transmission fluid MAZDA MIATA 1997 Factory Repair Manual

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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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

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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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1. Ensure all connections are clean and tight. Repair as needed. Turn ignition on. Using voltmeter,
backprobe TCM connector (as applicable). Measure voltage between ground and specified terminal. See
DTC P0705 VOLTAGE TEST
table. If all voltages are within specification, go to step 5 . If any voltage
is not within specification, go to next step.
DTC P0705 VOLTAGE TEST
2. Check continuity of circuits between transmission range switch and TCM. See appropriate wiring
diagram in WIRING DIAGRAMS
. Repair as needed. If all circuits are okay, go to next step.
3. Disconnect negative battery cable. Disconnect transmission range switch harness connector. Inspect
continuity of transmission range switch internal circuits. See TRANSMISSION RANGE SWITCH

under COMPONENT TESTING. Replace as needed. If switch is okay, go to next step.
4. Reconnect negative battery cable. Turn ignition on. Measure voltage at terminal "I" (Black/Blue wire) on
transmission range switch harness connector. If battery voltage does not exist, repair Black/Blue wire
between switch and ignition switch. If battery voltage exists, go to next step.
5. Road test vehicle. Retrieve DTC. If code P0705 is still present, replace TCM. If code is no longer present,
system is okay.
DTC P0710: TRANSMISSION FLUID TEMPERATURE (TFT) SENSOR CIRCUIT MALFUNCTION
& DTC P0711: TRANSMISSION FLUID TEMPERATURE (TFT) SENSOR CIRCUIT
RANGE/PERFORMANCE
Condition
Voltage input to TCM is less than .1 volt or greater than 5.0 volts. Possible causes for condition are:
Transmission fluid temperature sensor malfunction.
Damaged wiring or connectors between transmission fluid temperature sensor and TCM.
TCM 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.
TCM Terminal
No.Measured
Voltage
Range Switch Position
2B0"P" Or "N"
2B10-14"R", "D", "S" Or "L"
2D10-14"D"
2D0All Except "D"
2F10-14"S"
2F0All Except "S"
2H10-14"L"
2H0All Except "L"

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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

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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.

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between connector terminals and ground. Resistance should be 13-25 ohms. Replace solenoids as necessary.
Ensure transmission case is grounded.
VEHICLE SPEED SENSOR (VSS)
Disconnect negative battery cable. Remove combination meter. Disconnect harness connectors and speedometer
cable. Connect analog voltmeter leads to meter terminals "A" and "B". See Fig. 8
. Using appropriate
screwdriver, rotate speedometer cable shaft. If voltmeter needle does not fluctuate, replace sensor.
Fig. 8: Testing Vehicle Speed Sensor

Courtesy of MAZDA MOTORS CORP.
TRANSMISSION FLUID TEMPERATURE (TFT) SENSOR
Disconnect TFT sensor harness connector. Sensor is threaded into cooler line banjo mounting on side of
transmission case. Measure resistance between connector terminals. See TFT SENSOR SPECIFICATIONS

table.
TFT SENSOR SPECIFICATIONS NOTE: Vehicle speed sensor signal is input to TCM from combination meter driven by
speedometer cable.
Fluid Temperaturek/ohms
68°F (20°C)2.5
140°F (60°C).6

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1. Using Clutch Disconnect Tool (T88T-70522-A), disconnect hydraulic line at transmission. See Fig. 2 .
Clean reservoir cap area. Fill reservoir with DOT 3 brake fluid. Maintain fluid level in reservoir during
bleeding procedure.
2. Using small screwdriver, press and hold internal mechanism of male coupler to open valve. While
holding valve open, have an assistant slowly press and hold clutch pedal to floor.
3. Remove screwdriver to allow valve to close. Release clutch pedal. Refill reservoir.
4. Repeat steps 2) and 3). Install reservoir cap. Reconnect hydraulic line. Tug hydraulic line lightly to verify
secure connection.
5. As rapidly as possible, operate clutch pedal for full 5-10 strokes. Wait 3 minutes. Repeat this step at least
3 more times.
6. Loosen bleed screw, located next to release cylinder connection. Have an assistant press and hold clutch
pedal. Tighten bleed screw. Release pedal. Refill reservoir. Check clutch operation.
Fig. 2: Removing Hydraulic Line (B2300, B2500, B3000 & B4000)

Courtesy of MAZDA MOTORS CORP.
Miata
1. Remove bleeder screw cap located at clutch release cylinder. Install vinyl hose onto bleeder screw.

1997 Mazda MX-5 Miata
CLUTCH 1997-98 CLUTCHES Mazda - RWD
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Submerge other end of hose in container of brake fluid.
2. Fill reservoir with DOT 3 brake fluid. Have an assistant press and release clutch pedal several times, then
hold pedal down. With pedal pressed, loosen bleeder screw to let air and fluid escape.
3. Repeat step 2) until no more air bubbles emerge from hose. Tighten bleeder screw. Fill reservoir. Operate
clutch while inspecting for leaks. Check clutch and brake operation.
REMOVAL & INSTALLATION
CLUTCH ASSEMBLY
Removal (B2300, B2500, B3000 & B4000)
1. Disconnect negative battery cable. Shift transmission into Neutral. Remove gearshift lever. Raise and
support vehicle. Mark drive shaft flanges for installation reference. Remove drive shaft. Using Clutch
Disconnect Tool (T88T-70522-A), disconnect hydraulic line at transmission. See Fig. 2
. Plug hydraulic
line to prevent contamination. Disconnect wiring at transmission.
2. Remove starter. Remove exhaust components as necessary for clearance. On 4WD models, remove skid
plate and transfer case. On all models, secure transmission jack under transmission. Remove transmission
mount-to-crossmember nuts and bolts.
3. Remove nuts securing crossmember to frame side rails, and remove crossmember. Lower transmission
enough to gain access to transmission-to-engine block bolts. Remove transmission-to-engine block bolts.
Remove transmission.
4. If clutch parts are going to be reused, mark clutch cover and flywheel for reassembly reference. Loosen
pressure plate bolts evenly in crisscross pattern until springs are not under tension. Remove clutch cover
and clutch disc.
Inspection (B2300, B2500, B3000 & B4000)
1. Inspect disc for loose rivets, worn or defective springs, excessive wear, or oil contamination. Inspect
flywheel and clutch cover for burns, scoring, or grooves.
2. Measure flywheel and clutch cover runout. Resurface or replace flywheel and clutch cover if beyond
specification. See CLUTCH RUNOUT (MAXIMUM)
table.
3. Measure clutch disc runout. Replace disc if it is not to specification. See CLUTCH RUNOUT
(MAXIMUM) table. Inspect disc hub and input shaft splines for excessive wear. Hub must slide
smoothly on input shaft splines.
4. Inspect pilot bearing for wear. Apply inward pressure while rotating pilot bearing. If bearing sticks or has
excessive resistance, replace bearing. Check for tight fit in crankshaft. Replace as necessary. Inspect
release bearing for smooth operation, wear, damage, or looseness. Replace bearing as necessary.
CLUTCH RUNOUT (MAXIMUM)
ApplicationIn. (mm)
Disc0.028 (0.7)
Flywheel0.008 (0.20)

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CLUTCH 1997-98 CLUTCHES Mazda - RWD
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MOTORS
MOTORS
SENDING UNITS & SENSORS
SENDING UNITS & SENSORS
Key Interlock UnitBehind left side of dash. See Fig. 2 .
SAS UnitBehind center of dash. See Fig. 2 .
Transmission Control Module (TCM)Under left side of dash, near fuse block. See Fig. 2 .
ComponentComponent Location
Blower MotorUnder right side of dash. See Fig. 2 .
Condenser Fan MotorIn front of engine compartment.
Cooling Fan MotorIn front of engine compartment.
Cruise Control ActuatorOn left side of engine compartment.
Fuel PumpIn fuel tank.
Power Antenna MotorIn right front of trunk.
Retractable Headlamp ActuatorsBehind respective headlamp.
Shift Lock ActuatorUnder center console, on base of gear selector.
Windshield Washer MotorOn bottom of washer fluid reservoir.
Windshield Wiper MotorOn right side of firewall.
ComponentComponent Location
ABS Wheel Speed Sensor (Left Front)On back of left front wheel spindle assembly. See Fig. 1 .
ABS Wheel Speed Sensor (Left Rear)On back of left rear wheel hub assembly. See Fig. 3 .
ABS Wheel Speed Sensor (Right Front)On back of right front wheel spindle assembly. See Fig. 1 .
ABS Wheel Speed Sensor (Right Rear)On back of right rear wheel hub assembly. See Fig. 3 .
Brake Fluid Level SensorIn brake fluid reservoir. See Fig. 1 .
Camshaft Position SensorIn center rear of engine compartment. See Fig. 1 .
Crankshaft Position SensorOn front of engine.
EGR Boost SensorOn right side of engine compartment.
EGR Valve Position SensorOn right side center, rear of engine compartment.
EGR Valve Position SensorOn right side center, rear of engine compartment. See Fig. 1 .
Engine Coolant Temperature SensorOn rear of engine. See Fig. 1 .
Fuel Gauge Sender UnitIn fuel tank.
Heated Oxygen Sensor (Front)In rear of engine compartment. See Fig. 1 .
Heated Oxygen Sensor (Rear)On underside of vehicle, on exhaust pipe.
Input/Turbine Speed SensorOn left side of transmission.
Mass Air Flow SensorOn top of air filter housing. See Fig. 1 .
Throttle Position (TP) SensorOn side of throttle body. See Fig. 1 .
Transmission Fluid Temperature SensorOn left side of transmission.

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