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Fig. 17: Air Bag System Wiring Diagram (1990 RX7)
Courtesy of MAZDA MOTORS CORP.
1991 Mazda MX-5 Miata
AIR BAG RESTRAINT SYSTEM MAZDA 1990-91 AIR BAGS
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Page 151 of 392
Fig. 18: Air Bag System Wiring Diagram (1991 Miata)
Courtesy of MAZDA MOTORS CORP.
1991 Mazda MX-5 Miata
AIR BAG RESTRAINT SYSTEM MAZDA 1990-91 AIR BAGS
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Page 152 of 392
Fig. 19: Air Bag System Wiring Diagram (1991 RX7)
Courtesy of MAZDA MOTORS CORP.
1991 Mazda MX-5 Miata
AIR BAG RESTRAINT SYSTEM MAZDA 1990-91 AIR BAGS
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Page 315 of 392
1 - 30 Amp (Pink) Headlights
2 - 30 Amp (Pink) Fuel Injection, Alternator
3 - 80 Amp (Black) Protection Of All Circuits
4 - 40 Amp (Green) Taillights, Shift Lock, Cruise Control, Horn, Stoplights, Hazard Warning Lights,
Interior Lights, Warning Buzzers, Radio/Cassette, Compact Disc Player, Clock
5 - Empty (1990); 60 Amp (Yellow) (1991-94) Anti-Lock Brake System
6 - 30 Amp (Pink) Cooling Fan
7 - 10 Amp (Red) Air Bag
8 - 20 Amp (Yellow) A/C Additional Fan
9 - 10 Amp (Red) Fuel Injection
10 - 30 Amp (Pink) Headlight Retractor
TRUNK MOUNTED FUSE PANEL IDENTIFICATION
1991 Mazda MX-5 Miata
FUSES & CIRCUIT BREAKERS Fuses & Circuit Breakers 1990-95 Mazda
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Page 317 of 392
Fig. 3: Interior Fuse Panel Identification
Courtesy of MAZDA MOTOR OF AMERICA, INC.
Fuse & Circuit Breaker Identification
11 - 15 Amp (Blue) Engine Cooling Fan
12 - 10 Amp (Red) Gauges, Warning Lights, Turn Signal Lights, Cruise Control
13 - 15 Amp (Blue) Air Bag
14 - 30 Amp Heater
15 - Empty
16 - 30 Amp (Green) Power Windows
17 - 20 Amp (Yellow) Wipers, Washers
18 - Empty
19 - 15 Amp (Blue) Taillights
20 - Empty
21 - 15 Amp (Blue) Shift Lock, Cruise Control, Horn, Stoplights
22 - 15 Amp (Blue) Hazard Warning Lights
1991 Mazda MX-5 Miata
FUSES & CIRCUIT BREAKERS Fuses & Circuit Breakers 1990-95 Mazda
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23 - Empty
24 - 10 Amp (Red) Interior Lights, Warning Buzzers, Radio/Cassette, Compact Disc Player, Clock
25 - 15 Amp (Blue) Radio/Cassette, Compact Disc Player, Clock, Cigarette Lighter
26 - Empty
27 - Empty
BATTERY SPECIFICATIONS
Vehicle is equipped with a special 9 9/16" x 4 3/4" x 7 3/8" 12-volt battery that is vented to outside of vehicle.
CAUTIONS & WARNINGS
SUPPLEMENTAL RESTRAINT SYSTEM (AIR BAG)
Modifications or improper maintenance, including incorrect removal and installation of the Supplemental
Restraint System (SRS), can adversely affect system performance. DO NOT cover, obstruct or change the
steering wheel horn pad in any way, as such action could cause improper function of the system. Use only plain
water when cleaning the horn pad. Solvents or cleaners could adversely affect the air bag cover and cause
improper deployment of the system.
AIR CONDITIONING SERVICING CAUTION: When battery is disconnected, vehicles equipped with computers may
lose memory data. When battery power is restored, driveability problems
may exist on some vehicles. These vehicles may require a relearn
procedure. See COMPUTER RELEARN PROCEDURES article in the
GENERAL INFORMATION Section.
NOTE: See the AIR BAGS article in the ACCESSORIES/SAFETY EQUIPMENT Section.
WARNING:To avoid injury from accidental air bag deployment, read and carefully
follow all warnings and service precautions. See appropriate AIR BAGS
article in ACCESSORIES/SAFETY EQUIPMENT.
CAUTION: Disconnect negative battery cable before servicing any air bag system,
steering column or passenger side dash component. After any repair, turn
ignition key to the ON position from passenger's side of vehicle in case of
accidental air bag inflation
CAUTION: Avoid breathing R-134a refrigerant and PAG lubricant vapors, exposure
may irritate eyes, nose and throat. To remove R-134a from system use R-
134a recycling equipment that meets SAE J2210 specifications. If
accidental system discharge occurs, ventilate work area before resuming
1991 Mazda MX-5 Miata
FUSES & CIRCUIT BREAKERS Fuses & Circuit Breakers 1990-95 Mazda
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Page 321 of 392

HEATER SYSTEM
1990-92 Heater Systems
DESCRIPTION & OPERATION
Heater case, mounted under center of instrument panel, contains airflow mode door and air-mix (temperature
blend) door. See Fig. 1
. Blower case, mounted under right end of instrument panel, contains recirculated/fresh
air door. All doors are controlled manually from control panel by cable.
Blower motor relay, in left rear corner of engine compartment (on relay cluster), supplies power to blower
motor. Blower resistors, on bottom of blower case, determine blower speed.
Fig. 1: Exploded View of Heater Case
Courtesy of MAZDA MOTORS CORP. WARNING:To avoid injury from accidental air bag deployment, read and carefully
follow all SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR
BAG SYSTEM procedures in AIR BAG article in the
ACCESSORIES/SAFETY EQUIPMENT Section.
1991 Mazda MX-5 Miata
HEATER SYSTEM 1990-92 Heater Systems
1991 Mazda MX-5 Miata
HEATER SYSTEM 1990-92 Heater Systems
Microsoft
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ADJUSTMENTS
AIRFLOW MODE DOOR
Set airflow mode control lever to vent position. Disconnect control cable at airflow mode door lever. Extend
airflow mode door lever until it stops, and hold it there. See Fig. 1
. Attach control cable to door lever and clip.
Ensure control lever moves freely between defrost and vent positions.
AIR-MIX (TEMPERATURE BLEND) DOOR
Set temperature control lever to maximum hot position. Disconnect control cable at air-mix door lever. See Fig.
1 . Extend air-mix door lever until it stops, and hold it there. Attach control cable to door lever and clip. Ensure
control lever moves freely between hot and cold positions.
RECIRCULATED/FRESH AIR DOOR
Set recirculated/fresh air control lever to fresh position. Disconnect control cable at recirculated/fresh air door
lever. Retract recirculated/fresh air door lever until it stops, and hold it there. Attach control cable to door lever
and clip. Ensure control lever moves freely between recirculated air and fresh air positions.
TESTING
BLOWER MOTOR CIRCUIT
1. Check 30-amp HEATER circuit breaker in passenger compartment fuse panel. If Red button has not
popped out, go to next step. If Red button has popped out, repair short circuit and press Red button to
reset circuit breaker.
2. Turn ignition on. Turn blower switch to 4th position (high). Check voltage at Blue wire terminal of 2-
wire blower motor connector on bottom of blower case. If no voltage is present, repair wiring between
circuit breaker and blower motor.
3. If battery voltage is present, turn off blower switch and A/C switch (if equipped). Check voltage at
Blue/Red wire terminal of blower resistor 1-wire connector. If no voltage is present, replace blower
motor. If battery voltage is present, check voltage at Blue/White wire terminal of blower resistor
connector.
4. If no volta
ge is present, replace blower resistor. If battery voltage is present, check voltage at Blue/Red WARNING:To avoid injury from accidental air bag deployment, read and carefully
follow all SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR
BAG SYSTEM procedures in AIR BAG article in the
ACCESSORIES/SAFETY EQUIPMENT Section.
NOTE: Blower resistor uses a 1-wire connector and a 4-wire connector. The wire
in the 1-wire connector is Blue/Red, and one of the wires in the 4-wire
connector is Blue/Red. Check voltage at appropriate wire.
1991 Mazda MX-5 Miata
HEATER SYSTEM 1990-92 Heater Systems
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