Mazda MX-6 1998, Workshop Manual

Page: 559 / 1282

CONTROL SYSTEM [KL]
(2) Turn the ignition switch to ON.
(3) Select the “ PID/DATA MONITOR AND
RECORD” function on the NGS tester display
and press TRIGGER.
(4) Select “ IAT V” on the NGS tester display and
press START. The NGS tester measures and
shows the voltage.
Specification____________
Intake air temperature
condition
"IAT V” voltage (V)
20 ’ C {68 °F) Approx. 3.1
(5) If not as specified, check the related harness
and intake air temperature sensor resistance.
Inspection of Resistance
1. Remove the intake air temperature sensor.
2. Place the intake air temperature sensor in water
with a thermometer, and heat the water gradually.
3. Measure the resistance of the intake air
temperature sensor by using an ohmmeter.
Specification
Water temperature (°C {°F}) Resistance (k£2)
20 {68)
35.5— 39.2
6 0(140}
7.18— 7.92
4. If not as specified, replace the intake air
temperature sensor.
Tightening torque
10.8— 16.2 N m
{110— 166 kgf cm, 95.5— 144 in lbf}
HEATED O XYG EN SEN SO R INSPECTIO N [KL]
Heated Oxygen Sensor Inspection
1.
If
the
SS T
(104 Pin Breakout Box) are used,
check in the following order.
(1) Remove the PCM. (Refer to 01-4 0 B
POWERTRAIN CONTROL MODULE (PCM)
REMOVAL/INSTALLATION [KL].)
(2) Connect the SST (104 Pin Breakout Box) to
the PCM as shown.
W6U140WMS
(3) Tighten the connector bolt.
Tightening torque
7.9— 10.7 N-m
{80— 100 kgf-cm , 69.5— 95.4 in-lbf}
(4) Warm up the engine to normal operating
temperature.
(5) Measure the voltage at PCM terminal 35, 60,
61 and 87.
W 6 U 1 4 0 W 0 Q
Specification
Engine
condition
PCM terminal voltage (V)
60 87
3 5
61
Heated
oxygen
sensor
(Front
RH)
Heated
oxygen
sensor
(Front
LH)
Heated
oxygen
sensor
(Middle)
Heated
oxygen
sensor
(Rear)
I G - O N Below 1.0
A fte r w a r m u p 0.1— 0.9
E n g in e c o ld Below 0.5 Below 0.5 Below 0.5 Approx. 0
D e c e le r a tio n 0 - 0 . 5 0 - 0 . 5 0 - 0 . 5
—
A c c e le r a tio n 0 .5 - 1 .0 0 .5 - 1 .0 0.5— 1.0
—
(6) If not as specified, inspect the following.
• intake-air system
• Fuel system
• On-board diagnostic system
• Related harnesses
(7) If these systems are okay, replace the heated
oxygen sensor. (Refer to 01-15 EXHAUST
SYSTEM REMOVAL/INSTALLATION [KL].)
2. If the
SSTs
(NGS tester) are used, check in the
following order.
(1) Connect the
SSTs
(NGS tester) to the data
link connector.
INTAKE AIR TEMPERATURE
SENSOR
W 6 U 1 4 0 W M R
PCM
HARNESS
0 1 -4 0 B -2 4