1997 MAZDA MX-5 check engine

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.

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
Microsoft
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Fig. 15: Adjusting Master Cylinder Push Rod
Courtesy of MAZDA MOTORS CORP.
BRAKE PEDAL HEIGHT & STOPLIGHT SWITCH
1. Released pedal height is measured from carpet surface, on vertical portion of firewall, to pedal pad center.
Disconnect stoplight switch electrical connector. Loosen lock nut on stoplight switch. Rotate switch away
from pedal. Loosen push rod lock nut. Rotate push rod until correct pedal height is as specified. See
BRAKE PEDAL HEIGHT SPECIFICATIONS
table.
2. Adjust pedal free play. See BRAKE PEDAL FREE PLAY
under ADJUSTMENTS. Tighten push rod
lock nut. Tighten push rod lock nut to 18-25 ft. lbs. (24-34 N.m).
3. Rotate stoplight switch until it contacts pedal, then rotate an additional 1/2 turn. Tighten stoplight switch
lock nut to 10-13 ft. lbs. (14-18 N.m). Reconnect stoplight switch electrical connector.
4. Applied pedal height is measured from angled portion of firewall (without carpet) to pedal pad center.
Start engine. Depress brake pedal with a pressure of 132 lbs. (60 kg).
5. Measure applied pedal height. See BRAKE PEDAL HEIGHT SPECIFICATIONS
table. If distance is
not as specified, check for air in system or worn pads. Repair as necessary.
BRAKE PEDAL HEIGHT SPECIFICATIONS
BRAKE PEDAL FREE PLAY
ApplicationIn. (mm)
Pedal Released6.8-7.1 (171-181)
Pedal Applied (1) 3.7 (95)
(1)Minimum height.

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
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With engine off, depress pedal a few times to eliminate vacuum. Depress brake pedal by hand and check pedal
free play. See BRAKE PEDAL FREE PLAY SPECIFICATIONS
table. Adjust play by loosening push rod
lock nut. Turn push rod until correct free play is obtained. Tighten push rod lock nut to 18-25 ft. lbs. (24-34
N.m).
BRAKE PEDAL FREE PLAY SPECIFICATIONS
PARKING/EMERGENCY BRAKE
1. Depress brake pedal several times. Pull parking brake lever with a force of 44 lbs. (20 kg). If stroke is 7-9
notches, parking brake is properly adjusted. If stroke is not 7-9 notches, raise and support rear of vehicle.
Release parking brake lever.
2. Rotate cable adjusting nut at lever end of cable, located under console cover, until stroke is within
specification. Ensure rear brakes do not drag. Ensure parking brake warning light illuminates when brake
lever is pulled one notch.
TORQUE SPECIFICATIONS
TORQUE SPECIFICATIONS
WIRING DIAGRAMS
ApplicationIn. (mm)
Miata.16-.28 (4-7)
ApplicationFt. Lbs. (N.m)
Brake Caliper Mounting Bolts37-50 (50-68)
Brakeline Nuts10-16 (14-22)
Hydraulic Unit Brakeline Union Bolts18-26 (24-35)
Hydraulic Unit Mounting Bolts/Nuts14-18 (19-24)
I-Arm-To-Rear Steering Knuckle Bolt (RX7)44-54 (59-73)
Lower Control Arm-To-Rear Steering Knuckle Nut47-54 (64-73)
Push Rod Lock Nut18-25 (24-34)
Stoplight Switch Lock Nut10-13 (14-18)
Wheel Bearing Lock Nut
Front123-159 (167-216)
Rear159-217 (216-294)
Wheel Lug Nuts66-86 (89-117)
Wheel Speed Sensor Mounting Bolt12-16 (16-22)
INCH Lbs. (N.m)
ABS Control Unit Mounting Bolts/Nuts61-87 (6.9-9.8)

1997 Mazda MX-5 Miata
ANTI-LOCK BRAKE SYSTEM 1997 BRAKES Mazda - Anti-Lock
Microsoft
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Fig. 1: Locating Solenoid Valves
Courtesy of MAZDA MOTORS CORP.
SELF-DIAGNOSTIC SYSTEM
SYSTEM DIAGNOSIS
TCM monitors transmission operation and contains a self-diagnostic system which stores a Diagnostic Trouble
Code (DTC) if an electronic control system failure or component malfunction exists. If a problem exists in any
of the solenoids or speed sensors and DTC is set, TCM will deliver a signal to blink the HOLD indicator light
on instrument panel to warn the driver. DTC may be set if a failure exists and can be retrieved for transmission
diagnosis.
RETRIEVING TROUBLE CODES
NOTE: Before testing transmission, ensure fluid level is correct. Ensure engine starts
with shift lever in Park and Neutral to ensure proper adjustment of transmission
range switch. Transmission Control Module (TCM) must first be checked for
stored codes. See RETRIEVING TROUBLE CODES
.
NOTE: Before retrieving DTC, ensure proper battery voltage exists for self-diagnostic
system operation. If any DTC are present other than those listed below, see

1997 Mazda MX-5 Miata
1997 AUTOMATIC TRANSMISSIONS NC4A-EL Electronic Controls
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Using Scan Tool
Ensure ignition is in OFF position. Connect scan tool to Data Link Connector (DLC) located under left side of
instrument panel, near center console. Turn ignition switch to ON position. Check for stored DTC. See
DIAGNOSTIC TROUBLE CODE IDENTIFICATION
table. For trouble shooting of codes, see
DIAGNOSTIC TESTS
. appropriate SELF-DIAGNOSTIC SYSTEM article in ENGINE PERFORMANCE.

1997 Mazda MX-5 Miata
1997 AUTOMATIC TRANSMISSIONS NC4A-EL Electronic Controls
Microsoft
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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

1997 Mazda MX-5 Miata
1997 AUTOMATIC TRANSMISSIONS NC4A-EL Electronic Controls
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2. Measure voltage between terminal No. 1G (Green wire) and No. 2P (Black/Light Blue wire) on TCM
connector. Voltage should be about 3.3 volts at 77°F (25°C). If voltage is within specifications, go to step
6 . If voltage is not within specifications, go to next step.
3. Turn ignition off. Disconnect TCM harness connector. Measure resistance between terminals No. 1G and
No. 2P. See TFT SENSOR SPECIFICATIONS
table. If resistance is within specification, go to step 6 .
If resistance is not within specification, go to next step.
4. Inspect TFT sensor. Disconnect TFT sensor harness connector. Measure resistance between connector
terminals. See TFT SENSOR SPECIFICATIONS
table. If resistance is within specification, go to step
6 . If resistance is not within specification, replace TFT sensor.
5. Check continuity of circuits between TFT sensor and TCM. See appropriate wiring diagram in WIRING
DIAGRAMS . Repair as needed. If circuit is okay, go to next step.
6. Reconnect all harness connectors. Road test vehicle. Retrieve DTC. If code P0710 or P0711 is still
present, replace TCM. If code is no longer present, system is okay.
TFT SENSOR SPECIFICATIONS
DTC P0715: INPUT/TURBINE SPEED SENSOR
Condition
Input/Turbine speed sensor signal is not input to TCM when vehicle is moving. Possible causes for condition
are:
Input/Turbine speed sensor malfunction.
Damaged wiring or connectors between turbine speed sensor and TCM.
TCM malfunction.
Diagnosis & Repair Procedure
1. Turn ignition on. Using voltmeter, backprobe TCM harness connector. DO NOT disconnect connector.
Measure AC voltage between terminals No. 2J (positive) and No. 2L (negative). Voltage should be 0-.1
volts when idling and zero with engine stopped. If voltage is within specification, go to step 5 . If voltage
is not within specification, go to next step.
2. Turn ignition off. Disconnect TCM harness connector. Check for continuity between terminals No. 2J
(Yellow/Green wire) and No. 2L (Yellow/Blue wire). If continuity is present, go to step 5 . If continuity
is not present, go to next step.
3. Inspect sensor. See INPUT/TURBINE SPEED SENSOR
under COMPONENT TESTING. Repair as
needed. If sensor is okay, go to next step.
4. Check continuity of circuits between input/turbine speed sensor and TCM. See appropriate wiring
dia
gram in WIRING DIAGRAMS . Repair as needed. If circuits are okay, go to next step.
Fluid Temperaturek/ohms
68°F (20°C)2.5
140°F (60°C).6
176°F (80°C).35

1997 Mazda MX-5 Miata
1997 AUTOMATIC TRANSMISSIONS NC4A-EL Electronic Controls
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1. Inspect ATF level and condition. Correct as needed. If fluid level and condition is okay, check line
pressure. See LINE PRESSURE TEST under TESTING in MAZDA NC4A-EL OVERHAUL article.
Follow repair recommendations if line pressure is not within specifications. If line pressure is okay, go to
next step.
2. Inspect lock-up solenoid. See SOLENOID VALVES
under COMPONENT TESTING. Repair as
needed. If solenoid valve is okay, go to next step.
3. Inspect lock-up control valve in valve body. If valve is okay, go to next step.
4. Using an EC-AT tester connected to TCM, ensure that engine speed and turbine speed during TCC lock-
up in 4th gear are the same. If speeds are different, replace torque converter. If speeds are the same, go to
next step.
5. Clear DTC. See CLEARING CODES
. Retrieve DTC. If DTC P0740 is still present, replace TCM. If
code is no longer present and symptom still exists, problem may be caused by intermittent TCC slippage.
Further investigation may be required. See MAZDA NC4A-EL OVERHAUL article.
DTC P0750: 1-2 SHIFT SOLENOID MALFUNCTION
Possible Causes:
Short or open circuit between TCM and solenoid.
TCM malfunction.
Shift solenoid malfunction.
Diagnosis & Repair Procedure
1. Ensure all connections are clean and tight. Repair as needed. Turn ignition on. Access TCM connectors.
Using voltmeter, backprobe harness connectors. DO NOT disconnect connectors. Go to next step.
2. Measure voltage between ground and terminal No. 2E (Blue/Yellow wire) on TCM connector. During
test drive, voltage should be less than one volt when solenoid is off and battery voltage when solenoid is
on. See SOLENOID OPERATION
table under TCM OUTPUT DEVICES. If voltage is within
specification, go to step 5 . If voltage is not within specification, go to next step.
3. Turn ignition off. Disconnect TCM harness connector. Measure resistance between ground and terminal
No. 2E. If resistance is 13-27 ohms at 68°F (20°C), go to step 5 . If resistance is not 13-27 ohms at 68°F
(20°C), go to next step.
4. Inspect 1-2 shift solenoid and related circuits. See SOLENOID VALVES
under COMPONENT
TESTING. Repair as needed. If solenoid valve and related circuits are okay, go to next step.
5. Clear DTC and road test vehicle. Retrieve DTC. If DTC P0750 is still present, replace TCM. If code is no
longer present, system is okay.
DTC P0755: 2-3 SHIFT SOLENOID MALFUNCTION
Possible Causes:
Short or open circuit between TCM and solenoid.
TCM malfunction.

1997 Mazda MX-5 Miata
1997 AUTOMATIC TRANSMISSIONS NC4A-EL Electronic Controls
Microsoft
Sunday, July 05, 2009 1:35:04 PMPage 16 © 2005 Mitchell Repair Information Company, LLC.