1991 MAZDA MIATA electrical

CONTROL UNITS LOCATION
SENDING UNITS & SENSORS
SENDING UNITS & SENSORS LOCATION
MOTORS
MOTORS LOCATION
SOLENOIDS & SOLENOID VALVES
SOLENOIDS & SOLENOID VALVES LOCATION
ComponentLocation
ABS Control UnitBehind center of dash, near ECU.
Cruise Control UnitBehind left side of dash, above fuse block.
Engine Control Unit (ECU)Behind center of dash. See Fig. 2 .
Supplemental Safety Restraint (SRS)
ModuleBehind left side of dash. See Fig. 3 .
ComponentLocation
ABS Wheel SensorsOn each front & rear wheel hub
assembly.
Airflow MeterConnected to air filter housing. See Fig.
2 .
Atmospheric Pressure SensorBuilt-in ECU.
Brake Fluid Level SensorInside brake master cylinder.
Coolant Temperature SensorOn water outlet, at left rear of engine. See
Fig. 2
.
Cooling Fan ThermoswitchOn thermostat housing.
Crank Angle SensorOn right rear side of cylinder head. See
Fig. 2
.
Intake Air ThermosensorIn airflow sensor unit.
Oil Pressure SensorOn left side of engine near oil filter.
SRS Crash/Impact Sensors
FrontOn center, left and right front of
vehicle. See Fig. 3
.
CenterBehind center of dash. See Fig. 3 .
Throttle Position Sensor (TPS)Mounted on side of throttle body. See
Fig. 2
.
ComponentLocation
A/C-Heater Blower MotorBehind left side of dash.
Wiper MotorOn right side of firewall.

1991 Mazda MX-5 Miata
ELECTRICAL COMPONENT LOCATOR 1991 MAZDA ELECTRICAL COMPONENTS
Microsoft
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SWITCHES
SWITCHES LOCATION
MISCELLANEOUS
MISCELLANEOUS LOCATION
COMPONENT LOCATION GRAPHICS
ComponentLocation
Idle Speed Control SolenoidOn throttle body.
Purge Control Solenoid ValveOn right side of engine compartment, on shock
tower.
ComponentLocation
A/C Pressure SwitchOn high pressure refrigerant line.
Back-Up Light SwitchOn left side of transmission.
Clutch SwitchOn bracket, above clutch pedal. See Fig. 2 .
Neutral SwitchOn right rear side of transmission. See Fig. 2 .
Parking Brake SwitchOn base of parking brake lever.
Power Steering Pressure SwitchOn power steering housing assembly. See Fig. 2 .
Seat Belt Buckle SwitchOn driver's side seat belt buckle.
Stoplight SwitchOn bracket, above brake pedal. See Fig. 2 .
ComponentLocation
Diagnostic Check ConnectorOn left rear of engine compartment, near master cylinder. See Fig. 2 .
IgniterOn right rear corner of engine compartment, near fuse/relay block. See
Fig. 2
.
SRS Back-Up BatteryMounted below SRS control unit. See Fig. 3 .
NOTE: Figures may show multiple component locations. Refer to appropriate table for
proper figure references.

1991 Mazda MX-5 Miata
ELECTRICAL COMPONENT LOCATOR 1991 MAZDA ELECTRICAL COMPONENTS
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Fig. 1: Component Locations (1 Of 3)

1991 Mazda MX-5 Miata
ELECTRICAL COMPONENT LOCATOR 1991 MAZDA ELECTRICAL COMPONENTS
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Fig. 2: Component Locations (2 Of 3)

1991 Mazda MX-5 Miata
ELECTRICAL COMPONENT LOCATOR 1991 MAZDA ELECTRICAL COMPONENTS
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Sunday, July 05, 2009 2:15:23 PMPage 5 © 2005 Mitchell Repair Information Company, LLC.

Fig. 3: Component Locations (3 Of 3)

1991 Mazda MX-5 Miata
ELECTRICAL COMPONENT LOCATOR 1991 MAZDA ELECTRICAL COMPONENTS
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ANTI-LOCK BRAKE SYSTEM
The anti-lock brake system contains electronic equipment that can be susceptible to interference caused by
improperly installed or high output radio transmitting equipment. Since this interference could cause the
possible loss of the anti-lock braking capability, such equipment should be installed by qualified professionals.
On models equipped with anti-lock brake systems, ALWAYS observe the following cautions:
DO NOT attempt to bleed hydraulic system without first referring to the appropriate ANTI-LOCK
BRAKE SYSTEM article in the BRAKES Section.
DO NOT mix tire sizes. As long as tires remain close to the original diameter, increasing the width is
acceptable. Rolling diameter must be identical for all 4 tires. Some manufacturers recommend tires of the
same brand, style and type. Failure to follow this precaution may cause inaccurate wheel speed readings.
Use ONLY recommended brake fluids. DO NOT use silicone brake fluids in an ABS-equipped vehicle.
BATTERY WARNING
REPLACING BLOWN FUSES
Before replacing a blown fuse, remove ignition key, turn off all lights and accessories to avoid damaging the
electrical system. Be sure to use fuse with the correct indicated amperage rating. The use of an incorrect
amperage rating fuse may result in a dangerous electrical system overload.
BRAKE PAD WEAR INDICATOR
Indicator will cause a squealing or scraping noise, warning that brake pads need replacement.
CATALYTIC CONVERTER
Continued operation of vehicle with a severe malfunction could cause converter to overheat, resulting in
possible damage to converter and vehicle. service.
WARNING:R-134a service equipment or vehicle A/C systems SHOULD NOT be
pressure tested or leak tested with compressed air. Some mixtures of
air/R134a have shown to be combustible at elevated pressures. These
mixtures are dangerous and may cause fire and/or explosions. See AIR
CONDITIONING SERVICE article in GENERAL INFORMATION section.
WARNING: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 GENERAL
INFORMATION section.

1991 Mazda MX-5 Miata
FUSES & CIRCUIT BREAKERS Fuses & Circuit Breakers 1990-95 Mazda
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Any modification to the exhaust system on turbo models, which reduces exhaust backpressure, will lead to lean
fuel mixtures and excessive spark advance. This could cause serious engine damage.
ELECTROSTATIC DISCHARGE SENSITIVE (ESD) PARTS
ENGINE OIL
FUEL SYSTEM SERVICE
HALOGEN BULBS
Halogen bulbs contain pressurized gas which may explode if overheated. DO NOT touch glass portion of bulb
with bare hands. Eye protection should be worn when handling or working around halogen bulbs.
HEADLIGHT RETRACTOR
RADIATOR CAP
RADIATOR FAN WARNING:Many solid state electrical components can be damaged by static
electricity (ESD). Some will display a warning label, but many will not.
Discharge personal static electricity by touching a metal ground point on
the vehicle prior to servicing any ESD sensitive component.
CAUTION: Never use non-detergent or straight mineral oil.
WARNING:Relieve fuel system pressure prior to servicing any fuel system
component (fuel injection models).
CAUTION: If headlight retractor freezes during cold weather operation, DO NOT
attempt to force mechanism. Headlights should be kept raised at all times
in cold weather. To raise them, use only headlight retractor switch. DO
NOT use headlight switch.
CAUTION: Always disconnect the fan motor when working near the radiator fan. The
fan is temperature controlled and could start at any time even when the
ignition key is in the OFF position. DO NOT loosen or remove radiator cap
when cooling system is hot.
WARNING:Keep hands away from radiator fan. Fan is controlled by a thermostatic
switch which may come on or run for up to 15 minutes even after engine
is turned off.

1991 Mazda MX-5 Miata
FUSES & CIRCUIT BREAKERS Fuses & Circuit Breakers 1990-95 Mazda
Microsoft
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A/C-HEATER SYSTEM - MANUAL
1990-92 Manual A/C-Heater Systems
A/C SYSTEM SPECIFICATIONS
A/C SYSTEM SPECIFICATIONS
DESCRIPTION
Blower case, mounted under right end of instrument panel, contains blower motor and fresh/recirculated air
door. Evaporator case, to left of blower case, contains evaporator, evaporator thermoswitch and expansion
valve. Heater case, to left of evaporator case, contains airflow mode door and air-mix (temperature blend) door.
ELECTRICAL COMPONENT LOCATIONS
OPERATION
All air control doors are controlled manually by cable from control panel. Top lever controls the air-mix door,
center lever controls the fresh/recirculated air door and bottom lever controls the airflow mode door.
ApplicationSpecification
Compressor TypeNippondenso Rotary Vane
Compressor Belt Deflection (1) (2)
New5/16-23/64" (8-9 mm)
Used23/64-25/64" (9-10 mm)
Compressor Oil Capacity2.7-3.3 oz.
Refrigerant (R-12) Capacity28 oz.
System Operating Pressures
High Side171-235 psi (12.0-16.5
kg/cm
2 )
Low Side21-43 psi (1.5-3.0 kg/cm2 )
(1)With 22 lbs. (10 kg) pressure applied to center of belt.
(2)On vehicles with P/S, measure midway between crankshaft pulley and P/S pump pulley. On vehicles
without P/S, measure midway between crankshaft pulley and A/C idler pulley.
ComponentLocation
A/C RelayIn Right Front Corner Of Engine Compartment
Blower Motor RelayIn Left Rear Corner Of Engine Compartment
Blower ResistorOn Bottom Of Blower Case
Evaporator Thermoswitch. On Left Side Of Evaporator Case
Pressure SwitchIn High-Pressure Line, Between Receiver-Drier
And Evaporator

1991 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1990-92 Manual A/C-Heater Systems

1991 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1990-92 Manual A/C-Heater Systems
Microsoft
Sunday, July 05, 2009 2:11:52 PMPage 1 © 2005 Mitchell Repair Information Company, LLC.
Microsoft
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