check engine MAZDA MIATA 1991 Factory User Guide

Fig. 7: Identifying Drive Belt Routing & Deflection Check Point (3 Of 3)
Courtesy of MAZDA MOTORS CORP.
ADJUSTMENT SPECIFICATIONS
DEFLECTION SPECIFICATIONS
NOTE: Check belt deflection when engine is cold, or has bin off for 30 minutes.
Application(1) Specification - In. (mm)
New Belt (2)
Alternator0.31-0.35 (8-9)
A/C Compressor0.31-0.35 (8-9)
Power Steering Pump0.31-0.35 (8-9)
Used Belt
Alternator0.35-0.39 (9-10)
A/C Compressor0.35-0.39 (9-10)
Power Steering Pump0.35-0.39 (9-10)
(1)Deflection with 22 lbs. (10 kg) pressure applied midway on belt run.
Used on for less than 5 minutes.

1991 Mazda MX-5 Miata
1990-93 ENGINE COOLING Drive Belt Routing & Adjustment - MX-5 Miata
Microsoft
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ELECTRICAL COMPONENT LOCATOR
1991 MAZDA ELECTRICAL COMPONENTS
BUZZERS, RELAYS & TIMERS
BUZZERS, RELAYS & TIMERS LOCATION
CIRCUIT PROTECTION DEVICES
CIRCUIT PROTECTION DEVICES LOCATION
CONTROL UNITS
ComponentLocation
ABS System
Check Valve RelayOn top of ABS pump motor.
Motor RelayOn top of ABS pump motor.
Buzzer & Timer UnitOn bracket, behind left side of dash.
See Fig. 1
.
Circuit Opening RelayOn bracket, behind left side of dash.
See Fig. 1
.
Cooling Fan RelayIn engine compartment fuse/relay
block. See Fig. 1
.
Dashboard Illumination Lights RelayOn bracket, near master cylinder. See
Fig. 1
.
EFI Main RelayIn engine compartment fuse/relay
block. See Fig. 1
& Fig. 2 .
Fuel Pump RelayBehind left front kick panel.
Headlight RelayOn bracket, near master cylinder. See
Fig. 1
.
Headlight Retractor RelayOn bracket, near master cylinder. See
Fig. 1
.
Horn RelayOn bracket, behind left side of dash.
See Fig. 1
.
Ignition RelayIn engine compartment fuse/relay
block.
Turn Signal/Hazard Flasher RelayOn bracket, behind left side of dash.
See Fig. 1
.
ComponentLocation
Fuse BlockBehind left side of dash.
Fuse/Relay BlockIn right rear corner of engine compartment, near firewall.
See Fig. 2
.
Heater Blower Motor Circuit BreakerIn passenger compartment fuse block.

1991 Mazda MX-5 Miata
ELECTRICAL COMPONENT LOCATOR 1991 MAZDA ELECTRICAL COMPONENTS

1991 Mazda MX-5 Miata
ELECTRICAL COMPONENT LOCATOR 1991 MAZDA ELECTRICAL COMPONENTS
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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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LOWER CONTROL ARM
Removal
Raise and support vehicle. Remove wheel assembly. Remove engine splash shield (if equipped). Remove
stabilizer bar from lower control arm. Remove strut rod (if equipped). Remove ball joint clamp bolt or pivot
nut, and separate ball joint from steering knuckle. Remove lower control arm pivot bolts. Remove lower control
arm.
Inspection
Check lower control arm for damage or cracks. Check bushings for deterioration and excessive wear. Check
ball joint for excessive wear. Examine dust boot for damage. Replace parts as necessary.
Bushing Replacement (Miata)
Cut or press old bushing from control arm. Coat new bushing with paraffin-based oil. Press new bushing into
control arm. To install, reverse removal procedure.
Bushing Replacement (MPV 4WD)
Cut away bushing inner collar. Using a vise and Remover/Installer (49-G033-102 and 49-FO27-009), push out
front bushing. Press out rear bushing using a press and Remover/Installer (49-U034-202 and 49-GO26-103). To
install front bushing, apply soapy water to bushing and use remover/installer to press in. To install rear bushing,
align arrows on bushing with marks on lower arm and use remover/installer to press in.
Bushing Replacement (MX-6 & 626)
Cut away bushing inner collar. Using a vise and Remover/Installer (49-GO34-2A0), push out bushing. To
install, apply soapy water to bushing and use remover/installer to press in. Always install bushing from outer
side of arm. Press in bushing until collar contacts arm.
Bushing Replacement (Protege & 323)
Using a vise and Remover/Installer Set (49-BO34-2A0), push out bushing. To install, apply soapy water to
bushing and use remover/installer to press in. Always install bushing from outer side of arm. Press in bushing
until collar contacts arm.
Bushing Replacement (929)
Cut away bushing outer collar. Using a vise and Remover/Installer (49-HO34-202 and 49-HO34-201), remove
bushing from control arm. To install, reverse removal procedure.
Bushing Replacement (RX7)
NOTE: Lower control arm bushings are not replaceable on MPV 2WD models. Replace
control arm assembly if bushings are worn or damaged.

1991 Mazda MX-5 Miata
SUSPENSION - FRONT 1990-91 SUSPENSION Front
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Push out front bushing using a press and Remover (49-G030-627A). To remove rear bushing, install Bearing
Puller (49-0710-520) on bushing. DO NOT overtighten bearing puller nuts or lower arm will be distorted and
damaged. Press to push out rear bushing using Remover (49-G030-627A). To install both bushings, use
remover and Support Block (49-0823-146).
Installation (All Models)
To install, reverse removal procedure. Tighten lower control arm pivot bolts to specification with vehicle
resting on ground and suspension unloaded. See TORQUE SPECIFICATIONS
.
UPPER CONTROL ARM
Removal (Miata)
Raise and support vehicle. Remove wheel assembly. Remove engine splash shield. Remove ball joint pivot nut.
Use Puller (49-0118-850C) to separate ball joint from steering knuckle. Remove upper control arm pivot bolts.
Remove upper control arm.
Inspection
Check upper control arm for damage or cracks. Check bushings for deterioration and excessive wear. Check
ball joint for excessive wear. Examine dust boot for damage. Replace parts as necessary.
Bushing Replacement
Using a chisel, remove old bushing from control arm. Coat new bushing with grease. Press new bushing into
control arm.
Installation
To install, reverse removal procedure. Tighten upper control arm pivot bolts to specification with vehicle
resting on ground and suspension unloaded.
SHOCK ABSORBER
Removal (Miata)
Raise and support vehicle. Remove wheel assembly. Remove engine splash shield. Remove stabilizer link bolt.
Separate upper ball joint from steering knuckle. Loosen lower control arm pivot bolts. Remove shock absorber
upper mount nuts and lower bolt. Move lower control arm just enough to remove shock absorber. Be careful not
to damage brake line.
Disassembly
Clamp upper mount in vise. Loosen lock nut 2 turns only. Compress coil spring using coil spring compressor.
Remove lock nut and remainin
g components. Slowly release compressor tension.

1991 Mazda MX-5 Miata
SUSPENSION - FRONT 1990-91 SUSPENSION Front
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Blower motor relay supplies power to blower motor. Blower resistor determines blower speed. With blower
switch in highest position, blower motor is grounded through blower switch. With blower switch in all other
positions, blower motor is grounded through blower resistor and blower switch.
Circuit through compressor clutch is completed when A/C relay is energized and pressure switch is closed. A/C
relay is energized when Engine Control Unit (ECU) unit grounds the solenoid circuit of the relay. The ECU
energizes A/C relay if evaporator thermoswitch is closed and A/C and blower switches are on. The ECU also
controls A/C relay operation according to engine load.
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
AIR BAG WARNING
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. 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
A/C-HEATER SYSTEM - MANUAL 1990-92 Manual A/C-Heater Systems
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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 voltage is present, replace blower resistor. If battery voltage is present, check voltage at Blue/Red
wire terminal of blower resistor 4-wire connector. If no voltage is present, replace blower resistor.
5. If battery voltage is present, check voltage at Blue/Green wire terminal of blower resistor connector. If no
voltage is present, replace blower resistor. If battery voltage is present, check voltage at Blue/Yellow wire
terminal of blower resistor connector.
6. If no voltage is present, replace blower resistor. If battery voltage is present, turn ignition on and blower
switch to 4th position (high). Check voltage at Black wire terminal of blower switch connector. If battery
voltage is present, repair wiring between blower switch and ground.
7. If no voltage is present, turn ignition switch, blower switch and A/C switch off. Check voltage at
Blue/White wire terminal of blower switch connector. If no voltage is present, repair wiring between
blower resistor and blower switch.
8. If battery voltage is present, check voltage at Blue/Red wire terminal of blower switch connector. If no
voltage is present, repair wiring between blower resistor and blower switch. If battery voltage is present,
check voltage at Blue/Green wire terminal of blower switch connector.
9. If no voltage is present, repair wiring between blower resistor and blower switch. If battery voltage is
present, check voltage at Blue/Yellow wire terminal of blower switch connector. If battery voltage is
present, replace blower switch. If no voltage is present, repair wiring between blower resistor and blower
switch.
COMPRESSOR CLUTCH CIRCUIT
1. Turn ignition on. Check 20-amp WIPER fuse in passenger compartment fuse block. Check 20-amp AD
FAN (additional fan) fuse in engine compartment fuse block. If fuses are blown, repair short circuit.
2. If fuses are okay, run engine at idle. Turn A/C and blower switches on. Check voltage at compressor
clutch connector (Black/Red wire terminal). If no voltage is present, go to step 5).
3. If battery voltage is present, turn ignition off. Disconnect evaporator thermoswitch connector. Check
continuity between switch terminals. If there is no continuity, replace evaporator thermoswitch.
4. If there is continuity, disconnect compressor clutch connector. Set ohmmeter to X1000 scale. Check
continuity between compressor clutch connector and ground. If there is no continuity, replace compressor
clutch. If there is continuity, adjust compressor clutch air gap or check compressor for internal damage.
5. Run engine at idle. Turn A/C and blower switches on. Check voltage at Black/Blue wire terminal of A/C
relay connector. If battery voltage is present, go to step 9).
6. If no voltage is present, check voltage at Blue/Yellow wire terminal of A/C relay connector. If no voltage
is present, repair circuit between 20-amp AD FAN fuse and A/C relay.
7. If battery voltage is present, check voltage at Blue wire terminal of A/C relay connector. If no voltage is
present, repair circuit between 20-amp WIPER fuse and A/C rela
y. 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
A/C-HEATER SYSTEM - MANUAL 1990-92 Manual A/C-Heater Systems
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8. If battery voltage is present, check voltage at Blue/Black wire terminal of A/C relay connector. If no
voltage is present, replace A/C relay. If battery voltage is present, check Engine Control Unit (ECU)
terminal voltage.
9. Turn ignition off. Disconnect pressure switch connector. Check continuity between switch terminals. If
there is continuity, repair circuit between A/C relay and compressor clutch.
10. If there is no continuity, connect manifold pressure gauges to system. If low pressure is 21-43 psi (1.5-3.0
kg/cm
2 ) and high pressure is 171-235 psi (12.0-16.5 kg/cm2 ), replace pressure switch. If pressures are
not as specified, check refrigerant system for proper charge.
CONDENSER (ADDITIONAL) FAN CIRCUIT
1. Turn ignition on. Turn A/C and blower switches on. Check voltage at Black/Blue wire terminal of
condenser fan connector. If no voltage is present, repair circuit between A/C relay and condenser fan.
2. If battery voltage is present, check voltage at Black wire terminal of condenser fan connector. If no
voltage is present, replace condenser fan motor. If battery voltage is present, repair circuit between
condenser fan and ground.
A/C & BLOWER SWITCH
With switches in positions indicated, check continuity between specified terminals of A/C and blower switch
connector. See Fig. 1
. If continuity is not as specified, replace A/C and blower switch.

1991 Mazda MX-5 Miata
A/C-HEATER SYSTEM - MANUAL 1990-92 Manual A/C-Heater Systems
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BLOWER MOTOR
Disconnect 2-wire connector from bottom of blower motor case. Apply battery voltage across blower motor
terminals. Replace blower motor if it does not operate.
BLOWER RESISTOR
Note 4-wire connector and 1-wire connector attached to seam where upper and lower blower cases meet. Wires
in these connectors lead to blower resistor on bottom of blower case. Disconnect both connectors. If continuity
does not exist between 1-wire connector terminal and each terminal of 4-wire connector, replace blower
resistor.
CONDENSER (ADDITIONAL) FAN MOTOR
Disconnect condenser fan connector. Apply battery voltage across condenser fan terminals. Replace condenser
fan motor if it does not operate.
EVAPORATOR THERMOSWITCH
1. Remove glove box. Run engine at idle. Turn off A/C switch. Turn blower switch to 4th position (high) for
a few minutes to ensure evaporator temperature is greater than 32°F (0°C). Turn off blower switch and
engine.
2. Disconnect evaporator thermoswitch connector. Check continuity between switch terminals. If there is
continuity, thermoswitch is okay. If there is no continuity, replace thermoswitch.
PRESSURE SWITCH
1. Turn ignition off. Connect manifold pressure gauges to system. If high-side pressure is less than 31.2 psi
(2.2 kg/cm
2 ), check system for proper refrigerant charge.
2. If high-side pressure is greater than 31.2 psi (2.2 kg/cm
2 ), disconnect pressure switch connector. Check
continuity between switch terminals. If there is continuity, switch is okay. If there is no continuity,
replace switch.
REMOVAL & INSTALLATION
AIR BAG WARNING
BLOWER CASE
Removal & Installation
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
A/C-HEATER SYSTEM - MANUAL 1990-92 Manual A/C-Heater Systems
Microsoft
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LUBRICATION
CAPACITY
POWER STEERING FLUID CAPACITY
FLUID TYPE
Dexron-II or M-III are recommended for all vehicles.
FLUID LEVEL CHECK
Check fluid level with engine off. Remove fluid level gauge on oil pump or reservoir. Check fluid level. Fluid
should be between "L" and "H" marks on level gauge dipstick. If fluid level is low, fill through gauge tube.
Recheck fluid level. DO NOT overfill.
HYDRAULIC FLUID BLEEDING
1. Raise and support front of vehicle. With ignition off, turn steering wheel lock-to-lock several times. Add
fluid as necessary. Repeat procedure until fluid level no longer decreases.
2. Start engine and let idle. Turn steering wheel lock-to-lock 5 times. Check fluid level. Add fluid as
necessary. Continue procedure until fluid is clear of air bubbles and does not decrease in level.
ADJUSTMENTS
POWER STEERING BELT ADJUSTMENT
POWER STEERING BELT DEFLECTION
(1)
(1)Specifications are measured at 1000-1500 RPM, with fluid temperature at 122-140°F (50-60°C).
ApplicationQts. (L)
Miata, MPV & 929.95 (.90)
MX-6 & 626
Electronc Controlled Power Steering (ECPS)1.06 (1.0)
Engine Speed (Sensing) Power Steering (ESPS).95 (.90)
Protege & 323.63 (.60)
RX7.85 (.80)
NOTE: On-vehicle adjustment procedures are not available from manufacturer.
ApplicationIn. (mm)
Miata, Protege & 323
New Belt.31-.35 (7.8-8.9)

1991 Mazda MX-5 Miata
STEERING GEAR - POWER RACK & PINION 1991 STEERING Mazda - Power Rack & Pinion
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