Page 155 of 392

OPERATION
Under normal driving conditions, the anti-lock brake system functions as a standard brake system. When
vehicle speed reaches 3.8 MPH, the ABS system will diagnose pump motor by briefly operating motor. Pump
motor operation may be heard inside vehicle.
The Electronic Control Unit (ECU) controls ABS by detecting speed sensor signals and activating solenoid
valve in hydraulic unit. Control unit also controls pump motor and self-diagnostic function. If a problem in the
ABS system is detected, ABS system functions as a conventional brake system. The ANTI-LOCK brake
warning light will also come on.
With detection of wheel lock-up, short pedal pulsations, occurring in rapid succession, will be felt in brake
pedal and steering wheel. Vehicle body may also vibrate slightly. These conditions are normal. Pedal pulsation
will continue until there is no longer a need for anti-lock function or until vehicle is stopped.
ANTI-LOCK BRAKE SAFETY PRECAUTIONS
NEVER open a bleeder valve or loosen a hydraulic line while ABS is pressurized.
NEVER disconnect or reconnect any electrical connectors while ignition is on. Damage to ABS control
unit may result.
DO NOT attempt to bleed hydraulic system without first referring to the appropriate article.
Only use specially designed brake hoses/lines on ABS-equipped vehicles.
DO NOT tap on speed sensor components (sensor, sensor rings). Speed rings must be pressed, NOT
hammered into hubs. Striking these components can cause demagnetization or a loss of polarization,
affecting the accuracy of the speed signal returning to the ABS control unit.
DO NOT mix tire sizes. Increasing the width, as long as tires remain close to the original diameter, 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.
DO NOT contaminate speed sensor components with grease. Only use recommended anti-corrosion
coating.
When speed sensor components have been removed, ALWAYS check sensor-to-ring air gaps when
applicable. These specifications can be found in each appropriate article.
ONLY use recommended brake fluids. DO NOT use silicone brake fluids in an ABS-equipped vehicle.
When installing transmitting devices (CB's, telephones, etc.) on ABS-equipped vehicles, DO NOT locate
the antenna near the ABS control unit (or any control unit).
Disconnect all on-board computers, when using electric welding equipment. CAUTION: See ANTI-LOCK BRAKE SAFETY PRECAUTIONS below.
WARNING:Refer to appropriate Anti-Lock Brakes (ABS) article for description,
operation, depressurizing, testing, system bleeding, trouble shooting and
system service. Failure to depressurize ABS could lead to physical injury.
1991 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1988-91 BRAKES Mazda Anti-Lock Brake System
Microsoft
Sunday, July 05, 2009 2:17:31 PMPage 3 © 2005 Mitchell Repair Information Company, LLC.
Page 242 of 392

DISC BRAKE SPECIFICATIONS
DISC BRAKE SPECIFICATIONS
Rotor-To-Hub Bolt
B2200 & B2600i40-51 (54-69)
MX-6 & 62636-43 (49-58)
32333-40 (45-54)
Wheel Bearing Lock Nut
B2200 & B2600i (Rear)145-217 (197-295)
323 (Front)116-174 (158-237)
Wheel Lug Nut
B2200 & B2600i
Standard Wheel65-87 (88-118)
Styled Wheel87-108 (118-147)
Navajo85-115 (115-155)
All Others65-87 (88-118)
INCH Lbs. (N.m)
Parking Brake Cable Lock Nut
B2200 & B2600i60-84 (7-10)
All Others168-252 (19-29)
Wheel Cylinder Mounting Bolt
B2200 & B2600i 2WD108-144 (12-16)
B2600i 4WD180-216 (20-24)
Except B2200, B2600i & Navajo (2) 84-108 (10-12)
(1)These bolts secure caliper directly to steering knuckle. On Protege, tighten to 29-36 ft. lbs. (39-49
N.m). On RX7, tighten to 58-72 ft. lbs. (78-98 N.m).
(2)Information is not available from manufacturer for Navajo.
ApplicationIn. (mm)
B2200 & B2600i 2WD Front (1)
Original Thickness.79 (20)
Discard Thickness.71 (18)
B2600i 4WD Front (1)
Original Thickness.87 (22)
Discard Thickness.79 (20)
Miata
Front (2)
Original Thickness.71 (18)
Discard Thickness.63 (16)
1991 Mazda MX-5 Miata
BRAKE SYSTEM 1991 BRAKES Mazda Brake System
Microsoft
Sunday, July 05, 2009 2:18:09 PMPage 39 © 2005 Mitchell Repair Information Company, LLC.
Page 287 of 392
Fig. 3: Adjusting A/C Compressor & Power Steering Pump Belt
Courtesy of MAZDA MOTORS CORP.
1991 Mazda MX-5 Miata
1990-93 ENGINE COOLING Drive Belt Routing & Adjustment - MX-5 Miata
Microsoft
Sunday, July 05, 2009 2:14:16 PMPage 3 © 2005 Mitchell Repair Information Company, LLC.
Page 288 of 392
Fig. 4: Adjusting A/C Compressor Belt
Courtesy of MAZDA MOTORS CORP.
POWER STEERING PUMP
Loosen power steering pump bolt and nuts and adjust belt deflection by turning adjusting bolt. See Fig. 3
, Fig.
6 and Fig. 7 . See ADJUSTMENT SPECIFICATIONS . Tighten bolts to specification. See TORQUE
SPECIFICATIONS .
DRIVE BELT ROUTING
1991 Mazda MX-5 Miata
1990-93 ENGINE COOLING Drive Belt Routing & Adjustment - MX-5 Miata
Microsoft
Sunday, July 05, 2009 2:14:16 PMPage 4 © 2005 Mitchell Repair Information Company, LLC.
Page 291 of 392
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
Sunday, July 05, 2009 2:14:16 PMPage 7 © 2005 Mitchell Repair Information Company, LLC.
Page 292 of 392
TENSION SPECIFICATIONS
TORQUE SPECIFICATIONS
TORQUE SPECIFICATIONS
(2)
Application(1) Specification - Lbs. (kg)
New Belt (2)
Alternator110-132 (50-60)
A/C Compressor110-132 (50-60)
Power Steering Pump110-132 (50-60)
Used Belt
Alternator95-110 (43-50)
A/C Compressor95-110 (43-50)
Power Steering Pump95-110 (43-50)
(1)Measure tension using Tension Gauge (49 9200 020), or equivalent.
(2)Used on for less than 5 minutes.
ApplicationFt. Lbs. (N.m)
Alternator Adjusting Bolt
"A"14-18 (19-25)
"B"27-38 (37-52)
A/C Compressor Locknut27-38 (37-52)
Power Steering Pump Adjusting Bolt
"A"23-44 (31-46)
"B"27-40 (37-54)
"C"14-18 (19-25)
1991 Mazda MX-5 Miata
1990-93 ENGINE COOLING Drive Belt Routing & Adjustment - MX-5 Miata
Microsoft
Sunday, July 05, 2009 2:14:16 PMPage 8 © 2005 Mitchell Repair Information Company, LLC.
Page 295 of 392

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
Microsoft
Sunday, July 05, 2009 2:15:23 PMPage 3 © 2005 Mitchell Repair Information Company, LLC.
Page 299 of 392

SUSPENSION - FRONT
1990-91 SUSPENSION Front
DESCRIPTION
An independent front suspension with MacPherson struts is used on all models except Miata. Miata uses a
double wishbone design with coil over shock absorbers. See Fig. 1
. Strut assemblies mount between steering
knuckle and upper fender panels. Strut assemblies consist of inner shock absorbers and coil springs surrounding
outside of strut tube housing.
The steering knuckle is connected to lower control arm and strut. Lower control arm pivots at crossmember and
is connected by ball joint to steering knuckle. All models are equipped with a stabilizer bar which attaches to
each lower control arm and frame. See Fig. 1
- Fig. 5 . Some models may also be equipped with Auto Adjust
Suspension (AAS). For more information on this system, see ELECTRONIC SUSPENSION article in the
SUSPENSION section.
ADJUSTMENTS & INSPECTION
WHEEL ALIGNMENT SPECIFICATIONS & PROCEDURES
See WHEEL ALIGNMENT SPECIFICATIONS AND PROCEDURES article in the WHEEL ALIGNMENT
section.
WHEEL BEARING
Miata, Protege & 323
Raise and support vehicle. Remove wheel assembly. Remove and wire aside brake caliper. Remove rotor.
Install a dial indicator against wheel hub and measure axial movement. Axial movement should be .002" (.05
mm) maximum. If specification is exceeded, check and adjust lock nut torque or replace bearing on Protege and
323 or hub and bearing assembly on Miata.
MPV & 929
Raise and support vehicle. Remove wheel assembly. Remove and wire aside brake caliper. Install a dial
indicator against wheel hub and measure axial movement. Maximum axial movement should be .002" (.05
mm). If specification is exceeded, check and adjust lock nut torque or replace bearing on MPV 4WD and 929 or
hub and bearing assembly on MPV 2WD.
RX7
1. Raise and support vehicle. Remove wheel assembly. Remove and wire aside brake caliper. Install a dial
indicator against hub and measure axial movement. Axial movement should be zero. If specification is
exceeded, adjust preload or replace wheel bearing.
2. To ad
just preload, remove grease cap, cotter pin and set cover. Loosen lock nut. Tighten to 14-22 ft. lbs.
1991 Mazda MX-5 Miata
SUSPENSION - FRONT 1990-91 SUSPENSION Front
1991 Mazda MX-5 Miata
SUSPENSION - FRONT 1990-91 SUSPENSION Front
Microsoft
Sunday, July 05, 2009 2:08:53 PMPage 1 © 2005 Mitchell Repair Information Company, LLC.
Microsoft
Sunday, July 05, 2009 2:09:01 PMPage 1 © 2005 Mitchell Repair Information Company, LLC.