1997 MAZDA MX-5 Factory Repair Manual

Disconnect A/C switch connector. Turn A/C switch on. Check continuity between indicated terminals. See A/C
SWITCH TEST table. See Fig. 1 . Replace A/C switch if continuity is not as specified.
A/C SWITCH TEST
Fig. 1: Identifying A/C Switch Terminals

Courtesy of MAZDA MOTORS CORP.
A/C RELAY
Remove relay. Check continuity between indicated relay terminals. See A/C RELAY TEST table. See Fig. 2
.
Replace relay if continuity is not as specified.
A/C RELAY TEST
TerminalContinuity
"D" & "A"(1) Yes
"F" & "A"(1) Yes
(1)Continuity exists in only one direction.
Test Between TerminalsContinuity
"A" & "B"(1) Yes
"C" & "D"(1) No
"C" & "D"(2) Yes
(1)With no voltage applied.
(2)With battery voltage applied to terminals "A" and "B".

1997 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1997 Manual A/C-Heater System
Microsoft
Sunday, July 05, 2009 1:41:48 PMPage 4 © 2005 Mitchell Repair Information Company, LLC.

Fig. 2: Identifying A/C Relay Terminals
Courtesy of MAZDA MOTORS CORP.
CONDENSER FAN RELAY
Remove condenser fan relay. Check continuity between indicated relay terminals. See CONDENSER FAN
RELAY TEST table. See Fig. 3 . If continuity is not as specified, replace relay.
CONDENSER FAN RELAY TEST
Test Between TerminalsContinuity
"A" & "B"(1) Yes
"C" & "E"(1) No
"C" & "F"(1) Yes
"C" & "E"(2) Yes
(1)With no voltage applied.
(2)With battery voltage applied to terminals "A" and "B".

1997 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1997 Manual A/C-Heater System
Microsoft
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Fig. 3: Identifying Condenser Fan Relay Terminals
Courtesy of MAZDA MOTORS CORP.
CONDENSER FAN MOTOR
Disconnect condenser fan motor connector. Connect positive battery lead to condenser fan motor Black/Yellow
wire terminal, and ground Black wire terminal. Replace condenser fan motor if it does not operate.
EVAPORATOR THERMOSWITCH
1. Remove glove box. Operate engine at idle. Turn A/C off. Turn blower switch to 4th position (high) for a
few minutes to ensure evaporator temperature is greater than 32°F (0°C). Turn blower switch and engine
off.
2. Disconnect evaporator thermoswitch connector. Check continuity between thermoswitch terminals. If
continuity exists, go to next step. If there is no continuity, replace thermoswitch.
3. Submerge thermoswitch sensing bulb in ice cold water of less than 32°F (0°C). Ensure continuity does
not exist between thermoswitch terminals. Replace thermoswitch if continuity is not as specified.
PRESSURE SWITCH
1. Turn ignition off. Connect manifold pressure gauge set to system. If high-side pressure is 37-310 psi (2.6-
22.0 kg/cm
2 ), go to next step. If pressure is not as specified, check refrigerant level.
2. Disconnect pressure switch connector. Check continuity between switch terminals. If continuity exists,
pressure switch is okay. If there is no continuity, replace pressure switch.
REMOVAL & INSTALLATION

1997 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1997 Manual A/C-Heater System
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COMPRESSOR
Removal & Installation
1. Before disconnecting negative battery cable, obtain radio anti-theft code from vehicle owner. Disconnect
negative battery cable.
2. Raise and support front of vehicle with safety stands. Discharge A/C system using approved refrigerant
recovery/recycling equipment. Remove splash shield and air guide.
3. Disconnect compressor clutch connector. Disconnect refrigerant lines from compressor, and plug open
fittings. Remove compressor drive belt. Remove compressor bolts and compressor. To install, reverse
removal procedure. Adjust drive belt deflection. Apply clean compressor oil to "O" ring before
connecting fittings. DO NOT apply compressor oil to fitting nuts. Evacuate and charge A/C system.
Check for leaks.
CONDENSER & RECEIVER-DRIER
Removal
Raise and support front of vehicle with safety stands. Discharge A/C system using approved refrigerant
recovery/recycling equipment. Remove splash shield and air guide. Remove condenser. Remove receiver-drier.
Plug open fittings.
Installation
To install, reverse removal procedure. Apply clean compressor oil to "O" rings before connecting fittings. DO
NOT apply compressor oil to fitting nuts. If installing new condenser, add 1.0 ounce of compressor oil to A/C
compressor. If installing new receiver-drier, add .3 ounce of compressor oil to A/C compressor. Evacuate and
charge A/C system. Check for leaks.
EVAPORATOR UNIT
Removal
1. Discharge A/C system using approved refrigerant recovery/recycling equipment. Disconnect refrigerant
pipes from evaporator tubes at engine compartment firewall and plug open fittings. Remove passenger-
side instrument panel undercover. Remove glove box.
2. Disconnect electrical connectors. Loosen seal plates between evaporator unit, heater unit and blower unit.
Remove evaporator unit. Disassemble evaporator unit to remove evaporator core and thermo-switch. See WARNING:To avoid injury from accidental air bag deployment, read and follow all
SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR BAG
SYSTEM procedures in AIR BAG RESTRAINT SYSTEM article in the
ACCESSORIES/SAFETY EQUIPMENT section.
NOTE: For removal and installation procedures not covered in this article, see HEATER
SYSTEM article.

1997 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1997 Manual A/C-Heater System
Microsoft
Sunday, July 05, 2009 1:41:48 PMPage 7 © 2005 Mitchell Repair Information Company, LLC.

Fig. 4 .
Installation
To install, reverse removal procedure. Apply clean compressor oil to "O" rings before connecting fittings. DO
NOT apply compressor oil to fitting nuts. If installing new evaporator, add 1.7 ounces of compressor oil to A/C
compressor. Evacuate and charge A/C system. Check for leaks.
Fig. 4: Exploded View Of Evaporator Unit

Courtesy of MAZDA MOTORS CORP.
TORQUE SPECIFICATIONS

1997 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1997 Manual A/C-Heater System
Microsoft
Sunday, July 05, 2009 1:41:48 PMPage 8 © 2005 Mitchell Repair Information Company, LLC.

TORQUE SPECIFICATIONS
WIRING DIAGRAM
ApplicationFt. Lbs. (N.m)
Compressor Bracket-To-Engine Bolt28-38 (38-51)
Compressor-To-Compressor Bracket Bolt11-15 (15-21)
Refrigerant Pipe Fittings
Condenser Inlet11-18 (15-24)
Evaporator Outlet15-21 (20-29)
INCH Lbs. (N.m)
Evaporator Unit Nut71-97 (8-11)
Refrigerant Pipe Fittings
Compressor Inlet & Outlet89-132 (10-15)
Evaporator Inlet89-168 (10-19)
Receiver-Drier Inlet & Outlet89-168 (10-19)
Steering Wheel Nut79-121 (9-14)

1997 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1997 Manual A/C-Heater System
Microsoft
Sunday, July 05, 2009 1:41:48 PMPage 9 © 2005 Mitchell Repair Information Company, LLC.

1997 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1997 Manual A/C-Heater System
Microsoft
Sunday, July 05, 2009 1:41:48 PMPage 10 © 2005 Mitchell Repair Information Company, LLC.

Fig. 5: Manual A/C-Heater System Wiring Diagram

1997 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1997 Manual A/C-Heater System
Microsoft
Sunday, July 05, 2009 1:41:48 PMPage 11 © 2005 Mitchell Repair Information Company, LLC.