sensor MAZDA MX-5 1997 Factory Owner's Manual

Condition
Vehicle speed sensor signal is not input to TCM. Possible causes are:
Vehicle speed sensor malfunction.
Vehicle speedometer sensor malfunction.
Damaged circuits or connectors between sensors and TCM.
Diagnosis & Repair Procedure
1. Ensure all connections are clean and tight. Repair as needed. Turn ignition on. Using voltmeter,
backprobe TCM harness connector. DO NOT disconnect connector. Test drive vehicle.
2. Measure voltage between ground and terminal No. 1P (Green/Red wire) on TCM harness connector.
During test drive voltage should be about 4 volts. When parked, voltage should be less than 1.5 or 7-9
volts. If voltage is within specifications, go to step 5 . If voltage is not within specifications, go to next
step.
3. Turn ignition off. Disconnect negative battery cable. Remove instrument cluster. Disconnect TCM
harness connectors. Ensure continuity exists on Green/Red wire between terminal No. 1P on TCM
connector and terminal No. 2F on instrument cluster harness left connector. Repair as needed. If
continuity exists, go to next step.
4. With combination meter removed, measure voltage between terminals No. 2F and 2D on combination
meter connector using analog voltmeter. Raise and support vehicle. Rotate rear wheels. If voltage pulse is
present, go to next step. If voltage pulse is not present, inspect speedometer cable. Replace as needed. If
cable is okay, replace combination meter or circuit board (as applicable).
5. Clear codes and road test vehicle. Retrieve DTC. If DTC 1720 is still present, replace TCM. If code is no
longer present, problem may be caused by poor connection. Repair as needed.
DTC P1743: TORQUE CONVERTER CLUTCH (TCC) SOLENOID MALFUNCTION
Possible Causes:
Short or open circuit between TCM and solenoid.
TCM malfunction.
Lock-up 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. 2K (Yellow/Black wire). Battery voltage should be
present with solenoid on and zero volts with solenoid off. If voltage is within specifications, go to step 5 .
If voltage is not within specifications, go to next step.
3. Turn ignition off. Disconnect TCM harness connector. Measure resistance between ground and terminal
No. 2K. If resistance is 13-25 ohms at 68°F (20°C), go to step 5 . If resistance is not 13-25 ohms at 68°F
(20°C),
go to next step.

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4. Inspect lock-up 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 codes and road test vehicle. Retrieve DTC. If DTC P1743 is still present, replace TCM. If code is
no longer present, problem may be caused by poor connection. Repair as needed.
DTC P1765: 3-2 CONTROL SOLENOID VALVE MALFUNCTION
Possible Causes:
Short or open circuit between TCM and solenoid.
TCM malfunction.
3-2 control 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. Drive vehicle and measure voltage between ground and terminal No. 2M (Blue/Orange wire). Battery
voltage should be present with solenoid on during 3-2 or 4-3 downshift, and zero volts with solenoid off.
If voltage is within specifications, go to step 5 . If voltage is not within specifications, go to next step.
3. Turn ignition off. Disconnect TCM harness connector. Measure resistance between ground and terminal
No. 2M. 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 3-2 control clutch 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 codes and road test vehicle. Retrieve DTC. If DTC P1765 is still present, replace TCM. If code is
no longer present, problem may be caused by poor connection. Repair as needed.
DTC P1790: THROTTLE POSITION (TP) SENSOR MALFUNCTION
Condition
TP sensor voltage is less than one volt or more than 4.9 volts. Possible causes are:
Poor harness connection at TP sensor.
Circuit fault between TP sensor and ECM or TCM.
TP sensor malfunction.
ECM or TCM malfunction.
Diagnosis & Repair Procedure
NOTE: If DTC P0725 is also present, repair it first and then proceed with this test.

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1. Ensure all connections are clean and tight. Repair as needed. Ensure that TP sensor is adjusted correctly.
See appropriate ON-VEHICLE ADJUSTMENTS article in ENGINE PERFORMANCE. 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. 2T (Red/Black wire) on TCM harness connector. With
throttle closed, voltage should be .1-1.1 volts. With wide open throttle, voltage should be 3.1-4.4 volts. If
voltage is within specification, go to step 5 . If voltage is not within specification, go to next step.
3. Measure voltage between ground and terminal No. 2A (Light Green/White wire) on TCM harness
connector. With ignition on, voltage should be 4.5-5.5 volts. With ignition off, voltage should be zero
volts. If voltage is within specification, go to step 5 . If voltage is not within specification, go to next step.
4. Inspect circuits between TP sensor and TCM. See appropriate wiring diagram under WIRING
DIAGRAMS . Repair as needed. If circuits are okay between sensor and TCM, go to next step.
5. Clear codes, and road test vehicle. Retrieve DTC. If DTC P1790 is still present, replace TCM. If code is
no longer present, system is okay.
DTC P1795: IDLE SWITCH OPEN OR SHORT
Condition
Closed throttle position switch is ON and TP sensor position is closed. Possible causes are:
Damaged wiring or connectors between closed throttle position switch and TCM.
Closed throttle position switch malfunction.
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.
2. Measure voltage between ground and terminal No. 1O (Red wire) on TCM harness connector. With
throttle closed, battery voltage should be present. With wide open throttle, voltage should be zero volts. If
voltage is within specification, go to step 5 . If voltage is not within specification, go to next step.
3. Inspect circuits between closed throttle position switch and TCM. See appropriate wiring diagram under
WIRING DIAGRAMS
. Repair as needed. If circuits are okay between sensor and TCM, go to next
step.
4. Disconnect battery negative cable. Disconnect closed throttle position switch connector. Check for
continuity between closed throttle position switch terminals. If continuity exists, go to next step. If
continuity does not exist, replace or adjust throttle position sensor.
5. Clear codes, and road test vehicle. Retrieve DTC. If DTC P1795 is still present, replace TCM. If code is
no longer present, problem is intermittent. Further investigation is required.
COMPONENT TESTING
NOTE: For connector terminal identification, see COMPONENT CONNECTOR

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HOLD SWITCH
1. Turn ignition on. Ensure HOLD indicator illuminates with switch depressed. Ensure indicator light is not
illuminated when switch is released. If switch is not working as described, go to next step.
2. Access switch connector under center console. Disconnect connector. Check continuity between
terminals "A" and "B". See Fig. 6
. Continuity should exist when switch is depressed. When switch is
released, continuity should not exist. Replace as needed. If HOLD switch system does not function
correctly, inspect circuits between switch and TCM. See appropriate wiring diagram in WIRING
DIAGRAMS .
Fig. 6: Testing HOLD Switch

Courtesy of MAZDA MOTORS CORP.
INPUT/TURBINE SPEED SENSOR IDENTIFICATION
table under SELF-DIAGNOSTIC SYSTEM. For circuit or wire
color identification, see appropriate wiring diagram in WIRING DIAGRAMS
.

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Disconnect output speed sensor connector. See Fig. 3. Measure resistance between terminals. Resistance
should be 245 ohms. Replace as needed.
SOLENOID VALVES (EXCEPT TCC SOLENOID)
Disconnect negative battery cable. Disconnect transmission solenoid harness connector. See Fig. 3
. Note that
solenoids ground through transmission case. Check resistance between connector terminals and ground. See
Fig. 7
. Resistance should be 13-27 ohms. Replace solenoids as necessary. See SOLENOID VALVE
IDENTIFICATION table. Ensure transmission case is grounded.
Fig. 7: Identifying Solenoid Valve Terminals

Courtesy of MAZDA MOTORS CORP.
SOLENOID VALVE IDENTIFICATION
TCC SOLENOID
Disconnect ne
gative battery cable. Disconnect TCC solenoid harness connector. See Fig. 3 . Check resistance
Solenoid Valve(1) Terminal No.
1-2 Shift SolenoidC
2-3 Shift SolenoidD
3-4 Shift SolenoidA
3-2 ControlB
(1)See Fig. 7 for terminal identification.

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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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Fig. 11: TCM Pin Voltage Table (2 Of 2)
Courtesy of MAZDA MOTORS CORP.
ELECTRICAL SPECIFICATIONS
SOLENOID RESISTANCE SPECIFICATIONS
ComponentResistance Ohms
Solenoids
Shift Solenoids13-27
TCC Solenoid13-25
Sensor
TSS245

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1997-2001 DRIVE AXLES
Axle Shafts - MX-5 Miata
TROUBLE SHOOTING
Inspect CV joint boot on axle shaft for cracks, damage, leaking, grease, and looseness in boot band. Inspect axle
shaft for bending, cracks, and wear of joint splines. Repair or replace as necessary.
REMOVAL & INSTALLATION
AXLE SHAFTS
Removal
1. Raise vehicle and support with safety stands. Remove wheel and tire assembly. Remove axle shaft lock
nut. See Fig. 1
.
2. Remove brake caliper assembly. Remove lower control arm bolt at knuckle, and pull knuckle/hub
assembly outward. Using pry bar between differential housing and inner CV joint, remove inner CV joint
from differential. See Fig. 2
. Remove axle shaft from knuckle/hub assembly. NOTE: See DRIVE AXLE NOISE DIAGNOSIS article in GENERAL INFORMATION.
CAUTION: If vehicle is equipped with ABS, before performing following procedure,
remove ABS wheel speed sensor (axle side) and fix it to an appropriate
place where sensor will not be pulled by mistake while servicing vehicle.
NOTE: If axle shaft will not come out of rear hub support easily, install a discarded nut
onto axle shaft so that nut is flush with end of axle shaft. Tap nut with a copper
hammer to loosen axle shaft from wheel hub.

1997 Mazda MX-5 Miata
1997-2001 DRIVE AXLES Axle Shafts - MX-5 Miata

1997 Mazda MX-5 Miata
1997-2001 DRIVE AXLES Axle Shafts - MX-5 Miata
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MASTER CYLINDER
Removal & Installation
Disconnect fluid level sensor electrical connector at fluid reservoir. Disconnect and plug brake lines at master
cylinder to prevent entry of dirt and loss of fluid. Remove nuts attaching master cylinder to power brake unit.
Remove master cylinder from vehicle. To install master cylinder, reverse removal procedure. Bleed air from
system.
POWER BRAKE UNIT
Removal & Installation
Remove master cylinder from power brake unit. See MASTER CYLINDER . Disconnect vacuum line at
power brake unit. See Fig. 19 . From inside vehicle, remove cotter pin and clevis pin. Separate push rod from
brake pedal. Remove power brake unit-to-firewall nuts. Remove power brake unit. To install, reverse removal
procedure. Bleed air from system.
Fig. 19: Removing Power Brake Unit (Typical)

Courtesy of MAZDA MOTORS CORP.
OVERHAUL
in SUSPENSION.

1997 Mazda MX-5 Miata
BRAKE SYSTEM 1995-97 BRAKES Mazda - Disc & Drum
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axle shaft housing. Remove axle oil seal. See Fig. 5. With axle shaft removed, remove retaining ring.
Remove ABS sensor rotor.
4. To remove bearing collar, grind collar until a section about .02" (.50 mm) remains. Using chisel, cut
remaining bearing collar from axle shaft. Using Puller (49-S121-520A), remove axle bearing from axle
shaft. Remove dust shield and backing plate.
5. Using dial indicator and "V" blocks, check axle shaft for straightness. Maximum axle shaft runout
is .059" (1.50 mm). Also check axle shaft splines for wear and damage. Use a press to replace wheel studs
as necessary. DO NOT reuse wheel studs if removed.
Installation
To install, reverse removal procedure. Lubricate oil seal lip before replacement. Use Attachment (49-1011-748)
and a press to install axle bearing onto axle shaft. DO NOT lubricate bearing collar before replacement. Use
Attachment (49-1011-748) and a press to install NEW bearing collar. If press fit of collar requires less than 2.7
tons (2699 k
g) to install, replace axle shaft. Tighten nuts to specification. See TORQUE SPECIFICATIONS.

1997 Mazda MX-5 Miata
1997-98 DRIVE AXLES Differentials & Drive Axles - MPV & MX-5 Miata
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