battery voltage is 11 V or more when ignition switch is ON position.

ECM Voltage Values Table for Relation of A/C Control

TerminalWire ColorCircuitNormal ValueCondition
G04-6BLK/REDMain power supply10 - 14 VIgnition switch ON
G04-7BLK/REDMain power supply10 - 14 VIgnition switch ON
G04-11BLU/ORNA/C refrigerant pressure switch0 - 1 VIgnition switch ON, A/C refrigerant pressure below 1100kPa (11 kg/cm 2 , 156 psi)
10 - 14 VIgnition switch ON, A/C refrigerant pressure above 1500kPa (15 kg/cm 2 , 213 psi)
G04-12GRN/BLKA/C switch10 - 14 VIgnition switch ON, A/C switch OFF
0 - 1.5 VIgnition switch ON, blower speed selector between 1st and HIGH position, A/C switch ON
G04-15ORNGround for sensorBelow 0.3 VIgnition switch ON
G04-24BLU/BLKElectric load signal for blower motor10 - 14 VIgnition switch ON, Blower speed selector OFF, 1st or 2nd position
0 - 2 VIgnition switch ON, Blower speed selector between 3rd and HIGH position
G04-25WHT/REDPower source for ECM internal memory10 - 14 VIgnition switch turned ON and OFF
G04-26WHT/BLKA/C evaporator outlet air temperature sensor signal2.35 - 2.8 VIgnition switch ON at A/C evaporator outlet air temperature 0°C (32°F)
1.5 - 1.9 VIgnition switch ON at A/C evaporator outlet air temperature 15°C (59°F)
0.9 - 1.15 VIgnition switch ON at A/C evaporator outlet air temperature 30°C (86°F)
G04-34YEL/WHTA/C evaporator inlet air temperature sensor signal2.35 - 2.8 VIgnition switch ON at A/C evaporator inlet air temperature 0°C (32°F)
1.5 - 1.9 VIgnition switch ON at A/C evaporator inlet air temperature 15°C (59°F)
0.9 - 1.15 VIgnition switch ON at A/C evaporator inlet air temperature 30°C (86°F)
C45-1BLU/YELA/C condenser fan motor relay output10 - 14 VIgnition switch ON, engine coolant temperature below 110°C (230°F)
0 - 1 VEngine running and A/C operated or engine coolant temperature over 110°C (230°F)
C45-2BLKGround for ECMBelow 0.3 VIgnition switch ON
C45-6BLK/ORNGround for ECMBelow 0.3 VIgnition switch ON
C45-23BRN/WHTMain power supply relay output10 - 14 VIgnition switch OFF
0 - 2 VIgnition switch ON
C45-28BRN/YELA/C compressor relay output10 - 14 VEngine running, A/C switch OFF
0 - 1 VEngine running, Blower speed selector between 1st and HIGH position, A/C switch ON
C46-6BLKGround for ECMBelow 0.3 VIgnition switch ON

ECM TERMINALS VOLTAGE SPECIFICATION

Quick Checking of Refrigerant Charge

The following procedure can be used for quickly checking whether the A/C system has a proper amount of refrigerant or not. Run engine at fast idle and operate A/C system at its maximum cooling capacity for a few minutes.

Then, look at the sight glass (1) on condenser outlet pipe (2) and compare what is observed with the symptoms listed in the table.

Checking Refrigerant Charge

StepActionYESNO
1Is there any bubble (3) in sight glass?Insufficient amount of refrigerant in A/C system. Charge proper amount of refrigerant in A/C system.Go to Step 2.
2Is there a difference in temperature between compressor inlet pipe and outlet pipe?Go to Step 3.Empty or nearly empty of refrigerant in A/C system. Charge proper amount of refrigerant in A/C system.
3Is any bubble (3) produced and cleared in a moment after A/C switch is turned OFF?Too much amount of refrigerant in A/C system. Charge proper amount of refrigerant in A/C System.Go to Step 4.
4Is any bubble (3) produced and cleared gradually after A/C switch is turned OFF?Perform A/C SYSTEM PERFORMANCE INSPECTION:MANUAL TYPE to check if proper amount of refrigerant is charged in A/C system.Charge proper amount of refrigerant in A/C system.

REFRIGERANT CHARGING INSPECTION CHART

CAUTIONDo not add any refrigerant in A/C system. Refrigerant charge has to be performed after refrigerant recovery and A/C system evacuation. For procedure of refrigerant charge, refer to OPERATION PROCEDURE FOR REFRIGERANT CHARGING: MANUAL TYPE .

Scheme 139

Scheme 139

Recovery

When evacuating A/C system, always recover refrigerant by using equipment for refrigerant recovery and recycling equipment. Discharging refrigerant HFC-134a (R-134a) into atmosphere would cause adverse effect to environments.

Note. After recovering refrigerant from system, the amount of removed compressor oil must be measured for replenishing compressor oil. When handling recovery and recycling equipment, be sure to follow the instruction manual for the equipment.

Scheme 140

Scheme 140: Recovery

Replenishing Compressor Oil

It is necessary to replenish specified amount of compressor oil to compressor (1) from compressor suction side hole (2) before evacuating and charging refrigerant.

Scheme 141

Scheme 141: Replenishing Compressor Oil

When charging refrigerant only

When charging refrigerant without replacing any component part, replenish the same amount of measured oil when recover refrigerant (if not measure, replenish 30 cm 3 (30 cc) oil).

When replacing compressor

Compressor oil is sealed in each new compressor by the amount required for A/C system. Therefore, when using a new compressor for replacement, drain excess oil from it by the amount calculated as follows.

"C"="A"-"B"

"C": Amount of oil to be drained

"A": Amount of oil sealed in a new compressor

"B": Amount of oil remaining in removed compressor

Note. Compressor assembly supplied from factory is filled up with the following amount of oil.

Oil amount in compressor

100 cm 3 (100 cc)

Scheme 142

Scheme 142: When replacing compressor

When replacing other part

Replenish the following amount of oil to compressor.

Amount of compressor oil to be replenished

Replaced part: Amount of compressor oil

Evaporator: 25 cm 3 (25 cc)

Condenser: 15 cm 3 (15 cc)

Desiccant: 20 cm 3 (20 cc)

Hoses: 10 cm 3 (10 cc) each

Pipes: 10 cm 3 (10 cc) each

Evacuating of A/C System

CAUTIONDo not evacuate before recovering refrigerant in system.

Note. Whenever opened (exposed to atmospheric air), the A/C system must be evacuated by using a vacuum pump. The A/C system should be attached with a manifold gauge set, and then should be evacuated for approximately 15 minutes.

  1. Connect high charging hose (1) and low charging hose (2) of manifold gauge set (3) respectively as follows: High charging hose (1) --> High pressure charging valve (4) on condenser outlet pipe Low charging hose (2) --> Low pressure charging valve (5) on suction pipe
  2. Attach center charging hose (6) of manifold gauge set (3) to vacuum pump (7).
  3. Operate vacuum pump (7), and then open discharge side valve (Hi) (8) of manifold gauge set (3). If there is no blockage in the system, there will be an indication on high pressure gauge (9). In this case, open the other side valve (Lo) (10) of the set and repair the system.
  4. Approximately 10 minutes later, low pressure gauge (11) should indicate -100 kPa (-1.0 kg/cm 2 , -760 mmHg, -14.7 psi) providing no leakage exists. NOTE: If the system does not indicate -100 kPa (-1.0 kg/cm 2 , -760 mmHg, -14.7 psi), close both valves, stop vacuum pump and watch movement of low pressure gauge. Increase in the gauge reading suggests existence of leakage. In this case, repair the system before continuing its evacuation. If the gauge shows a stable reading (suggesting no leakage), continue evacuation.
  5. Evacuation should be carried out for at least 15 minutes.
  6. Continue evacuation until low pressure gauge (11) indicates -100 kPa (-1.0 kg/cm 2 , -760 mmHg, -14.7 psi), and then close both valves (8), (10).
  7. Stop vacuum pump (7), and then disconnect center charging hose (6) from pump inlet. Now, the system is ready for charging refrigerant.

Scheme 143

Scheme 143

Checking of A/C System for Pressure Leaks

After completing the evacuation, close manifold gauge high pressure valve and low pressure valve, and then wait 10 minutes. Verify that low pressure gauge reading has not changed.

CAUTIONIf the gauge reading moves closer to "0", there is a leak somewhere. Inspect the tubing connections, make necessary repairs, and evacuate system once again, making sure that there are no leaks.

Procedure of Charging

CAUTIONAlways charge through low pressure side of A/C system at after the initial charging is performed from the high pressure side with the engine stopped. Never charge to high pressure side of A/C system with engine running. Do not charge while compressor is hot. When installing tap valve to refrigerant container to make a hole, carefully follow directions given by manufacturer. A pressure gauge should always be used before and during charging. The refrigerant container should be emptied of refrigerant when discarding it. The refrigerant container should not be heated up to 40°C (104°F) or over. Refrigerant container should not be reversed in direction during charging. Reversing in direction causes liquid refrigerant to enter compressor, causing troubles, such as compression of liquid refrigerant and the like.

Note. The air conditioning system uses HFC-134a (R-134a). Described here is a method to charge the air conditioning system with refrigerant from the refrigerant service container. When charging refrigerant recovered by using the refrigerant and recycling equipment (when recycling refrigerant), follow the procedure described in the equipment manufacturer's instruction manual.

Charging procedure

Charge proper amount of refrigerant accurately in accordance with the following procedure.

Specified amount of refrigerant

500 +/- 30 g (17.65 +/- 1.05 oz)

The initial charge of the A/C system is performed from the high pressure side with the engine stopped.

And next, this method must be followed by charging from the low pressure side with the engine running.

Scheme 144

Scheme 144: Charging procedure
  1. Check to make sure that hoses are routed properly after evacuating the system.
  2. Connect Low charging hose (1) and High charging hose (2) of the manifold gauge set (3) in position. Thus, open refrigerant container valve (4) to purge the charging line.
  3. Open the high pressure side valve (5) and charge refrigerant to system.
  4. After a while, open the low pressure side valve (6) and close the high pressure side valve (5). WARNING: Make sure that high pressure side valve is closed securely.
  5. Start engine and keep engine speed at 1500 r/min. Then, operate air conditioning at "DEF" or "DEF/FOOT" air flow mode.
  6. Charge A/C system with refrigerant. At this time, refrigerant container (4) should be held upright.
  7. Remove manifold gauge set as follows: WARNING: High pressure side is naturally under high pressure. So, care must be taken to protect your eyes and skin. Close low pressure side valve of manifold gauge set. (The high pressure side valve is closed continuously during the process of charging. Close refrigerant container valve. Stop engine. Using shop rag, remove charging hoses from service valves. This operation must be performed rapidly. Put caps on service valves.

Checking of A/C System for Refrigerant Leaks

Whenever a refrigerant leak is suspected in the system or any service operation has been performed which may result in disturbing lines or connections, it is advisable to test for leaks.

Common sense should be used in performing any refrigerant leak test, since the need and extent of any such test will, in general, depend upon the nature of a complaint and the type of a service performed on the system.

Liquid leak detectors

WARNINGTo prevent explosions or fires, make sure that there are no flammables in the vicinity. When exposed to fire, the refrigerant turns into a poisonous gas (phosgene). Do not inhale this gas.

There are a number of fittings and places throughout the air conditioning system where a liquid leak detector solution may be used to pinpoint refrigerant leaks.

By merely applying the solution to the area in question with a swab, such as attached to the cap of a vial, bubbles will form within seconds if there is a leak.

For confined areas, such as sections of the evaporator and condenser, an electronic (refrigerant) leak detector is more practical for determining leaks.

Special Tool

Scheme 145

Scheme 145
  1. 09990-86011

Scheme 146

Scheme 146: Heater and Cooling Unit Components

A/C Control Pressure Switch

  1. Run engine and A/C switch ON.
  2. Check continuity between "a" and "b" terminals of A/C refrigerant pressure switch (1) in normal A/C operating condition. If no continuity, replace A/C refrigerant pressure switch.

Scheme 147

Scheme 147: Radiator Cooling Fan and A/C Condenser Cooling Fan Control Pressure Switch
  1. Connect manifold gauge set to charging valves.
  2. Run engine and A/C switch ON.
  3. Check continuity between "c" and "d" terminals of A/C refrigerant pressure switch (1) when A/C refrigerant pressure is changed, as shown in figure. If operation is not as specified, replace A/C refrigerant pressure switch. A/C refrigerant pressure switch specifications "A": Approx. 200 kPa (2.0 kg/cm 2 , 28.5 psi) "B": Approx. 230 kPa (2.3 kg/cm 2 , 32.5 psi) "C": Approx. 2600 kPa (26 kg/cm 2 , 370 psi) "D": Approx. 3200 kPa (32 kg/cm 2 , 455 psi) "E": Approx. 1100 kPa (11 kg/cm 2 , 156 psi) "F": Approx. 1500 kPa (15 kg/cm 2 , 213 psi)

Scheme 148

Scheme 148: Compressor Relay and Condenser Cooling Fan Relay Inspection
  1. Disconnect negative (-) cable at battery.
  2. Remove condenser cooling fan relay (1) and compressor relay (2) from main fuse box.
  3. Check that there is no continuity between terminal "c" and "d". If there is continuity, replace relay.
  4. Check that there is continuity between terminals "c" and "d" when a 12 V battery is connected to terminals "a" and "b". If malfunction is found, replace it with a new one.

Magnet Clutch Components

CAUTIONNever disassemble compressor body assembly. Disassembly will affect original performance of A/C system.

Scheme 149

Scheme 149
MaterialSUZUKI recommended product or Specification
OilCompressor oil (ND-Oil8, 250cc)P/No.: 99000-27080

SERVICE MATERIAL SPECIFICATION

Note. Required service material is also described in the following. Precautions on Servicing A/C System: Manual Type

Air Bag Warning

Refer to AIR BAG WARNING .

Refer to A/C SYSTEM CAUTION: MANUAL TYPE .

Refer to PRECAUTION FOR CHARGING: MANUAL TYPE .

Refer to PRECAUTIONS ON SERVICING A/C SYSTEM: MANUAL TYPE .

Refer to REFRIGERANT TYPE CONSTRUCTION: MANUAL TYPE .

Refer to SUB-COOL SYSTEM DESCRIPTION: MANUAL TYPE .

Note. The diagnostic information as diagnostic trouble code (DTC) can be known by using SUZUKI scan tool (1). For further details, refer to DTC CHECK: AUTOMATIC TYPE .

HVAC control module (2) can detect malfunctions, which may occur in the following area.

  1. Outside air temperature sensor
  2. Inside air temperature sensor
  3. A/C evaporator outlet air temperature sensor
  4. Sunload sensor
  5. ECT sensor
  6. Temperature control actuator of heater and cooling unit
  7. Air flow control actuator of heater and cooling unit
  8. Temperature selector of HVAC control module
  9. Blower speed selector of HVAC control module
  10. Air flow selector of HVAC control module

When HVAC control module detects malfunction, the diagnostic information as diagnostic trouble code (DTC) is stored in the memory of the module. By performing the DTC CHECK procedure, the diagnostic information can be known by reading the flashing pattern of the fresh air indicator lamp (3) and recirculation indicator lamp (4).

For the procedure, refer to DTC CHECK: AUTOMATIC TYPE .

When HVAC control module detects malfunction, the rear defogger indicator lamp (5) flashes on and off for 15 seconds for a notice.

Scheme 150

Scheme 150

Major Components of A/C System

Refer to MAJOR COMPONENTS OF A/C SYSTEM: MANUAL TYPE .

Scheme 151

Scheme 151: A/C System Wiring Diagram

Reference Waveform

Note. The shape of waveform varies with engine coolant temperature.

Measurement terminalG77-24 to G77-25
Oscilloscope settingCH1: 5 V / DIV TIME: 200 ms / DIV
Measurement conditionIgnition switch turned ON

WAVEFORM REFERENCE

Waveform at 0°C (32°F)

Scheme 152

Scheme 152

Waveform at 40°C (104°F)

Scheme 153

Scheme 153

Waveform at 80°C (176°F)

ECM and its circuits can be checked at ECM wiring couplers by measuring voltage.

CAUTIONECM cannot be checked by itself. It is strictly prohibited to connect voltmeter or ohmmeter to ECM with couplers disconnected from ECM.

Scheme 154

Scheme 154

Scheme 155

Scheme 155
  1. Remove ECM from vehicle by referring to «ENGINE CONTROL MODULE (ECM) REMOVAL AND INSTALLATION»(ref-251060-S32102796392007032000000) .
  2. Connect ECM couplers (1) to ECM (2).
  3. Check voltage at each terminal of couplers connected. NOTE: As each terminal voltage is affected by the battery voltage, confirm that the battery voltage is 11 V or more when ignition switch is ON position.
TerminalWire ColorCircuitNormal ValueCondition
G04-6BLK/REDMain power supply10 - 14 VIgnition switch ON
G04-7BLK/REDMain power supply10 - 14 VIgnition switch ON
G04-9YEL/GRNEngine coolant temperature (ECT) signal outputSee reference waveform referring to INSPECTION OF HVAC CONTROL MODULE AND ITS CIRCUIT:AUTOMATIC TYPEIgnition switch ON
G04-11BLU/ORNA/C refrigerant pressure switch0 - 1 VIgnition switch ON, A/C refrigerant pressure below 1100 kPa (11 kg/cm 2 , 156 psi)
10 - 14 VIgnition switch ON, A/C refrigerant pressure above 1500 kPa (15 kg/cm 2 , 213 psi)
G04-12GRN/BLKA/C switch10 - 14 VIgnition switch ON, A/C switch OFF
0 - 1.5 VIgnition switch ON, blower speed selector between 1st and HIGH position, A/C switch ON
G04-24BLU/BLKElectric load signal for blower motor10 - 14 VIgnition switch ON, Blower speed selector OFF, 1st or 2nd position
0 - 2 VIgnition switch ON, Blower speed selector between 3rd and HIGH position
G04-25WHT/REDPower source for ECM internal memory10 - 14 VIgnition switch turned ON and OFF
C45-1BLU/YELA/C condenser fan motor relay output10 - 14 VIgnition switch ON, engine coolant temperature below 110°C (230°F)
0 - 1 VEngine running and A/C operated or engine coolant temperature over 110°C (230°F)
C45-2BLKGround for ECMBelow 0.3 VIgnition switch ON
C45-6BLK/ORNGround for ECMBelow 0.3 VIgnition switch ON
C45-23BRN/WHTMain power supply relay output10 - 14 VIgnition switch OFF
0 - 2 VIgnition switch ON
C45-28BRN/YELA/C compressor relay output10 - 14 VEngine running, A/C switch OFF
0 - 1 VEngine running, Blower speed selector between 1st and HIGH position, A/C switch ON
C46-6BLKGround for ECMBelow 0.3 VIgnition switch ON
C46-12LT GRNEngine coolant temperature (ECT) sensor signal3.7 - 3.85 VIgnition switch ON, engine coolant temperature 0°C (32°F)
1.45 - 1.6 VIgnition switch ON, engine coolant temperature 50°C (122°F)
0.4 - 0.5 VIgnition switch ON, engine coolant temperature 100°C (210°F)
C46-16ORNGround for sensorsBelow 0.3 VIgnition switch ON

ECM TERMINALS VOLTAGE SPECIFICATION

Refer to QUICK CHECKING OF REFRIGERANT CHARGE: MANUAL TYPE .

Refer to MAGNET CLUTCH COMPONENTS: MANUAL TYPE .