SYSTEM OPERATION CHECK
Turn ignition on. AIR BAG warning light in instrument cluster should glow for 6 seconds and then turn off. If
AIR BAG warning light does not function as described, a failure has occurred in Supplemental Restraint
System (SRS). Repair malfunctioning SRS. See DIAGNOSIS
. Also, see SERVICE PRECAUTIONS .
SERVICE PRECAUTIONS
The following precautions should be observed when working with air bag systems:
Disable air bag before servicing any air bag system/steering column component. See DISABLING &
ACTIVATING AIR BAG SYSTEM .
Because of critical system operating requirements, DO NOT service any air bag system component or
wiring harness. Corrections are made by replacement only.
DO NOT use an ohmmeter to check resistance of air bag module, as it may cause air bag deployment.
When carrying a live (undeployed) module, ensure trim cover is pointed away from your body. This
minimizes chance of injury in event of accidental air bag deployment.
When placing a live air bag module on any surface, always face trim cover upward to reduce motion of
module if it is accidentally deployed.
SAS unit must always be installed with arrow facing the front of the vehicle.
DO NOT disconnect SAS unit until unit is firmly mounted in vehicle.
Disconnecting or removing SAS unit with ignition switch in ON position can cause accidental
deployment and serious personal injury. Before disconnecting or removing SAS unit connector or
removing SAS unit, turn ignition to LOCK position.
Air bag system clockspring MUST be aligned in neutral position, since its rotation ability is limited. DO
NOT turn steering wheel or column after removal of steering gear.
A double-lock mechanism is used on clockspring connectors. DO NOT use excessive force when
disconnecting connectors, as damage to connector may occur.
ADJUSTMENTS
CLOCKSPRING CENTERING
Turn clockspring clockwise until it stops, then turn clockspring counterclockwise 2.75 turns. Align marks on
clocksprin
g with marks on outer housing. See Fig. 2.
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1. Disable air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM . Remove meter
hood. Ensure instrument cluster 12 pin connector is securely connected and that terminal No. 1 E is not
damaged. Check continuity between terminal No. 1E of 12 pin cluster connector and terminal No. 2K of
print plate of instrument cluster. If there is continuity, go to next step. If there is no continuity, replace
print plate and then go to next step.
2. Disable air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM
. Check if terminal
No. Q of 21 pin SAS unit connector is securely connected and is not damaged. If ok, go to next step. If
terminal Q is not securely connected or is damaged, replace air bag harness, then go to next step.
3. Disconnect 21 pin SAS unit connector and 12 pin instrument cluster connector. Check continuity between
terminal No. Q of SAS unit connector and terminal No. 1 E of instrument cluster connector. If there is
continuity, replace SAS unit and then go to next step. See SAS UNIT
under REMOVAL &
INSTALLATION. If there is no continuity, go to next step.
4. Activate air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM
. Check AIR BAG
warning light for proper system function. See SYSTEM OPERATION CHECK
.
WARNING LIGHT DOES NOT COME ON
Disable air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM
. Remove meter hood.
Ensure instrument cluster 12 pin connector is securely connected and that terminal No. 1 E is not damaged.
Check continuity between terminal No. 1E of 12 pin cluster connector and terminal No. 2K of print plate of
instrument cluster. If there is continuity, go to next step. If there is no continuity, replace print plate and then go
to next step.
WARNING LIGHT REMAINS ON
1. Measure battery voltage. If voltage is more than 9 volts, go to next step. If voltage is not more than 9
volts, check charging system.
2. Disable air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM
. Remove dashboard.
Remove heater unit. Check if SAS unit connector is securely connected. Check short bar between SAS
unit terminal No. Q and terminal No. S. If short bar is bent, replace wiring harness and then go to next
step. If short bar is OK, go to next step.
3. Check short bar hook on SAS unit. If hook is OK, go to next step. If hook is damaged, replace SAS unit.
See SAS UNIT
under REMOVAL & INSTALLATION.
4. Disconnect SAS unit 21 pin connector and instrument panel 12 pin connector. Carefully insert an
insulation material between terminal No. Q and terminal No. S of SAS unit so short bar cannot move. NOTE: For connector terminal identification, see WIRING DIAGRAM
.
NOTE: For connector terminal identification, see WIRING DIAGRAM
.
NOTE: For connector terminal identification, see WIRING DIAGRAM
.
NOTE: Use care not to damage short bar when inserting insulation material.
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5. Check continuity between terminal No. Q and ground. If continuity exists, replace or repair wiring
harness between instrument cluster and SAS unit. If no continuity exists, replace SAS unit. See SAS
UNIT under REMOVAL & INSTALLATION.
6. Activate air bag system and perform SYSTEM OPERATION CHECK
. Check that AIR BAG warning
light is operating properly. If not, reconfirm malfunction symptoms.
DTC 0 - SAS UNIT
1. Disable system. See DISABLING & ACTIVATING AIR BAG SYSTEM
. Remove dashboard.
Remove heater unit. Check if SAS unit connector is securely connected. If not, reconnect connector and
go next step. If ok, go to next step.
2. Disconnect SAS unit connector and check for continuity between terminal No. V and terminal No. Y of
SAS unit connector. If there is continuity, replace SAS unit. If there is no continuity, replace wiring
harness. Perform SYSTEM OPERATION CHECK
.
DTC 3 - BATTERY
1. Check that battery voltage is at least 8 volts. If not, check battery and/or charging system. Turn ignition
on and check voltage at joint connector terminals A or E (X-33).
2. If voltage is over 8 volts, replace SAS unit. See SAS UNIT
under REMOVAL & INSTALLATION. If
voltage is not over 8 volts, replace wiring harness from battery to fuse box. Perform SYSTEM
OPERATION CHECK .
DTC 6 - DRIVER-SIDE AIR BAG MODULE
1. Disable air ba
g system. See procedures under DISABLING & ACTIVATING AIR BAG SYSTEM. NOTE: When air bag warning light remains on, it can indicate a DTC 0 caused by no
continuity between terminal No. V and terminal No. Y of SAS unit This can be
due to a damaged SAS unit, an open or short circuit in wiring harness or poor
connections.
NOTE: For connector terminal identification, see WIRING DIAGRAM
.
NOTE: When voltage supplied to SAS unit is less than 1 volt due to weak battery, open
or short in wiring harness, poor connection of connector or damaged SAS unit,
DTC 3 will set
NOTE: For connector terminal identification, see WIRING DIAGRAM
.
NOTE: When resistance Is detected between terminals M-O of SAS unit is NOT 2 ohms,
DTC 6 will set.
NOTE: For connector terminal identification, see WIRING DIAGRAM
.
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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
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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.
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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.
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Fig. 9: Locating Hydraulic Unit Valve Relay Connector Terminals
Courtesy of MAZDA MOTORS CORP.
ABS WARNING LIGHT
Operational Test
1. Start engine and observe ABS warning light. Light should illuminate for a few seconds. If light does not
illuminate as described, turn ignition off. Disconnect ABS control module connector. Using a jumper
wire, connect terminal AD of ABS control module connector to ground. See Fig. 3
. Turn ignition on.
2. If ABS warning light illuminates, check ABS control module. See ABS CONTROL MODULE. If light
does not illuminate, remove instrument cluster. Remove and check ABS warning light bulb. Replace bulb
as necessary. If bulb is okay, check METER fuse and wiring harness. Repair or replace as necessary. If
METER fuse and wiring harness are okay, go to next step.
3. Using ohmmeter, connect positive lead to terminal 2K (Black/Yellow wire) of instrument cluster and
negative lead to terminal 1K (Blue/Yellow wire) of instrument cluster. See Fig. 10
. If continuity is not
present, replace instrument cluster. If continuity is present, repair wiring harness between instrument
cluster and ABS control module.
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Fig. 10: Identifying Instrument Cluster Connector Terminals
Courtesy of MAZDA MOTORS CORP.
STOPLIGHT SWITCH
Disconnect stoplight switch connector. Using ohmmeter, check continuity between stoplight switch terminals.
With brake pedal depressed, continuity should exist. With brake pedal released, continuity should not exist. If
continuity is not as specified, replace stoplight switch.
MOTOR RELAY
1. Turn ignition off. Disconnect ABS Control Module (ABS CM) connector. See COMPONENT
LOCATIONS . Connect Adapter Harness (49-F066-002) to ABS CM connector. Turn ignition on. Using
voltmeter, measure voltage between terminals "X" and AB of ABS CM connector. See Fig. 3
. Voltage
should be zero volts. Apply 12 volts to terminal "B" an d ground terminal "G" of ABS CM connector.
Using voltmeter, measure voltage between terminals "X" and AB of ABS CM connector. Voltage should
be 12 volts. If voltage is not as specified, check wiring harness. If wiring harness is okay, go to next step.
2. Remove motor relay from hydraulic unit. See Fig. 14
. Using ohmmeter, check continuity between
terminals "B" and "C" of motor relay. See Fig. 11
. Continuity should exist. Apply 12 volts to terminal
"C" and ground terminal "B". Using ohmmeter, check continuity between terminals "A" and "D" of motor
rela
y. Continuity should exist. If continuity is not as specified, replace motor relay.
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