Fig. 9: Removing/Installing SAS Unit
Courtesy of MAZDA MOTORS CORP.
Installation
To install, reverse removal procedure. Position SAS unit and bracket with arrow toward front of vehicle.
Tighten fasteners to specification. See TORQUE SPECIFICATIONS
. After SAS unit is installed, activate air
bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM
. Check AIR BAG warning light to
ensure system is functioning properly. See SYSTEM OPERATION CHECK
.
AIR BAG SYSTEM DEPLOYMENT AUTHORIZATION NOTE
New SAS units are not input with a deployment approval signal to prevent accidental deployment during
installation and will not operate properly until the signal is input.
1. Install new SAS unit and verify air bag warning light continuously flashes approximately 6 seconds after
ignition is turned on. Turn ignition to LOCK position and then back to ON position while warning light is
flashing.
2. Air bag warning light should illuminate and then go out after approximately 6 seconds. If warning light
does not go out, repeat procedure.
1997 Mazda MX-5 Miata
AIR BAG RESTRAINT SYSTEM 1997 ACCESSORIES/SAFETY EQUIPMENT Mazda - Air Bag Restraint System
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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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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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5. Reconnect all harness connectors. Road test vehicle. Retrieve DTC. If code P0715 is still present, replace
PCM. If code is no longer present, system is okay.
DTC P0725: ENGINE SPEED INPUT CIRCUIT MALFUNCTION
Condition
Engine speed input signal is not input to TCM. Possible causes are:
Crankshaft position sensor malfunction.
Damaged wiring or connectors between ECM and TCM.
ECM malfunction.
TCM malfunction.
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.
2. Measure voltage between ground and terminal No. 1N (White wire) on TCM harness connector. Voltage
should be zero or 4.5-5.5 volts with engine stopped or 2-3 volts with engine idling. If voltage is within
specifications, go to step 7 . If voltage is not within specifications, go to next step.
3. Ignition off. Measure continuity between terminal No. 1N (White wire) on TCM harness connector and
terminal No. 4F (White wire) on ECM harness connector. If continuity is not present, repair wiring then
go to step 7 .
4. Using voltmeter, backprobe ECM harness connector. Measure voltage between ground and terminal No.
4H (Yellow/White wire). Voltage should be less than one volt with engine stopped or greater than one
volt with engine idling. If voltage is within specifications, go to step 7 . If voltage is not within
specifications, go to next step.
5. Inspect crankshaft position sensor. See appropriate SYSTEM & COMPONENT TESTS article in
ENGINE PERFORMANCE. Replace as needed. If sensor is okay, go to next step.
6. Turn ignition off. Using ohmmeter, backprobe TCM harness connector. DO NOT disconnect connector.
Measure resistance between terminals 1N (White wire) and 2P (Black/Light Green wire). If resistance is
7.2-8.0 ohms, go to next step. If resistance is not 7.2-8.0 ohms, replace TCM.
7. Reconnect all harness connectors. Road test vehicle. Retrieve DTC. If code P0725 is still present, replace
TCM. If code is no longer present, problem is intermittent.
DTC P0731: INCORRECT 1ST GEAR RATIO NOTE: If DTC P0335 is also present, repair it first and then proceed with this test. Go to
appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE and
perform test.
NOTE: If any following DTC is also present, repair it first and then proceed with this
test: DTC P0750
, P0755 , P0760 .
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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. 2G (Orange 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. 2G. 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 2-3 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 trouble codes and road test vehicle. Retrieve DTC. If DTC P0755 is still present, replace TCM. If
code is no longer present, system is okay.
DTC P0760: 3-4 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. 2I (Blue 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 3-4 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 codes and road test vehicle. Retrieve DTC. If DTC P0760 is still present, replace TCM. If code is
no longer present, problem is intermittent. Further investigation may be necessary.
DTC P1720: VEHICLE SPEED SENSOR SIGNAL MISSING
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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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12 - 30 Amp (Green) Power Windows
13 - Empty
14 - Empty 15 - 15 Amp (Blue) Gauges, Warning Lights, Turn-Signal Lights, Cruise Control
16 - 15 Amp (Blue) Cooling Fan
17 - 30 Amp (Pink) Heater
18 - Empty
19 - Empty
20 - 10 Amp Defog (Some Models)
21 - 10 Amp Antenna (Some Models)
22 - Empty
1997 Mazda MX-5 Miata
MAINTENANCE INFORMATION 1997 MAINTENANCE Mazda Maintenance Information
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STEERING COLUMN
1995-97 STEERING Mazda Motors Corp. - Steering Columns
DESCRIPTION & OPERATION
Steering columns are designed to be collapsible upon impact. The steering column consists of solid steering
shaft with a lower joint assembly. Some models are equipped with tilt steering. Turn signal, headlight, ignition
and windshield washer/wiper switches are mounted on column. Switches can be serviced by removing steering
wheel and column covers. All models are equipped with air bag restraint system consisting of an driver air bag
module, passenger air bag module (except 1995 MPV and 1995 Protege) and clockspring connector assembly
located in the steering column.
SYSTEM OPERATION CHECK
1. Turn ignition switch to ON or START position. AIR BAG warning light in instrument cluster should
illuminate for about 4-8 seconds, and then turn off. This indicates air bag system is functioning properly.
2. If any of the following conditions exists, air bag system is malfunctioning and requires servicing.
AIR BAG warning light does not illuminate as specified.
AIR BAG warning light remains illuminated for more than 8 seconds.
AIR BAG warning light illuminates while driving.
3. If air bag system components are replaced for any reason, air bag system must be checked for proper
function after repair. Repeat step 1). If AIR BAG warning light does not illuminate as specified, air bag
system is malfunctioning and servicing is required. See AIR BAG RESTRAINT SYSTEM article.
SERVICE PRECAUTIONS
Observe the following precautions when servicing air bag system.
Disable air bag system before servicing any air bag system or steering column component. See AIR BAG
DISABLING & ACTIVATING .
After disabling air bag system, wait at least one minute before servicing. Air bag system voltage is
maintained for approximately one minute after system is disabled. Failure to wait one minute before
servicing system may cause accidental air bag deployment and possible personal injury.
Obtain radio code number from customer and deactivate radio anti-theft function (if equipped) before
disconnecting battery.
Because of the critical operation requirements of system, DO NOT service any air bag system
component. Repairs 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) air bag module, ensure trim cover is pointed away from your body. WARNING:To avoid injury from accidental air bag deployment, read and carefully
follow all WARNINGS and SERVICE PRECAUTIONS
.
1997 Mazda MX-5 Miata
STEERING COLUMN 1995-97 STEERING Mazda Motors Corp. - Steering Columns
1997 Mazda MX-5 Miata
STEERING COLUMN 1995-97 STEERING Mazda Motors Corp. - Steering Columns
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