1997 MAZDA MX-5 brake light

ANTI-LOCK BRAKE SYSTEM
1997 BRAKES Mazda - Anti-Lock
DESCRIPTION
The Anti-Lock Brake System (ABS) control module senses reductions in front and rear wheel speed and
modulates hydraulic pressure to the brakes to prevent wheel lock-up. The ABS consists of a hydraulic unit, 4
wheel speed sensors and sensor rotors, valve relay, motor relay, pump motor and ABS control module. An ABS
warning light is located on the instrument cluster.
OPERATION
Under normal driving conditions, Anti-Lock Brake System (ABS) functions like a standard brake system. When
vehicle speed reaches 3.8 MPH, ABS will diagnose pump motor by briefly operating motor. Pump motor
operation may be heard inside vehicle.
ABS control module controls ABS by detecting speed sensor signals and activating solenoid valve in hydraulic
unit. Control module also controls pump motor and self-diagnostic function. If a problem is detected in ABS,
ABS will function like a conventional brake system. ABS 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.
COMPONENT LOCATIONS
COMPONENT LOCATIONS CAUTION: See ANTI
-LOCK BRAKE SAFETY PRECAUTIONS article in GENERAL
INFORMATION.
NOTE: For more information on brake system, see BRAKE SYSTEM article.
ApplicationLocation
ABS Control ModuleUnder Carpet, Behind Passenger Seat
Data Link ConnectorLeft Side Of Engine Compartment
Front Sensor RotorOn Front Wheel Hub
Hydraulic UnitRight Rear Of Engine Compartment
Motor & Valve RelaysOn Hydraulic Unit
Pump MotorOn Hydraulic Unit
Rear Sensor RotorOn Rear Drive Axle
Wheel Speed SensorOn Knuckle

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
Microsoft
Sunday, July 05, 2009 1:48:48 PMPage 1 © 2005 Mitchell Repair Information Company, LLC.
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Sunday, July 05, 2009 1:48:54 PMPage 1 © 2005 Mitchell Repair Information Company, LLC.

BLEEDING BRAKE SYSTEM
1. Raise and support vehicle. Ensure brake fluid reservoir remains at least half full during bleeding
procedure. When bleeding brake system, start with longest brakeline first. Remove bleed screw cap.
Connect one end of transparent vinyl tube to bleed screw. Submerge other end of tube in a container half
filled with clean brake fluid.
2. Have an assistant depress brake pedal several times and hold in depressed position. Loosen bleed screw
and drain fluid into container. Tighten bleed screw.
3. Refill brake fluid reservoir if necessary. Repeat step 2) until air is no longer discharged. Tighten bleed
screw to 52-78 INCH lbs. (5.9-8.8 N.m). Ensure fluid leakage is not present. Add fluid to reservoir.
Repeat procedure for remaining wheels.
TROUBLE SHOOTING
Before attempting to diagnose vehicle, ensure ABS warning light is functioning properly. ABS warning light
will not illuminate and ABS will not operate if battery voltage is insufficient. Perform trouble shooting
procedures on ABS warning light to eliminate unnecessary repairs and/or component replacement.
ABS WARNING LIGHT DOES NOT ILLUMINATE WHEN IGNITION IS TURNED ON
1. Turn ignition on. Check if other warning lights illuminate. If other warning lights do not illuminate, check
METER fuse. Replace as necessary. If other warning lights illuminate, check for possible malfunction
and repair as necessary. Go to next step.
2. Turn ignition off. Disconnect ABS Control Module (ABS CM) connector. See COMPONENT
LOCATIONS . Turn ignition on. Check if ABS warning light illuminates. If ABS warning light
illuminates, go to next step. If ABS warning light does not illuminate, go to step 5).
3. Reconnect ABS CM connector. Turn ignition on. Check if ABS warning light illuminates. If ABS
warning light does not illuminate, go to next step. If ABS warning light illuminates, a temporary poor
contact in wiring may have occurred and ABS is now functioning properly.
4. Check if terminal AD of ABS CM harness connector is damaged or deformed. See Fig. 3
. If terminal AD
is damaged or deformed, replace wiring harness connector. If terminal AD is okay, replace ABS CM.
5. With ABS CM connector disconnected, use a jumper wire and ground terminal AD of ABS CM harness
connector. Check if ABS warning light illuminates. If ABS warning light illuminates, go to next step. If
ABS warning light does not illuminate, go to step 7).
6. With ABS CM disconnected, check continuity between terminal AB of ABS CM harness connector and
ground. Also, check continuity between terminal AC of ABS CM harness connector and ground, and CAUTION: DO NOT allow reservoir to run dry during brake bleeding procedure. If
brake fluid is spilled, clean surface immediately with alcohol, as brake
fluid will damage painted surfaces. Use only DOT 3 brake fluid and DO
NOT mix with any other types.
NOTE: Ensure brake pedal remains depressed until bleed screw is tightened.

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
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between terminal AM of ABS CM harness connector and ground. If continuity exists, replace wiring
harness connector. If continuity does not exist, repair wiring harness.
7. Check ABS warning light bulb. Replace bulb as necessary. If bulb is okay, go to next step.
8. Check continuity between terminal AD of ABS CM harness connector and terminal 1K of instrument
cluster connector. See WIRING DIAGRAMS
. If continuity exists, check ABS warning light. See ABS
WARNING LIGHT under COMPONENT TESTING
. If continuity does not exist, repair wiring
harness.
ABS WARNING LIGHT REMAINS ILLUMINATED
1. Ensure battery is fully charged. Charge or replace as necessary. If battery is fully charged, go to next step.
2. Check ABS Control Module (ABS CM) connector for poor connection. Turn ignition on. Check if ABS
warning light goes out. If ABS warning light does not go out, go to next step. If ABS warning light goes
out, a temporary poor contact in wiring may have occurred and ABS is now functioning properly.
3. Turn ignition off. Disconnect ABS CM connector. See COMPONENT LOCATIONS
. Measure voltage
between terminals "A" and AB of ABS CM harness connector. See Fig. 3
. Also, measure voltage
between terminals "A" and AC of ABS CM harness connector, and between terminals "A" and AM of
ABS CM harness connector. If battery voltage is present, go to next step. If battery voltage is not present,
repair wiring harness.
4. Connect ABS CM connector. Check for ABS DTCs. See RETRIEVING DIAGNOSTIC TROUBLE
CODES under DIAGNOSIS & TESTING. If no DTCs are present, go to next step.
5. Turn ignition off. Disconnect ABS CM connector. Connect Harness Adapter (49-F066-022). Turn
ignition on. Check if ABS warning light goes out. If ABS warning light does not go out, repair short in
ABS warning light drive harness or instrument cluster. If ABS warning light goes out, replace ABS CM.
ABS WARNING LIGHT FLASHES WITH VEHICLE STOPPED
1. Ensure battery is fully charged. Charge or replace as necessary. If battery is fully charged, go to next step.
2. Check if a jumper wire is installed between terminals TBS and GND of Data Link Connector (DLC). See
Fig. 1
. If jumper wire is installed, remove jumper wire from DLC. If jumper wire is not installed, go to
next step.
3. Turn ignition off. Disconnect ABS Control Module (ABS CM) connector. See COMPONENT
LOCATIONS . Check continuity between terminal "P" of ABS CM harness connector and ground. See
Fig. 3
. If continuity exists, repair short to ground in DLC wiring harness. If continuity does not exist,
replace ABS CM. NOTE: ABS warning light will illuminate if voltage between terminal "A" (voltage
supply) of ABS CM harness connector and ground is less than about 10
volts.

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
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Fig. 1: Identifying Data Link Connector (DLC) Terminals
Courtesy of MAZDA MOTORS CORP.
ABS WARNING LIGHT REMAINS ILLUMINATED DURING DRIVING UNTIL IGNITION IS
TURNED OFF
1. Check for ABS DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES
under DIAGNOSIS &
TESTING. If no DTCs are present, go to next step.
2. Check ABS Control Module (ABS CM) connector for poor connection. Drive vehicle and recheck ABS
warning light. If ABS warning light remains illuminated during driving and goes out when ignition is
turned off, replace ABS CM. If ABS warning light does not remain illuminated during driving, a
temporary poor contact in wiring may have occurred and ABS is now functioning properly.
ABS WARNING LIGHT ILLUMINATES/GOES OUT WITH VEHICLE STOPPED AND DURING
DRIVING
1. Check for ABS DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES
under DIAGNOSIS &
TESTING. If no DTCs are present, go to next step.
2. Turn ignition off. Disconnect ABC Control Module (ABS CM) connector. See COMPONENT
LOCATIONS . Turn ignition on. Check if ABS warning light illuminates. If ABS warning light
illuminates, go to next step. If ABS warning light does not illuminate, repair ABS warning light wiring
harness or instrument cluster.

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
Microsoft
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3. Turn ignition off. Disconnect ABS CM connector. Measure voltage between terminals "A" and AB of
ABS CM harness connector. See Fig. 3
. Also, measure voltage between terminals "A" and AC of ABS
CM ha rness connector, and between terminals "A" and AM of ABS CM harness connector. If battery
voltage is present, go to next step. If battery voltage is not present, repair wiring harness.
4. Turn ignition off. Reconnect ABS CM connector. Drive vehicle and recheck ABS warning light. If ABS
warning light illuminates/goes out with vehicle stopped and during driving, replace ABS CM. If ABS
warning light does not illuminate/go out with vehicle stopped and during driving, a temporary poor
contact in wiring may have occurred and ABS is now functioning properly.
ABS WARNING LIGHT INDICATES NORMAL, BUT ABS DOES NOT OPERATE PROPERLY
Check for ABS DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES
under DIAGNOSIS &
TESTING. If no DTCs are present, inspect mechanical system.
PRE-DIAGNOSIS INSPECTION
Visually inspect ABS components for possible cause of anti-lock problem. Visual inspection may help identify
cause of a simple malfunction. Ensure ABS warning light is functioning properly. See TROUBLE
SHOOTING .
ABS warning light illuminates under the following conditions:
Vehicle operated on snow or ice with parking brake activated, or a dragging brake at one wheel.
Different size tires being used.
Tires with different traction characteristics are used on same axle.
Vehicle is jacked up and drive wheels spin for 20 seconds or more with ignition on.
Low battery voltage.
If ABS warning light illuminates because of these conditions, turn ignition off, then back on. ABS warning light
will go out and no DTCs for described conditions will be stored in ABS control module memory.
DIAGNOSIS & TESTING
Diagnose ABS using New Generation Star (NGS) Tool (49-T088-0A0) and Adapter Harness (49-F066-002).
See RETRIEVING DIAGNOSTIC TROUBLE CODES
. On all models, test ABS control module using
DVOM and adapter harness. See ABS CONTROL MODULE under COMPONENT TESTING
.
If ABS test equipment is unavailable, test each component of ABS. See COMPONENT TESTING
. If all
ABS components test okay, replace ABS control module with a known-good module and retest system.
RETRIEVING DIAGNOSTIC TROUBLE CODES
Using New Generation Star (NGS) Tool
1. Turn ignition off. Connect New Generation Star (NGS) Tool (49-T088-0A0) to Data Link Connector

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
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(DLC). Set NGS Adapter (49-T088-003) to ABS. Select VEHICLE & ENGINE SELECTION, then select
vehicle model, engine type and model year. Select DIAGNOSTIC DATA LINK. Select ABS-ANTI
LOCK BRAKE MODULE.
2. Select DIAGNOSTIC TEST MODE and note any codes displayed. See DIAGNOSTIC TROUBLE
CODE DESCRIPTION table. Perform appropriate test. See DIAGNOSTIC TROUBLE CODE (DTC)
TESTING . Clear codes after servicing. See CLEARING CODES .
DIAGNOSTIC TROUBLE CODE DESCRIPTION
DTCProbable Cause
05 Stoplight Switch Wiring Harness
11 Right Front Wheel Speed Sensor/Sensor Rotor
12 Left Front Wheel Speed Sensor/Sensor Rotor
13 Right Rear Wheel Speed Sensor/Sensor Rotor
14 Left Rear Wheel Speed Sensor/Sensor Rotor
15 Wheel Speed Sensor/Sensor Rotor
22 (1) Right Front Solenoid Valve (AV)
23 (2) Right Front Solenoid Valve (EV)
24 (1) Left Front Solenoid Valve (AV)
25 (2) Left Front Solenoid Valve (EV)
26 (1) Rear Solenoid Valve (AV)
27 (2) Rear Solenoid Valve (EV)
51 Valve Relay
53 Motor Relay/Pump Motor
61 ABS Control Module
(1)Pressure retention valve.
(2)Pressure reduction valve.

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
Microsoft
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Fig. 2: Reading Diagnostic Trouble Code Output
Courtesy of MAZDA MOTORS CORP.
CLEARING CODES
1. Turn ignition off. Connect a jumper wire between TBS terminal and GND terminal of Data Link
Connector (DLC). See Fig. 1
. Turn ignition on. Output all diagnostic trouble codes stored in ABS control
module memory. When first code is repeated, depress brake pedal 10 times at intervals of less than one
second.
2. When codes are cleared, ABS warning light will illuminate for 3 seconds, then go out. ABS operation
should return to normal control. If ABS warning light does not operate as described and ABS does not
return to normal operation, repeat procedure ensuring brake pedal interval does not exceed one second.
DIAGNOSTIC TROUBLE CODE (DTC) TESTING
* PLEASE READ FIRST *
NOTE: Disconnecting battery does not clear Diagnostic Trouble Codes (DTCs). If DTCs
will not clear, ensure stoplight switch is functioning properly.
NOTE: See PRE
-DIAGNOSIS INSPECTION and DIAGNOSIS & TESTING before
proceeding with DIAGNOSTIC TROUBLE CODE (DTC) TESTING. After repairs
are complete, clear DTCs from ABS control module memory. See CLEARING
CODES under DIAGNOSIS & TESTING.

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
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DTC 05: STOPLIGHT SWITCH WIRING HARNESS
1. Check stoplight switch wiring harness for open or short to ground between stoplight switch and ABS
control module. See WIRING DIAGRAMS
. Repair as necessary. If wiring harness is okay, go to next
step.
2. Clear DTCs. See CLEARING CODES under DIAGNOSIS & TESTING. Recheck for DTCs. If DTC 05
is displayed, replace ABS control module. If DTC 05 is not displayed, a temporary poor contact in wiring
may have occurred and ABS is now functioning properly.
DTCS 11, 12, 13 & 14: WHEEL SPEED SENSOR, SENSOR ROTOR, HYDRAULIC UNIT OR
WIRING HARNESS
1. Check ABS control module connector for poor connection. See COMPONENT LOCATIONS
. Repair
as necessary. If connector is okay, go to next step.
2. Check wiring harness for open or short to ground between suspect wheel speed sensor and ABS control
module. See WIRING DIAGRAMS
. Repair as necessary. If wiring harness is okay, go to next step.
3. Check suspect wheel speed sensor. See WHEEL SPEED SENSORS under COMPONENT TESTING
.
Replace as necessary. If wheel speed sensor is okay, go to next step.
4. Inspect wheel speed sensor rotor for damage or missing teeth. If sensor rotor is damaged or has missing
teeth, replace sensor rotor. If sensor rotor is okay, go to next step.
5. Inspect brakeline for damage. If brakeline is damaged, replace brakeline. If brakeline is okay, go to next
step.
6. Check hydraulic unit. See HYDRAULIC UNIT under COMPONENT TESTING
. Replace as
necessary. If hydraulic unit is okay, go to next step.
7. Clear DTCs. See CLEARING CODES
under DIAGNOSIS & TESTING. Recheck for DTCs after
driving vehicle from a stop to faster than 6.2 MPH. If DTC 11, 12, 13 or 14 is displayed, replace ABS
control module. If DTC 11, 12, 13 or 14 is not displayed, a temporary poor contact in wiring may have
occurred and ABS is now functioning properly.
DTC 15: WHEEL SPEED SENSOR, SENSOR ROTOR, HYDRAULIC UNIT OR WIRING HARNESS
If DTC 15 is displayed, perform DTCS 11
, 12, 13 & 14: WHEEL SPEED SENSOR, SENSOR ROTOR,
HYDRAULIC UNIT OR WIRING HARNESS test.
DTCS 22, 23, 24, 25, 26 & 27: SOLENOID VALVE OR WIRING HARNESS
1. Check ABS control module connector for poor connection. See COMPONENT LOCATIONS
. Repair
as necessary. If connection is okay, go to next step.
2. Check suspect solenoid valve with valve relay installed. See SOLENOID VALVES
under
COMPONENT TESTING. Replace as necessary. If solenoid valve with valve relay installed is okay, go
to next step.
3. Check suspect solenoid valve with valve relay removed. See SOLENOID VALVES
under
COMPONENT TESTING. Replace solenoid valve as necessary. If solenoid valve with valve relay
removed is oka
y, go to next step.

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
Microsoft
Sunday, July 05, 2009 1:48:48 PMPage 8 © 2005 Mitchell Repair Information Company, LLC.