DIAGNOSIS
SELF-DIAGNOSTIC SYSTEM
SAS unit will only display one code at a time. SAS unit will always display highest priority code first. After
repairing system, perform SYSTEM OPERATION CHECK
. If AIR BAG warning light is still flashing
during SYSTEM OPERATION CHECK, record code displayed. Repair system as necessary.
Retrieving & Clearing Codes
If codes are stored, AIR BAG warning light will flash or remain on when ignition is turned on. Codes are
automatically cleared when fault is corrected.
AIR BAG Warning Light Flashes
AIR BAG warning light indicates fault codes by flashing. Count the number of flashes between pauses to
determine code. See AIR BAG CODES
table. Codes are prioritized. If 2 or more faults are present, SAS unit
will display highest priority code first. After identifying code, go to appropriate code test.
AIR BAG Warning Light Remains On
Illumination of AIR BAG warning light continuously when ignition is turned on indicates a Code 0 (zero). See
AIR BAG CODES
table.
AIR BAG Warning Light Does Not Come On
Check for blown fuses, burned-out bulb, disconnected SAS unit, or open circuit between warning light and SAS
unit.
AIR BAG CODES
WARNING LIGHT DOES NOT COME ON WARNING:Follow air bag service precautions to prevent accidental air bag
deployment and personal injury. See SERVICE PRECAUTIONS
.
NOTE: If AIR BAG warning light does not come on and buzzer sounds when ignition is
turned on, check and repair warning light circuit first.
CodePossible Cause
0 (1) SAS unit
3Power Source Circuit
6Driver-Side Air Bag Module Circuit
7Passenger-Side Air Bag Module Circuit
(1)AIR BAG warning light remains on, indicating a Code 0.
1997 Mazda MX-5 Miata
AIR BAG RESTRAINT SYSTEM 1997 ACCESSORIES/SAFETY EQUIPMENT Mazda - Air Bag Restraint System
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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
.
1997 Mazda MX-5 Miata
AIR BAG RESTRAINT SYSTEM 1997 ACCESSORIES/SAFETY EQUIPMENT Mazda - Air Bag Restraint System
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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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4. Check wiring harness for open or short to ground between hydraulic unit and ABS control module. See
WIRING DIAGRAMS
. Repair as necessary. If wiring harness is okay, go to next step.
5. Clear DTCs. See CLEARING CODES
under DIAGNOSIS & TESTING. Recheck for DTCs. If DTC
22, 23, 24, 25, 26 or 27 is displayed, replace ABS control module. If DTC 22, 23, 24, 25, 26 or 27 is not
displayed, a temporary poor contact in wiring may have occurred and ABS is now functioning properly.
DTC 51: VALVE RELAY OR WIRING HARNESS
1. Check BTN fuse. Replace as necessary. If BTN or ABS fuse is okay, go to next step.
2. Check valve relay. See VALVE RELAY
under COMPONENT TESTING. Replace as necessary. If
valve relay is okay, check wiring harness for open or short to ground between valve relay and ABS
control module. See WIRING DIAGRAMS
. Repair as necessary. If wiring harness is okay, go to next
step.
3. Clear DTCs. See CLEARING CODES
under DIAGNOSIS & TESTING. Recheck for DTCs. If DTC 51
is displayed, replace ABS control module. If DTC 51 is not displayed, a temporary poor contact in wiring
may have occurred and ABS is now functioning properly.
DTC 53: PUMP MOTOR, MOTOR RELAY OR WIRING HARNESS
1. Turn ignition off and check if pump motor continues to operate. If pump motor continues operating after
ignition is off, replace motor relay. If pump motor does not continue to operate after ignition is off, go to
next step.
2. Check ABS fuse. Replace as necessary. If ABS fuse is okay, go to next step.
3. Check motor relay. See MOTOR RELAY
under COMPONENT TESTING. Replace as necessary. If
motor relay is okay, check wiring harness for open or short to ground between motor relay and ABS
control module. See WIRING DIAGRAMS
. Repair as necessary. If wiring harness is okay, go to next
step.
4. Check pump motor. See PUMP MOTOR
under COMPONENT TESTING. Replace as necessary. If
pump motor is okay, check wiring harness for open or short to ground between hydraulic unit and ABS
control module. Repair as necessary. If wiring harness is okay, go to next step.
5. Clear DTCs. See CLEARING CODES
under DIAGNOSIS & TESTING. Recheck for DTCs. If DTC 53
is displayed, replace ABS control module. If DTC 53 is not displayed, a temporary poor contact in wiring
may have occurred and ABS is now functioning properly.
DTC 61: ABS CONTROL MODULE
1. Check ABS control module connector for poor connection. See COMPONENT LOCATIONS
. Repair
as necessary. If connector is okay, go to next step.
2. Clear DTCs. See CLEARING CODES under DIAGNOSIS & TESTING. Recheck for DTCs. If DTC 61
is displayed, replace ABS control module. If DTC 61 is not displayed, a temporary poor contact in wiring
may have occurred and ABS is now functioning properly.
COMPONENT TESTING
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ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
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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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ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
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OPERATION
TCM
TCM receives information from various input devices and uses this information to control solenoids on
transmission valve body for transmission shifting and torque converter clutch engagement.
TCM automatically switches from NORMAL mode to POWER mode corresponding to driving condition in
"D" range. Upshifts and downshifts are performed at a higher speed in POWER mode than in NORMAL mode.
TCM contains a self-diagnostic system, which will store Diagnostic Trouble Codes (DTC) if a failure or
problem exists in electronic control system. DTC can be retrieved to determine problem area. See SELF-
DIAGNOSTIC SYSTEM . TCM is located under left side of instrument panel, above fuse block.
TCM INPUT DEVICES & SIGNALS
4th Gear Inhibit Signal
Signal is input to TCM when cruise control is on. Signal detects when difference between target speed and
actual speed exceeds specification.
HOLD Switch
HOLD switch delivers input to TCM to indicate gears preferred by operator. Switch is located on shift lever
handle. HOLD switch is canceled when ignition switch is turned off.
Input/Turbine Speed Sensor
Sensor is a magnetic pick-up type pulse generator that monitors input shaft speed. AC waveform is input to
TCM by output speed sensor. Sensor is located on front of transmission, back of converter housing.
Throttle Position (TP) Sensor
TP sensor delivers an input signal to TCM indicating throttle valve position (opening). TP sensor is located on
side of throttle body.
Transmission Range Switch
Transmission range switch delivers an input signal to TCM indicating shift lever position. Switch is located on
side of transmission.
Transmission Fluid Temperature (TFT) Sensor
TFT sensor is threaded into cooler line banjo mounting on side of transmission case. Sensor sends signal to
TCM indicating fluid temperature.
Vehicle Speed Sensor
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1997 AUTOMATIC TRANSMISSIONS NC4A-EL Electronic Controls
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CLEARING CODES
To clear DTC stored in TCM, use scan tool. See scan tool instruction manual. Road test vehicle.
COMPONENT LOCATION
COMPONENT LOCATION
COMPONENT CONNECTOR IDENTIFICATION
P0706 Transmission Range Sensor Range/Performance
P0710 (2) TFT Sensor Malfunction
P0711 (2) TFT Sensor Range/Performance
P0715 Input/Turbine Speed Sensor
P0725 Engine Speed Input Circuit Malfunction
P0731 Incorrect 1st Gear Ratio
P0732 Incorrect 2nd Gear Ratio
P0733 Incorrect 3rd Gear Ratio
P0734 Incorrect 4th Gear Ratio
P0740 TCC System Malfunction
P0750 1-2 Shift Solenoid
P0755 2-3 Shift Solenoid
P0760 3-4 Shift Solenoid
P1720 Vehicle Speed Sensor
P1743 Lock-Up Solenoid Valve
P1765 3-2 Timing Control Solenoid Valve
P1790 Throttle Position Sensor
P1795 Idle Switch
(1)Check listed component for probable cause. Check wiring and connection of specified component.
(2)Transmission Fluid Temperature.
DescriptionLocation
Engine Control ModuleBehind Passenger Seat
Input/Turbine Speed SensorMounted To 4th Gear Case
Shift SolenoidsSee Fig. 1
TCC Lock-Up SolenoidSee Fig. 1
Transmission Control UnitAbove Fuse Box
3-2 Control ValveSee Fig. 1
TFT SensorMounted In-Line To Cooler Line
Vehicle Speed SensorMounted In Speedometer
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1997 AUTOMATIC TRANSMISSIONS NC4A-EL Electronic Controls
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TCM TERMINAL VOLTAGE TESTS
Turn ignition switch to ON position. Access TCM. TCM is mounted under left corner of dash, above fuse box.
DO NOT disconnect harness connector. Using DVOM, measure voltage. See Fig. 4
for terminal identification.
See Fig. 10
and Fig. 11 . After verifying that appropriate condition has been met, check voltage. If voltage is
not within specification, inspect component or appropriate circuit. If voltage is within specification, replace
TCM.
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1997 AUTOMATIC TRANSMISSIONS NC4A-EL Electronic Controls
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