Automatic Air Conditioner: Other Nissan Murano Z50

Precautions for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT PRE-TENSIONER"

The Supplemental Restraint System such as "AIR BAG" and "SEAT BELT PRE-TENSIONER", used along with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted. Information necessary to service the system safely is included in the SUPPLEMENTAL RESTRAINT SYSTEM and SEAT BELTS articles .

Precautions for Working with HFC-134a (R-134a)

CONTAMINATED REFRIGERANT

If a refrigerant other than pure HFC-134a (R-134a) is identified in a vehicle, your options are

1. Explain to the customer that environmental regulations prohibit the release of contaminated refrigerant into the atmosphere.
2. Explain that recovery of the contaminated refrigerant could damage your service equipment and refrigerant supply.
3. Suggest the customer return the vehicle to the location of previous service where the contamination may have occurred.
4. If you choose to perform the repair, recover the refrigerant using only dedicated equipment and containers. Do not recover contaminated refrigerant into your existing service equipment. If your facility does not have dedicated recovery equipment, you may contact a local refrigerant product retailer for available service. This refrigerant must be disposed of in accordance with all federal and local regulations. In addition, replacement of all refrigerant system components on the vehicle is recommended.
5. If the vehicle is within the warranty period, the air conditioner warranty is void. Please contact Nissan Customer Affairs for further assistance.

General Refrigerant Precautions

Lubricant Precautions

1. Use only specified lubricant for the HFC-134a (R-134a) A/C system and HFC-134a (R-134a) components. If lubricant other than that specified is used, compressor malfunction is likely to occur.
2. The specified HFC-134a (R-134a) lubricant rapidly absorbs moisture from the atmosphere. The following handling precautions must be observed: When removing refrigerant components from a vehicle, immediately cap (seal) the component to minimize the entry of moisture from the atmosphere. When installing refrigerant components to a vehicle, do not remove the caps (unseal) until just before connecting the components. Connect all refrigerant loop components as quickly as possible to minimize the entry of moisture into system. Only use the specified lubricant from a sealed container. Immediately reseal containers of lubricant. Without proper sealing, lubricant will become moisture saturated and should not be used.
3. Avoid breathing A/C refrigerant and lubricant vapor or mist. Exposure may irritate eyes, nose and throat. Remove HFC-134a (R-134a) from the A/C system, using certified service equipment meeting requirements of SAE J-2210 [HFC-134a (R-134a) recycling equipment], or J-2209 [HFC-134a (R-134a) recovery equipment]. If accidental system discharge occurs, ventilate work area before resuming service. Additional health and safety information may be obtained from refrigerant and lubricant manufacturers.
4. Do not allow lubricant (Nissan A/C System Oil Type S) to come in contact with styrofoam parts. Damage may result.

Precautions for Refrigerant Connection

A new type refrigerant connection has been introduced to all refrigerant lines except the following location.

1. Expansion valve to evaporator
2. Refrigerant pressure sensor to condenser

Precautions for Servicing Compressor

1. Plug all openings to prevent moisture and foreign matter from entering.
2. When the compressor is removed, store it in the same position as it is when mounted on the car.
3. When replacing or repairing compressor, follow «MAINTENANCE OF LUBRICANT QUANTITY IN COMPRESSOR»(ref-234022-S22177771082006052800000) exactly.
4. Keep friction surfaces between clutch and pulley clean. If the surface is contaminated, with lubricant, wipe it off by using a clean waste cloth moistened with thinner.
5. After compressor service operation, turn the compressor shaft by hand more than five turns in both directions. This will equally distribute lubricant inside the compressor. After the compressor is installed, let the engine idle and operate the compressor for one hour.
6. After replacing the compressor magnet clutch, apply voltage to the new one and check for usual operation.

RECOVERY/RECYCLING EQUIPMENT

Be certain to follow the manufacturer's instructions for machine operation and machine maintenance. Never introduce any refrigerant other than that specified into the machine.

ELECTRONIC LEAK DETECTOR

Be certain to follow the manufacturer's instructions for tester operation and tester maintenance.

VACUUM PUMP

The lubricant contained inside the vacuum pump is not compatible with the specified lubricant for HFC-134a (R-134a) A/C systems. The vent side of the vacuum pump is exposed to atmospheric pressure. So the vacuum pump lubricant may migrate out of the pump into the service hose. This is possible when the pump is switched off after evacuation (vacuuming) and hose is connected to it.

To prevent this migration, use a manual valve placed near the hose-to-pump connection, as follows.

1. Usually vacuum pumps have a manual isolator valve as part of the pump. Close this valve to isolate the service hose from the pump.
2. For pumps without an isolator, use a hose equipped with a manual shut-off valve near the pump end. Close the valve to isolate the hose from the pump.
3. If the hose has an automatic shut-off valve, disconnect the hose from the pump. As long as the hose is connected, the valve is open and lubricating oil may migrate.

Some one-way valves open when vacuum is applied and close under a no vacuum condition. Such valves may restrict the pump's ability to pull a deep vacuum and are not recommended.

Scheme 167

MANIFOLD GAUGE SET

Be certain that the gauge face indicates HFC-134a or R-134a. Be sure the gauge set has 1/2 - 16 ACME threaded connections for service hoses. Confirm the set has been used only with refrigerant HFC-134a (R-134a) and specified lubricants.

Scheme 168

SERVICE HOSES

Be certain that the service hoses display the markings described (colored hose with black stripe). All hoses must include positive shut-off devices (either manual or automatic) near the end of the hoses opposite the manifold gauge.

Scheme 169

SERVICE COUPLERS

Never attempt to connect HFC-134a (R-134a) service couplers to a CFC-12 (R-12) A/C system. The HFC-134a (R-134a) couplers will not properly connect to the CFC-12 (R-12) system. However, if an improper connection is attempted, discharging and contamination may occur.

Scheme 170

SERVICE COUPLERS REFERENCE DATA

Scheme 171

REFRIGERANT WEIGHT SCALE

Verify that no refrigerant other than HFC-134a (R-134a) and specified lubricants have been used with the scale. If the scale controls refrigerant flow electronically, the hose fitting must be 1/2 - 16 ACME.

CHARGING CYLINDER

Using a charging cylinder is not recommended. Refrigerant may be vented into air from cylinder's top valve when filling the cylinder with refrigerant. Also, the accuracy of the cylinder is generally less than that of an electronic scale or of quality recycle/recharge equipment.

Precautions for Leak Detection Dye

1. The A/C system contains a fluorescent leak detection dye used for locating refrigerant leaks. An ultraviolet (UV) lamp is required to illuminate the dye when inspecting for leaks.
2. Always wear fluorescence enhancing UV safety goggles to protect your eyes and enhance the visibility of the fluorescent dye.
3. The fluorescent dye leak detector is not a replacement for an electronic refrigerant leak detector. The fluorescent dye leak detector should be used in conjunction with an electronic refrigerant leak detector (J-41995) to pin-point refrigerant leaks.
4. For your safety and your customer's satisfaction, read and follow all manufacture's operating instructions and precautions prior to performing the work.
5. A compressor shaft seal should not be repaired because of dye seepage. The compressor shaft seal should only be repaired after confirming the leak with an electronic refrigerant leak detector (J-41995).
6. Always remove any remaining dye from the leak area after repairs are complete to avoid a misdiagnosis during a future service.
7. Do not allow dye to come into contact with painted body panels or interior components. If dye is spilled, clean immediately with the approved dye cleaner. Fluorescent dye left on a surface for an extended period of time cannot be removed.
8. Do not spray the fluorescent dye cleaning agent on hot surfaces (engine exhaust manifold, etc.).
9. Do not use more than one refrigerant dye bottle (1/4 ounce/7.4 cc) per A/C system.
10. Leak detection dyes for HFC-134a (R-134a) and CFC-12 (R-12) A/C systems are different. Do not use HFC-134a (R-134a) leak detection dye in CFC-12 (R-12) A/C system or CFC-12 (R-12) leak detector dye in HFC-134a (R-134a) A/C system or A/C system damage may result.
11. The fluorescent properties of the dye will remain for over three (3) years unless a compressor malfunction occurs.

Special Service Tools

The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.

Scheme 172

HFC-134a (R-134a) Service Tools and Equipment

Never mix HFC-134a (R-134a) refrigerant and/or its specified lubricant with CFC-12 (R-12) refrigerant and/or its lubricant.

Separate and non-interchangeable service equipment must be used for handling each type of refrigerant/lubricant.

Refrigerant container fittings, service hose fittings and service equipment fittings (equipment which handles refrigerant and/or lubricant) are different between CFC-12 (R-12) and HFC-134a (R-134a). This is to avoid mixed use of the refrigerants/lubricant.

Adapters that convert one size fitting to another must never be used: refrigerant/lubricant contamination will occur and compressor malfunction will result.

Scheme 173

Scheme 174

Scheme 175

Scheme 176

REFRIGERANT FLOW

The refrigerant flows in the standard pattern, that is, through the compressor, the condenser with liquid tank, through the evaporator, and back to the compressor. The refrigerant evaporation through the evaporator is controlled by an externally equalized expansion valve, located inside the evaporator case.

FREEZE PROTECTION

Under usual operating conditions, when the A/C is switched ON, the compressor runs continuously, and the evaporator pressure, and therefore, temperature is controlled by the compressor to prevent freeze up.

REFRIGERANT PRESSURE SENSOR

The refrigerant system is protected against excessively high- or low-pressure by the refrigerant pressure sensor, located on the condenser. If the system pressure rises above, or falls below the specifications, the refrigerant pressure sensor detects the pressure inside the refrigerant line and sends the voltage signal to the ECM. ECM makes the A/C relay go OFF and stops the compressor when pressure on the high-pressure side detected by refrigerant pressure sensor is over about 2,746 kPa (28 kg/cm 2 , 398 psi), or below about 134 kPa (1.4 kg/cm 2 , 20 psi).

PRESSURE RELIEF VALVE

The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor. When the pressure of refrigerant in the system increases to an unusual level [more than 3,727 kPa (38 kg/cm 2 , 540 psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into the atmosphere.

Scheme 177

Scheme 178

LUBRICANT

1. Name: NISSAN A/C System Oil Type S
2. Part number: KLH00-PAGS0

System Construction

A small network is constructed between the unified meter and A/C amp., air mix door motor, mode door motor and intake door motor. The unified meter and A/C amp. and motors are connected by data transmission lines and motor power supply lines. The LAN network is built through the ground circuits of the each door motor. Addresses, motor opening angle signals, motor stop signals and error checking messages are all transmitted through the data transmission lines connecting the unified meter and A/C amp. and the each door motor. The following functions are contained in LCUs built into the air mix door motor, the mode door motor and the intake door motor.

Scheme 179

1. Address
2. Motor opening angle signals
3. Data transmission
4. Motor stop and drive decision
5. Opening angle sensor (PBR function)
6. Comparison
7. Decision (Unified meter and A/C amp. indicated value and motor opening angle comparison)

TRANSMISSION DATA AND TRANSMISSION ORDER

Unified meter and A/C amp. data is transmitted consecutively to each of the door motors following the form (Scheme 180)

Scheme 180

Start

Initial compulsory signal sent to each of the door motors.

Address

Data sent from the unified meter and A/C amp. is selected according to data-based decisions made by the air mix door motor, mode door motor and intake door motor.

If the addresses are identical, the opening angle data and error check signals are received by the door motor LCUs. The LCUs then make the appropriate error decision. If the opening angle data is usual, door control begins.

If an error exists, the received data is rejected and corrected data received. Finally, door control is based upon the corrected opening angle data.

Opening Angle

Data that shows the indicated door opening angle of each door motor.

Error Check

Procedure by which sent and received data is checked for errors. Error data is then compiled. The error check prevents corrupted data from being used by the air mix door motor, mode door motor and intake door motor. Error data can be related to the following symptoms.

1. Malfunction electrical frequency
2. Poor electrical connections
3. Signal leakage from transmission lines
4. Signal level fluctuation

Stop Signal

At the end of each transmission, a stop operation, in-operation, or internal error message is delivered to the unified meter and A/C amp. This completes one data transmission and control cycle.

AIR MIX DOOR CONTROL (AUTOMATIC TEMPERATURE CONTROL)

The air mix door is automatically controlled so that in-vehicle temperature is maintained at a predetermined value by the temperature setting, ambient temperature, in-vehicle temperature and amount of sunload.

FAN SPEED CONTROL

Blower speed is automatically controlled based on temperature setting, ambient temperature, in-vehicle temperature, intake temperature, amount of sunload and air mix door position.

When pressing AUTO switch, the blower motor starts to gradually increase air flow volume.

When engine coolant temperature is low, the blower motor operation is delayed to prevent cool air from flowing.

INTAKE DOOR CONTROL

The intake doors are automatically controlled by the temperature setting, ambient temperature, in-vehicle temperature, intake temperature, amount of sunload and ON-OFF operation of the compressor.

OUTLET DOOR CONTROL

The outlet door is automatically controlled by the temperature setting, ambient temperature, in-vehicle temperature, intake temperature and amount of sunload.

Scheme 181

When A/C switch or DEF switch is pressed, unified meter and A/C amp. inputs compressor ON signal to BCM. BCM sends compressor ON signal to ECM, via CAN communication line.

ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant-pressure sensor signal, throttle angle, etc.). If it judges compressor can be turned ON, it sends compressor ON signal to IPDM E/R, via CAN communication line.

Upon receipt of compressor ON signal from ECM, IPDM E/R turns air conditioner relay ON to operate compressor.

DISPLAY SCREEN

Displays the operational status of the system.

AUTO SWITCH

1. The compressor, intake doors, air mix doors, outlet doors and blower speed are automatically controlled so that the in-vehicle temperature will reach, and be maintained at the set temperature selected by the operator.
2. When pressing AUTO switch, air inlet, air outlet, fan speed, and discharge air temperature are automatically controlled.

TEMPERATURE CONTROL DIAL (POTENTIO TEMPERATURE CONTROL) (DRIVER SIDE)

Increases or decreases the set temperature.

TEMPERATURE CONTROL DIAL (POTENTIO TEMPERATURE CONTROL) (PASSENGER SIDE)

1. Increases or decreases the set temperature.
2. When the temperature control dial is turned, the dual switch indicator will automatically illuminate.

RECIRCULATION (REC) SWITCH

1. When REC switch is ON, REC switch indicator turns ON, and air inlet is fixed to REC.
2. When REC switch is ON and is pressed for approximately 1.5 seconds or longer, REC and FRE switch indicators blink twice. Then, automatic control mode is entered. Inlet status is displayed even during automatically controlled.
3. When FRE switch is turned ON, or when compressor is turned from ON to OFF, REC switch is automatically turned OFF (fixed to FRE mode). REC mode can be re-entered by pressing REC switch again.
4. REC switch is not operated when DEF switch is turned ON, or at the D/F position.

FRESH (FRE) SWITCH

1. When FRE switch is ON, FRE switch indicator turns ON, and air inlet is fixed to FRE.
2. When FRE switch is ON and is pressed for approximately 1.5 seconds or longer, REC and FRE switch indicators blink twice. Then, automatic control mode is entered. Inlet status is displayed even during automatically controlled.
3. When REC switch is turned ON, FRE switch is automatically turned OFF (fixed to REC mode). FRE mode can be re-entered by pressing FRE switch again.

DEFROSTER (DEF) SWITCH

Positions the air outlet doors to the defrost position. Also positions the intake doors to the fresh air position.

REAR WINDOW DEFOGGER SWITCH

When illumination is ON, rear window is defogged.

OFF SWITCH

The compressor and blower are OFF, the intake doors are set to the fresh air position, and the air outlet doors are set to the foot (75% foot and 25% defrost) position.

A/C SWITCH

The compressor is ON or OFF.

(Pressing the A/C switch when the AUTO switch is ON will turn off the A/C switch and compressor.)

MODE SWITCH

Controls the air discharge outlets.

FAN CONTROL DIAL

Manually control the blower speed. Seven speeds are available for manual control (as shown on the display screen).

DUAL SWITCH (WITH LEFT AND RIGHT VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM)

1. When the DUAL switch indicator is not illuminated and the DUAL switch is pressed, the driver-side setting temperature and passenger-side setting temperature, can each be set independently.
2. When DUAL switch indicator is not illuminated and the DUAL switch is pressed, the driver-side setting temperature is applied to both sides.

Fail-Safe Function

1. If a communication error exists between unified meter and A/C amp. and A/C and AV switch for 30 seconds or longer, air conditioner is controlled under following conditions: Compressor: ON Air outlet: AUTO Air inlet: FRE (Fresh) Blower fan speed: AUTO Set temperature: Setting before communication error occurs.

Scheme 182

Scheme 183

Scheme 184

CONSULT-II Function (BCM)

CONSULT-II can display diagnostic item using the diagnostic test modes shown in CONSULT-II FUNCTION (BCM) .

CONSULT-II FUNCTION (BCM)

Auto Amp. Terminals and Reference Value

Measure voltage between each terminal and ground by following terminals and reference value for unified meter and A/C amp.

Scheme 185

Scheme 186

Scheme 187

Scheme 188

AUXILIARY MECHANISM: TEMPERATURE SETTING TRIMMER

The trimmer compensates for differences in range of +/- 3°C (+/- 6°F) between temperature setting (displayed digitally) and temperature felt by driver. Operating procedures for this trimmer are as follows

Scheme 189

1. Begin Self-diagnosis STEP-5 mode. Refer to «SELF-DIAGNOSIS FUNCTION»(ref-234022-S02315709702006052800000) .
2. Turn fan control dial clockwise to set system in auxiliary mode.
3. Display shows 61 in auxiliary mechanism. It takes approximately 3 seconds.
4. Turn temperature control dial (driver side) as desired. Temperature will change at a rate of 0.5°C (1.0°F) each time a dial is turned. CAUTION: A decimal point is not indicated when the display shows "°C".

When battery cable is disconnected, trimmer operation is canceled. Temperature set becomes that of initial condition, i.e. 0°C (0°F).

AUXILIARY MECHANISM: FOOT POSITION SETTING TRIMMER

Wind distribution ratio in FOOT mode can be set.

Operating procedures for this trimmer are as follows

Scheme 190

1. Begin Self-diagnosis STEP-5 mode. Refer to «SELF-DIAGNOSIS FUNCTION»(ref-234022-S02315709702006052800000) .
2. Turn fan control dial clockwise to set system in auxiliary mode.
3. Display shows 61 in auxiliary mechanism. It takes approximately 3 seconds.
4. Press the mode switch as desired.

AUXILIARY MECHANISM: INLET PORT MEMORY FUNCTION

When ignition switch is turned from OFF to ON, inlet port can be set to AUTO or manual.

Operating procedures for this trimmer are as follows

Scheme 191

1. Begin Self-diagnosis STEP-5 mode. Refer to «SELF-DIAGNOSIS FUNCTION»(ref-234022-S02315709702006052800000) .
2. Turn fan control dial clockwise to set system in auxiliary mode.
3. Display shows 61 in auxiliary mechanism. It takes approximately 3 seconds.
4. Press the recirculation (REC) and fresh (FRE) switch as desired.

CHECKING RECIRCULATION

1. Press recirculation (REC) switch one time. Recirculation indicator should illuminate.
2. Press fresh (FRE) switch one time. Fresh indicator should illuminate.
3. Listen for intake door position change (you should hear blower sound change slightly).

If NG, go to trouble diagnosis procedure for INTAKE DOOR MOTOR CIRCUIT .

If OK, continue the check.

Scheme 192

Note. Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at FRESH when the DEF or D/F is selected.

Scheme 193

1. Turn temperature control dial (driver side) counterclockwise until 18°C (60°F) is displayed.
2. Check for cold air at discharge air outlets.

If NG, go to trouble diagnosis procedure for INSUFFICIENT COOLING .

If OK, continue the check.

Scheme 194

1. Turn temperature control dial (driver side) clockwise until 32°C (90°F) is displayed.
2. Check for hot air at discharge air outlets.

If NG, go to trouble diagnosis procedure for INSUFFICIENT HEATING .

If OK, continue the check.

Scheme 195

1. Press AUTO switch and A/C switch.
2. A/C switch indicator will turn ON. Confirm that the compressor clutch engages (sound or visual inspection).

If NG, go to trouble diagnosis procedure for MAGNET CLUTCH CIRCUIT .

If OK, continue the check.

Scheme 196

1. Press AUTO switch and A/C switch.
2. Display should indicate AUTO. Confirm that the compressor clutch engages (sound or visual inspection). (Discharge air and blower speed will depend on ambient, in-vehicle, and set temperatures.)

If NG, go to trouble diagnosis procedure for POWER SUPPLY AND GROUND CIRCUIT FOR AUTO AMP. , then if necessary, trouble diagnosis procedure for MAGNET CLUTCH CIRCUIT .

If all operational checks are OK (symptom cannot be duplicated), go to malfunction Simulation Tests in HOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENT and perform tests as outlined to simulate driving conditions environment. If symptom appears, refer to SYMPTOM CHART and perform applicable trouble diagnosis procedures.

Power Supply and Ground Circuit for Auto Amp.

SYMPTOM: A/C system does not come on.

Scheme 197

Unified Meter and A/C Amp. (Automatic Amplifier)

The unified meter and A/C amp. has a built-in microcomputer which processes information sent from various sensors needed for air conditioner operation. The air mix door motor, mode door motor, intake door motor, blower motor and compressor are then controlled. The unified meter and A/C amp. is unitized with control mechanisms. When the various switches and temperature dials are operated, data is input to the unified meter and A/C amp. from the DISPLAY UNIT/ DISPLAY CONTROL UNIT using CAN communication.

Self-diagnostic functions are also built into unified meter and A/C amp. to provide quick check of malfunctions in the auto air conditioner system.

Scheme 198

Potentio Temperature Control (PTC)

The PTC is built into the A/C and AV switch. It can be set at an interval of 0.5°C (1.0°F) in the 18°C (60°F) to 32°C (90°F) temperature range by turning temperature control dial. The set temperature is displayed.

Scheme 199

LAN System Circuit

SYMPTOM: Mode door motor, intake door motor and/or air mix door motor(s) does not operate normally.

Scheme 200

Scheme 201

Scheme 202

Scheme 203

Scheme 204

Scheme 205

Scheme 206

Scheme 207

1. CHECK POWER SUPPLY FOR UNIFIED METER AND A/C AMP. Turn ignition switch ON. Check voltage between unified meter and A/C amp. harness connector M51 terminal 54 (L/W) and ground. 54 - Ground: Battery voltage OK or NG OK: GO TO 2 . NG: Replace unified meter and A/C amp.
2. CHECK SIGNAL FOR UNIFIED METER AND A/C AMP. Confirm A/C LAN signal between unified meter and A/C amp. harness connector M51 terminal 43 (L/B) and ground using an oscilloscope. OK or NG OK: GO TO 3 . NG: Replace unified meter and A/C amp.
3. CHECK POWER SUPPLY FOR MOTOR Check voltage between mode door motor harness connector M252 terminal 1 (L/W), driver side air mix door motor harness connector M253 terminal 1 (L/W), passenger side air mix door motor harness connector M254 terminal 1 (L/W), intake door motor harness connector M255 terminal 1 (L/W) and ground. 1 - Ground: Battery voltage OK or NG OK: GO TO 4 . NG: Repair harness or connector.
4. CHECK SIGNAL FOR MOTOR Confirm A/C LAN signal between mode door motor harness connector M252 terminal 3 (L/B), driver side air mix door motor harness connector M253 terminal 3 (L/B), passenger side air mix door motor harness connector M254 terminal 3 (L/B), intake door motor harness connector M255 terminal 3 (L/B) and ground using an oscilloscope. OK or NG OK: GO TO 5 . NG: Repair harness or connector.
5. CHECK MOTOR GROUND CIRCUIT Turn ignition switch OFF. Disconnect door motor connector. Check continuity between mode door motor harness connector M252 terminal 2 (B), driver side air mix door motor harness connector M253 terminal 2 (B), passenger side air mix door motor harness connector M254 terminal 2 (B), intake door motor harness connector M255 terminal 2 (B) and ground. 2 - Ground: Continuity should exist. OK or NG OK: GO TO 6 . NG: Repair harness or connector.
6. CHECK MOTOR OPERATION Turn ignition switch OFF. Disconnect each door motor connector. Reconnect each door motor connector. Turn ignition switch ON. Confirm operation of each door motor. OK or NG OK: (Return to operate normally.) Poor contact in motor connector. NG: (Does not operate normally.) GO TO 7 .
7. CHECK OPERATION OF AIR MIX DOOR MOTOR AND INTAKE DOOR MOTOR Turn ignition switch OFF. Disconnect mode, air mix (driver side, passenger side), and intake door motor connectors. Reconnect air mix (driver side, passenger side) and intake door motor connectors. Turn ignition switch ON. Confirm operation of air mix door motor (driver side, passenger side) and intake door motor. OK or NG OK: [Air mix (driver side, passenger side) and intake door motors operate normally.] Replace mode door motor. NG: [Air mix (driver side, passenger side) and intake door motors does not operate normally.] GO TO 8 .
8. CHECK OPERATION OF MODE DOOR MOTOR AND INTAKE DOOR MOTOR Turn ignition switch OFF. Disconnect air mix door motor (driver side, passenger side) connectors. Reconnect mode door motor connector. Turn ignition switch ON. Confirm operation of mode door motor and intake door motor. OK or NG OK: (Mode and intake door motors operate normally.) GO TO 10 . NG: (Mode and intake door motors does not operate normally.) GO TO 9 .
9. CHECK OPERATION OF MODE DOOR MOTOR AND AIR MIX DOOR MOTOR Turn ignition switch OFF. Disconnect intake door motor connector. Reconnect air mix door motor (driver side, passenger side) connectors. Turn ignition switch ON. Confirm operation of mode door motor and air mix door motor (driver side, passenger side). OK or NG OK: [Mode and air mix door motor (driver side, passenger side) operate normally.] Replace intake door motor. NG: [Mode and air mix door motor (driver side, passenger side) does not operate normally.] Replace display and A/C auto amp.
10. CHECK OPERATION OF AIR MIX DOOR MOTOR Turn ignition switch OFF. Disconnect air mix door motor (driver side) connector. Turn ignition switch ON. Confirm operation of air mix door motor (passenger side). OK or NG OK: [Air mix door motor (passenger side) operates normally.] Replace air mix door motor (driver side). NG: [Air mix door motor (passenger side) does not operate normally.] Replace air mix door motor (passenger side).

Mode Door Motor Circuit

SYMPTOM

1. Air outlet does not change.
2. Mode door motor does not operate normally.

Scheme 208

Component Parts

Mode door control system components are

1. Unified meter and A/C amp.
2. Mode door motor (LCU)
3. A/C LAN system (PBR built-in mode door motor, intake door motor and air mix door motor)
4. In-vehicle sensor
5. Ambient sensor
6. Sunload sensor
7. Intake sensor

Mode Door Motor

The mode door motor is attached to the heater & cooling unit. It rotates so that air is discharged from the outlet set by the unified meter and A/C amp. Motor rotation is conveyed to a link which activates the mode door.

Scheme 209

Air Mix Door Motor Circuit

SYMPTOM

1. Discharge air temperature does not change.
2. Air mix door motor does not operate.

Scheme 210

Air mix door control system components are

1. Unified meter and A/C amp.
2. Air mix door motor (LCU)
3. A/C LAN system (PBR built-in mode door motor, intake door motor and air mix door motor)
4. In-vehicle sensor
5. Ambient sensor
6. Sunload sensor
7. Intake sensor

Air Mix Door Motor

The air mix door motor is attached to the heater & cooling unit. It rotates so that the air mix door is opened or closed to a position set by the unified meter and A/C amp. Motor rotation is then conveyed through a shaft and the air mix door position is then feedback to the unified meter and A/C amp. by PBR built-in air mix door motor.

Scheme 211

Scheme 212

Air Mix Door Motor PBR Circuit

SYMPTOM

1. Discharge air temperature does not change.
2. PBR circuit is open or shorted.

Intake Door Motor Circuit

SYMPTOM

1. Intake door does not change.
2. Intake door motor does not operate normally.

Scheme 213

Intake door control system components are

1. Unified meter and A/C amp.
2. Intake door motor (LCU)
3. A/C LAN system (PBR built-in mode door motor, intake door motor and air mix door motor)
4. In-vehicle sensor
5. Ambient sensor
6. Sunload sensor
7. Intake sensor

Intake Door Motor

The intake door motor is attached to the intake unit. It rotates so that air is drawn from inlets set by the unified meter and A/C amp. Motor rotation is conveyed to a lever which activates the intake door.

Scheme 214

Blower Motor Circuit

SYMPTOM: Blower motor operation is malfunctioning.

Scheme 215

Fan speed control system components are

1. Unified meter and A/C amp.
2. A/C LAN system (PBR built-in mode door motor, intake door motor and air mix door motor)
3. In-vehicle sensor
4. Ambient sensor
5. Sunload sensor
6. Intake sensor

Scheme 216

Automatic Mode

In the automatic mode, the blower motor speed is calculated by the unified meter and A/C amp. based on input from the PBR, in-vehicle sensor, sunload sensor, intake sensor and ambient sensor. When the air flow is increased, the duty ratio of the blower fan motor's drive signal is changed at 8%/sec. to prevent a sudden increase in air flow.

In addition to manual air flow control and the usual automatic air flow control, starting air flow control, low water temperature starting control and high passenger compartment temperature starting control are available.

Starting Fan Speed Control

Start Up from COLD SOAK Condition (Automatic mode)

In a cold start up condition where the engine coolant temperature is below 56°C (133°F), the blower will not operate for a short period of time (up to 150 seconds). The exact start delay time varies depending on the ambient and engine coolant temperature.

In the most extreme case (very low ambient) the blower starting delay will be 150 seconds as described above. After this delay, the blower will operate at low speed until the engine coolant temperature rises above 56°C (133°F), at which time the blower speed will increase to the objective speed.

Start Up from Usual or HOT SOAK Condition (Automatic mode)

The blower will begin operation momentarily after the AUTO switch is pushed. The blower speed will gradually rise to the objective speed over a time period of 3 seconds or less (actual time depends on the objective blower speed).

Blower Speed Compensation

Sunload

When the in-vehicle temperature and the set temperature are very close, the blower will be operating at low speed. The low speed will vary depending on the sunload. During conditions of low or no sunload, the blower low speed is usual low speed (duty ratio 25%). During high sunload conditions, the unified meter and A/C amp. causes the blower speed to increase (duty ratio 49%).

Scheme 217

Brushless Motor

The blower motor utilizes a brush-less motor with a rotating magnet. Quietness is improved over previous motors where the brush was the point of contact and the coil rotated.

Scheme 218

Blower Motor

Confirm smooth rotation of the blower motor.

Scheme 219

1. Ensure that there are no foreign particles inside the blower unit.

Magnet Clutch Circuit

SYMPTOM: Magnet clutch does not engage.

Scheme 220

Low Temperature Protection Control

Unified meter and A/C amp. will turn the compressor ON or OFF as determined by a signal detected by intake sensor.

When intake air temperature is higher than 4°C (39°F), the compressor turns ON. The compressor turns OFF when intake air temperature is lower than 2.5°C (37°F).

Scheme 221

The refrigerant pressure sensor is attached to the condenser. Make sure that the A/C refrigerant pressure and the sensor output voltage are within the specified range (Scheme 223) Refer to REFRIGERANT PRESSURE SENSOR.

Scheme 222

Scheme 223

Insufficient Cooling

SYMPTOM: Insufficient cooling

Scheme 224

Scheme 225

Scheme 226

Insufficient Heating

SYMPTOM: Insufficient heating

Scheme 227

Memory Function

SYMPTOM: Memory function does not operate.

Scheme 228

Ambient Sensor

The ambient sensor is attached on the radiator core support (left side). It detects ambient temperature and converts it into a resistance value which is then input into the unified meter and A/C amp.

Scheme 229

AMBIENT TEMPERATURE INPUT PROCESS

The unified meter and A/C amp. includes a processing circuit for the ambient sensor input. However, when the temperature detected by the ambient sensor increases quickly, the processing circuit retards the unified meter and A/C amp. function. It only allows the unified meter and A/C amp. to recognize an ambient temperature increase of 0.33°C (0.6°F) per 100 seconds.

As an example, consider stopping for a few minutes after high speed driving. Although the actual ambient temperature has not changed, the temperature detected by the ambient sensor will increase. This is because the heat from the engine compartment can radiate to the front grille area, location of the ambient sensor.

After disconnecting ambient sensor connector E15, measure resistance between terminals 1 (B/R) and 2 (B/Y) at sensor side, using the table below.

Scheme 230

AMBIENT SENSOR TEMPERATURE/RESISTANCE SPECIFICATIONS

If NG, replace ambient sensor.

In-vehicle Sensor

The in-vehicle sensor is located on instrument driver lower panel. It converts variations in temperature of compartment air drawn from the aspirator into a resistance value. It is then input into the unified meter and A/C amp.

Scheme 231

Aspirator

The aspirator is located on driver's side of heater & cooling unit. It produces vacuum pressure due to air discharged from the heater & cooling unit, continuously taking compartment air in the aspirator.

Scheme 232

Scheme 233

Sunload Sensor

The sunload sensor is located on the passenger side front defroster grille. It detects sunload entering through windshield by means of a photo diode. The sensor converts the sunload into a current value which is then input into the unified meter and A/C amp.

Scheme 234

SUNLOAD INPUT PROCESS

The unified meter and A/C amp. also includes a processing circuit which averages the variations in detected sunload over a period of time. This prevents drastic swings in the ATC system operation due to small or quick variations in detected sunload.

For example, consider driving along a road bordered by an occasional group of large trees. The sunload detected by the sunload sensor will vary whenever the trees obstruct the sunlight. The processing circuit averages the detected sunload over a period of time, so that the (insignificant) effect of the trees momentarily obstructing the sunlight does not cause any change in the ATC system operation. On the other hand, shortly after entering a long tunnel, the system will recognize the change in sunload, and the system will react accordingly.

Measure voltage between unified meter and A/C amp. harness connector M51 terminal 50 (O) and ground.

If NG, replace sunload sensor.

Scheme 235

1. When checking sunload sensor, select a place where sun shines directly on it.

Scheme 236

Intake Sensor

The intake sensor is located on the heater and cooling unit. It converts temperature of air after it passes through the evaporator into a resistance value which is then input to the unified meter and A/C amp.

Scheme 237

After disconnecting intake sensor connector M256, measure resistance between terminals 1 (R/W) and 2 (B/Y) at sensor side, using the INTAKE SENSOR TEMPERATURE/RESISTANCE SPECIFICATIONS table below.

Scheme 238

INTAKE SENSOR TEMPERATURE/RESISTANCE SPECIFICATIONS

If NG, replace intake sensor.

FUNCTION

Air inside passenger compartment is kept clean at either recirculation or fresh mode by installing in-cabin microfilter into blower unit.

Scheme 239

Discharging Refrigerant

Scheme 240

Scheme 241

Scheme 242

Components

Refer to PRECAUTIONS FOR REFRIGERANT CONNECTION .

Scheme 243

Scheme 244

Scheme 245

Scheme 246

1. Use a refrigerant collecting equipment (for HFC-134a) to discharge the refrigerant.
2. Remove air duct (inlet). Refer to «AIR CLEANER AND AIR DUCT»(ref-233993-S13601402462006052800000) .
3. Remove engine undercover, using power tools.
4. Remove mounting nuts from low-pressure flexible hose and high-pressure flexible hose. CAUTION: Cap or wrap the joint of the pipe with suitable material such as vinyl tape to avoid the entry of air.
5. Disconnect compressor (magnet clutch) connector.
6. Remove A/C compressor belt. Refer to «DRIVE BELTS»(ref-233993-S14607392772006052800000) .
7. Remove idler pulley bracket.
8. Remove engine oil cooler mounting bolts, using power tools.
9. Remove mounting bolts from compressor, using power tools.
10. Remove compressor from passenger side of the vehicle.

Coil

Check coil for loose connection or cracked insulation.

Scheme 247

Scheme 248

Scheme 249

Scheme 250

1. Install field coil. Be sure to align coil's pin with the hole in the compressor's front head.
2. Install compressor connector.
3. Install pulley assembly using installer and a hand press, and then install snap ring using snap ring pliers.
4. Using holder to prevent clutch disc rotation. Tightening torque: 14 N.m (1.4 kg-m, 10 ft-lb) After tightening bolt, make sure pulley rotates smoothly.
5. Check clearance around entire periphery of clutch disc. Disc to pulley clearance: 0.3 - 0.60 mm (0.012 - 0.024 in) If the specified clearance is not obtained, replace adjusting spacer and readjust.

Checking for Refrigerant Leaks

Perform a visual inspection of all refrigeration parts, fittings, hoses and components for signs of A/C lubricant leakage, damage and corrosion. A/C lubricant leakage may indicate an area of refrigerant leakage. Allow extra inspection time in these areas when using either an electronic refrigerant leak detector or fluorescent dye leak detector.

If dye is observed, confirm the leak with an electronic refrigerant leak detector. It is possible a prior leak was repaired and not properly cleaned.

When searching for leaks, do not stop when one leak is found but continue to check for additional leaks at all system components and connections.

When searching for refrigerant leaks using an electronic leak detector, move the probe along the suspected leak area at 1 to 2 inches per second and no further than 1/4 inch from the component.

Checking System for Leaks Using the Fluorescent Leak Detector

1. Check A/C system for leaks using the UV lamp and safety goggles (J-42220) in a low sunlight area (area without windows preferable). Illuminate all components, fittings and lines. The dye will appear as a bright green/yellow area at the point of leakage. Fluorescent dye observed at the evaporator drain opening indicates an evaporator core assembly (tubes, core or expansion valve) leak.
2. If the suspected area is difficult to see, use an adjustable mirror or wipe the area with a clean shop rag or cloth, with the UV lamp for dye residue.
3. After the leak is repaired, remove any residual dye using dye cleaner (J-43872) to prevent future misdiagnosis.
4. Perform a system performance check and verify the leak repair with an approved electronic refrigerant leak detector.

Note. Other gases in the work area or substances on the A/C components, for example, anti-freeze, windshield washer fluid, solvents and lubricants, may falsely trigger the leak detector. Make sure the surfaces to be checked are clean.

Clean with a dry cloth or blow off with shop air.

Do not allow the sensor tip of the detector to contact with any substance. This can also cause false readings and may damage the detector.

Dye Injection

This procedure is only necessary when recharging the system or when the compressor has seized and was replaced.

1. Check A/C system static (at rest) pressure. Pressure must be at least 345 kPa (3.52 kg/cm 2 , 50 psi).
2. Pour one bottle (1/4 ounce/7.4 cc) of the A/C refrigerant dye into the injector tool (J-41459).
3. Connect the injector tool to the A/C LOW PRESSURE side service fitting.
4. Start engine and switch A/C ON.
5. When the A/C operating (compressor running), inject one bottle (1/4 ounce/7.4 cc) of fluorescent dye through the low-pressure service valve using dye injector tool J-41459 (refer to the manufacture's operating instructions).
6. With the engine still running, disconnect the injector tool from the service fitting. CAUTION: Be careful the A/C system or replacing a component, pour the dye directly into the open system connection and proceed with the service procedures.
7. Operate the A/C system for a minimum of 20 minutes to mix the dye with the system oil. Depending on the leak size, operating conditions and location of the leak, it may take from minutes to days for the dye to penetrate a leak and become visible.

PRECAUTIONS FOR HANDLING LEAK DETECTOR

When performing a refrigerant leak check, use an A/C leak detector (J-41995) or equivalent. Ensure that the instrument is calibrated and set properly per the operating instructions.

The leak detector is a delicate device. In order to use the leak detector properly, read the operating instructions and perform any specified maintenance.

Scheme 251

Scheme 252

Scheme 253

Scheme 254

1. Position probe approximately 5 mm (3/16 in) away from point to be checked.
2. When testing, circle each fitting completely with probe.
3. Move probe along component approximately 25 to 50 mm (1 to 2 in)/sec.

CHECKING PROCEDURE

To prevent inaccurate or false readings, make sure there is no refrigerant vapor, shop chemicals, or cigarette smoke in the vicinity of the vehicle. Perform the leak test in calm area (low air/wind movement) so that the leaking refrigerant is not dispersed.

Scheme 255

1. Turn engine OFF.
2. Connect a suitable A/C manifold gauge set to the A/C service ports.
3. Check if the A/C refrigerant pressure is at least 345 kPa (3.52 kg/cm 2, 50 psi) above 16°C (61°F). If less than specification, recover/evacuate and recharge the system with the specified amount of refrigerant. NOTE: At temperatures below 16°C (61°F), leaks may not be detected since the system may not reach 345 kPa (3.52 kg/cm 2, 50 psi).
4. Perform the leak test from the high-pressure side (compressor discharge a to evaporator inlet g) to the low side (evaporator drain hose h to shaft seal m). Refer to «COMPONENTS»(ref-234022-S35152859912006052700000). Perform a leak check for the following areas carefully. Clean the component to be checked and move the leak detected probe completely around the connection/component. Compressor Check the fitting of high- and low-pressure flexible hoses, relief valve and shaft seal. Condenser Check the fitting of high-pressure flexible hose and pipe, refrigerant pressure sensor. Liquid tank Check the refrigerant connection. Service valves Check all around the service valves. Ensure service valve caps are secured on the service valves (to prevent leaks). NOTE: After removing A/C manifold gauge set from service valves, wipe any residue from valves to prevent any false readings by leak detector. Cooling unit (Evaporator) With engine OFF, turn blower fan on "High" for at least 15 seconds to dissipate any refrigerant trace in the cooling unit. Wait a minimum of 10 minutes accumulation time (refer to the manufacturer's recommended procedure for actual wait time) before inserting the leak detector probe into the drain hose. Keep the probe inserted for at least 10 seconds. Use caution not to contaminate the probe tip with water or dirt that may be in the drain hose.
5. If a leak detector detects a leak, verify at least once by blowing compressed air into area of suspected leak, then repeat check as outlined above.
6. Do not stop when one leak is found. Continue to check for additional leaks at all system components. If no leaks are found, perform steps 7 - 10.
7. Start engine.
8. Set the heater A/C control as follows; A/C switch: ON MODE switch: VENT (Ventilation) Intake position: Recirculation Max. cold temperature Fan speed: High
9. Run engine at 1,500 rpm for at least 2 minutes.
10. Turn engine off and perform leak check again following steps 4 through 6 above. Refrigerant leaks should be checked immediately after stopping the engine. Begin with the leak detector at the compressor. The pressure on the high pressure side will gradually drop after refrigerant circulation stops and pressure on the low pressure side will gradually rise (Scheme 256) Some leaks are more easily detected when pressure is high.
11. Before connecting recovery/recycling recharging equipment to vehicle, check recovery/recycling recharging equipment gauges. No refrigerant pressure should be displayed. If pressure is displayed, recover refrigerant from equipment lines and then check refrigerant purity.
12. Confirm refrigerant purity in supply tank using recovery/recycling recharging equipment and refrigerant identifier.
13. Confirm refrigerant purity in vehicle A/C system using recovery/recycling recharging equipment and refrigerant identifier.
14. Discharge A/C system using approved refrigerant recovery equipment. Repair the leaking fitting or component if necessary.
15. Evacuate and recharge A/C system and perform the leak test to confirm no refrigerant leaks.
16. Perform A/C performance test to ensure system works properly.

Compressor

COMPRESSOR SPECIFICATIONS

Scheme 256

Refrigerant

REFRIGERANT SPECIFICATIONS

Engine Idling Speed

Refer to IDLE SPEED AND IGNITION TIMING CHECK .

Belt Tension

Refer to DRIVE BELTS .