1991 MAZDA MIATA display

DO NOT expose the ABS control unit to prolonged periods of high heat (185°F/85°C for 2 hours is
generally considered a maximum limit).
BLEEDING BRAKE SYSTEM
For ABS hydraulic unit bleeding, see HYDRAULIC UNIT under REMOVAL & INSTALLATION.
BRAKE LINE BLEEDING SEQUENCE
(1)
DIAGNOSIS
ABS system can only be diagnosed using ABS Tester (0000-42-0010). See Fig. 13 . An Adapter Harness
(49N0-66-001) is also required to test Miata ABS system. ABS tester cannot diagnose ABS control unit. If a
malfunction is detected in ABS and all other components in brake system are okay, replace ABS control unit.
If ABS tester is unavailable, test each component of ABS. See test procedures under TESTING. If all ABS
components test okay, replace control unit with a known good unit, and retest system for correct operation.
PRE-DIAGNOSIS INSPECTION
Perform a visual inspection of ABS components that could cause anti-lock problem. Visual inspection may help
identify cause of simple problem.
DIAGNOSTIC PROCEDURE WITH ABS TESTER
ABS tester uses one display window and 2 switches for reading information from unit. Become thoroughly
familiar with ABS tester displays and operation before proceeding. See Fig. 13
. To diagnose ABS system, go
to TESTING SEQUENCE charts under DIAGNOSING ABS SYSTEM. When diagnosing ABS system,
complete tests in order given under TESTING SEQUENCE. If ABS tester does not operate, check fuses,
ignition switch and ignition circuit.
TESTING
NOTE: See BRAKE BLEEDING article in the BRAKES Section.
ApplicationSequence
Miata & 929Longest Line First
RX7RR, LR, RF, LF
(1)If rear caliper has not been disassembled, open upper bleed valve only.
NOTE: Before testing ABS components, ensure battery and charging system are
functioning properly. To prevent damage to ABS control unit connector, use
very thin pins when probing connector.

1991 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1988-91 BRAKES Mazda Anti-Lock Brake System
Microsoft
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TEST 1. CONNECTION POWER UP
CONNECTION/POWER-UP
1. Locate ABS Control Unit.
2. Disconnect Control Unit Harness from Control Unit.
3. Connect ABS Tester Harness to Control Unit Harness Connector.
4. Turn Ignition Key to "ON" position.
TEST 2 ALTERNATOR TEST
ALTERNATOR TEST START ENGINE (ALTERNATOR TESTED BY RUNNING ENGINE)
Tester will rapidly display several messages during an Initial Segment Check.
Fig. 14: Test 2 Alternator Test

Courtesy of MAZDA MOTORS CORP.
TEST 3 ABS SYSTEM TEST

1991 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1988-91 BRAKES Mazda Anti-Lock Brake System
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ABS SYSTEM TEST TURN IGNITION KEY ON (DO NOT RUN ENGINE
Tester will rapidly display several messages during an Initial Segment Check.
Fig. 15: Test 3 ABS System Test

Courtesy of MAZDA MOTORS CORP.
TEST 4 SYSTEM VOLTAGE TEST

1991 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1988-91 BRAKES Mazda Anti-Lock Brake System
Microsoft
Sunday, July 05, 2009 2:17:32 PMPage 18 © 2005 Mitchell Repair Information Company, LLC.

Courtesy of MAZDA MOTORS CORP.
6A. DYNAMIC WHEEL SELECTION TEST OR EXIT
WHEEL SELECTION TEST
These three messages will alternate on the dispaly screen at 3 1/2 second intervals. Now, select one of the four
wheels to begin the dynamic test sequence.
EXIT
Press either switch under "PUSH TO EXIT" Display to return to "STAT TEST DYNAM" Selection.
NOTE: When entering the dynamic test sequence, you will select one of four wheels to
begin. When you have finished with that wheel test, you should return to 6A.
WHEEL SELECTION TEST to select another wheel, and repeat these test
procedures for all four wheels

1991 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1988-91 BRAKES Mazda Anti-Lock Brake System
Microsoft
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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
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