2002 MAZDA 6 engine

CONTROL SYSTEM
F2–71
F2
IDLE SWITCH ADJUSTMENTA6E404041600202
Caution
•Adjusting the idle switch unnecessarily may adversely affect engine control. Therefore, adjust the
idle switch only when it is replaced.
1. Verify that the accelerator position sensor is normal.
2. Visually inspect all accelerator pedal components for looseness.
3. Loosen the locknut that secures the idle switch.
4. Verify that the power circuit voltage.
(1) Verify that the voltage between the PCM terminals 90 (power circuit) and 91(GND circuit) is 4.75—5.25 V.
Note
•Voltage at the PCM terminal 10 may deviate when the power circuit voltage is abnormal.
5. Depress the accelerator pedal by hand and
secure it when the voltage between the PCM
terminals 10 (accelerator position detection
signal) and 91 is within the range specified below.
Voltage range
0.9—1.1V (Target value: 1.0 V)
6. Turn the idle switch under the condition in Step 5.
Secure the idle switch when the continuity turns
from OFF to ON, and tighten the locknut.
7. Release the accelerator pedal. Depress the
accelerator pedal again and verify that the idle
switch continuity changes from OFF to ON when
the PCM terminal 10 voltage is within 0.9—1.1 V.
•If the continuity does not change, repeat Step
6.
End Of Sie
ACCELERATOR POSITION SENSOR
IDLE SWITCHPCM B
A
C
D
A
B31 10
90
88
91
A6E40702037
ACCELERATOR PEDAL
A6E40702039
IDLE SWITCH
LOCKNUTA
B
A6E40702040

CONTROL SYSTEM
F2–73
F2
ACCELERATOR POSITION SENSOR ADJUSTMENTA6E404041602202
Caution
•Adjusting the accelerator position sensor unnecessarily may adversely affect engine control.
Therefore, adjust accelerator position sensor only when it is replaced.
Note
•Accelerator position sensor adjustment is based on the output voltage with the accelerator pedal fully
released. Therefore, be sure to adjust according to the following procedure. (Begin adjustment with the
accelerator pedal fully released.)
1. Visually inspect all accelerator pedal components for looseness.
2. Install the accelerator position sensor.
3. Verify the power circuit voltage.
(1) Verify that the voltage between the PCM terminals 90 (power circuit) and 91 (GND circuit) is 4.75—5.25 V.
Note
•Voltage at the PCM terminal 10 may deviate when the power circuit voltage is abnormal.
4. Adjust the output voltage when the accelerator
pedal is fully released.
(1) Verify that the voltage between the PCM
terminals 10 (accelerator position detection
signal) and 91 is as shown below according to
the accelerator pedal conditions.
•If not as specified, move the accelerator
position sensor to adjust the installation
position of the accelerator position sensor
so that the PCM terminal 10 voltage is
within the specification.
Specification
5. Verify that the output voltage when the accelerator pedal is fully depressed.
(1) Depress the accelerator pedal fully and verify that the voltage at the PCM terminal 10 is within the
specification.
Specification3.4—3.8V (Target value: 3.6 V)
6. After completion of Steps 1. through 5, inspect the idle switch.
End Of SieAccelerator pedal
conditionOutput voltage (V)
Fully released 0.5—0.7 (Target value: 0.6)
Gradually depressed Increases linearly
ACCELERATOR POSITION SENSOR
PCM
B
A
C
D10
90
88
91
A6E40702041

F2–74
CONTROL SYSTEM
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTIONA6E404013210201
Note
•Perform the following test only when directed.
•Perform “MAF Correction” after replacing the MAF/IAT sensor. (See F2–35 MAF Correction.)
MAF Sensor Voltage Inspection
1. Turn the engine switch to ON.
2. Monitor the MAF PID using the WDS or equivalent.
•If not as specified, perform the “Circuit Open/Short Inspection”.
MAF PID
0.0—1.0 V
3. Start the engine and warm up the engine completely.
4. Monitor the MAF PID using the WDS or equivalent at idle.
•If not as specified, perform the “Circuit Open/Short Inspection”.
MAF PID
1.5—2.1 V
MAF Sensor CIrcuit Open/Short Inspection
1. Inspect for open/short circuit in the following
wiring harnesses.
•If there is open/short circuit, repair or replace
wiring harnesses.
Open circuit
•Power circuit
—MAF/IAT sensor terminal A and PCM control
relay terminal C
•Signal circuit
—MAF/IAT sensor terminal C and PCM terminal
9
•GND circuit
—MAF/IAT sensor terminal B and PCM terminal 14
Short circuit
•Power circuit
—MAF/IAT sensor terminal A and PCM control relay terminal C to GND
•Signal circuit
—MAF/IAT sensor terminal C and PCM terminal 9 to power circuit
—MAF/IAT sensor terminal C and PCM terminal 9 to GND
MAF/IAT SENSOR
HARNESS SIDE CONNECTOR
A
B
C
D E
A6E40702043

F2–76
CONTROL SYSTEM
ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATIONA6E404018840201
Warning•When the engine is hot, it can badly burn. Turn off the engine and wait until it is cool before
removing the ECT sensor.
1. Disconnect the negative battery cable.
2. Drain the engine coolant. (See Section E ENGINE COOLANT REPLACEMENT.)
3. Remove the common rail. (See F2–53 SUPPLY PUMP REMOVAL/INSTALLATION .)
4. Remove in the order indicated in the table.
5. Install in the reverse order of removal.
End Of Sie
ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTIONA6E404018840202
Note
• Perform the following test only when directed.
Resistance Inspection 1. Place the ECT sensor in water with a thermometer, and heat the water gradually.
2. Measure the resistance between the ECT sensor terminals using an ohmmeter.
• If not as specified, replace the ECT sensor.
Specification
Circuit Open/Short Inspection 1. Inspect for open/short circuit in the following
wiring harnesses.• If there is open/short circuit, repair or replace
wiring harness.
Open circuit • Signal circuit
— ECT sensor terminal A and PCM terminal 87
• GND circuit
— ECT sensor terminal B and PCM terminal 91
Short circuit • Signal circuit
— ECT sensor terminal A and PCM terminal 87 to power circuit
— ECT sensor terminal A and PCM terminal 87 to GND
End Of Sie
1ECT sensor
2Gasket149 D015 001
N·m {kgf·m, ft·lbf}
16—23
{1.6—2.4, 12—17}2R
A6E40702045
Water temperature (
°C { °F}) Resistance (kilohm)
20 {68} 2.21—2.69
80 {176} 0.29—0.34A
B
A6E40702046

F2–78
CONTROL SYSTEM
BOOST SENSOR INSPECTIONA6E404013214201
Note
•Perform the following test only when directed.
Visual Inspection
1. Inspect the boost sensor for damage and cracks.
•If not as specified, replace the boost sensor.
2. Inspect vacuum hose for improper routing, kinks or leakage.
•If there is any malfunction, repair or replace suspected hose.
Voltage Inspection
1. Turn the engine switch to ON.
2. Monitor the MAP PID using the WDS or equivalent.
•If not as specified, perform the “Circuit Open/Short Inspection”.
MAP PID
2.1—2.5 V
3. Start the engine and warm up the engine completely.
4. Monitor the MAP PID using the WDS or equivalent at idle.
•If not as specified, perform the “Circuit Open/Short Inspection”.
MAP PID
2.1—2.5 V
Circuit Open/Short Inspection
1. Inspect for open/short circuit in the following
wiring harnesses.
•If there is open/short circuit, repair or replace
wiring harnesses.
Open circuit
•Power circuit
—Boost sensor terminal C and PCM terminal 90
•Signal circuit
—Boost sensor terminal B and PCM terminal 36
•GND circuit
—Boost sensor terminal A and PCM terminal 91
Short circuit
•Power circuit
—Boost sensor terminal C and PCM terminal 90 to GND
•Signal circuit
—Boost sensor terminal B and PCM terminal 36 to power circuit
—Boost sensor terminal B and PCM terminal 36 to GND
End Of Sie
BOOST SENSOR
HARNESS SIDE CONNECTOR
A
B C
A6E40702048

CONTROL SYSTEM
F2–79
F2
FUEL PRESSURE SENSOR INSPECTIONA6E404013015201
Note
•Perform the following test only when directed.
Voltage Inspection
1. Start the engine and warm up the engine completely.
2. Measure the voltage between fuel pressure sensor terminals A and B using a voltmeter at idle.
•If not as specified, perform the “Circuit Open/Short Inspection”.
—If there is no open/short circuit, replace the common rail.
Specification
1.4—1.7 V
3. Turn off the engine and wait three minutes.
4. Turn the engine switch to ON.
5. Measure the voltage between fuel pressure
sensor terminals A and B using a voltmeter.
•If not as specified, perform the “Circuit Open/
Short Inspection”.
—If there is no open/short circuit, replace
the common rail.
Specification
0.9—1.1 V
CIrcuit Open/Short Inspection
1. Inspect for open/short circuit in the following
wiring harnesses.
•If there is open/short circuit, repair or replace wiring harnesses.
Open circuit
•Power circuit
—Fuel pressure sensor terminal C and PCM terminal 90
•Signal circuit
—Fuel pressure sensor terminal B and PCM terminal 61
•GND circuit
—Fuel pressure sensor terminal A and PCM terminal 91
Short circuit
•Power circuit
—Fuel pressure sensor terminal C and PCM terminal 90 to GND
•Signal circuit
—Fuel pressure sensor terminal B and PCM terminal 61 to power circuit
—Fuel pressure sensor terminal B and PCM terminal 61 to GND
End Of Sie
FUEL PRESSURE SENSOR
HARNESS SIDE CONNECTOR
A
B C
A6E40702049

F2–80
CONTROL SYSTEM
CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATIONA6E404018200201
Caution
•When foreign material, such as iron chips, gets on the CMP sensor, it can cause abnormal output
from the sensor because of flux turbulence and adversely affect engine control. Be sure there is
no foreign material on the CMP sensor when replacing.
•Do not forcefully pull the wiring harness of the CMP sensor. Doing so will break the harness.
1. Disconnect the negative battery cable.
2. Remove the engine cover.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
O-ring Installation Note
1. Apply engine oil to new O-ring thinly and install it
as does not damage.
End Of Sie
CAMSHAFT POSITION (CMP) SENSOR INSPECTIONA6E404018200202
Note
•Perform the following test only when directed.
Caution
•When foreign material, such as iron chips, gets on the CMP sensor, it can cause abnormal output
from the sensor because of flux turbulence and adversely affect engine control. Be sure there is
no foreign material on the CMP sensor when replacing.
•Do not forcefully pull the wiring harness of the CMP sensor. Doing so will break the harness.
Visual Inspection
1. Verify that the CMP sensor and the pulsar are free of any metallic shavings or particles.
•If any are found on the CMP sensor and the pulsar, clean them off.
Air Gap Inspection
1. Disconnect the negative battery cable.
2. Remove the gear cover.
3. Verify that clearance A between the CMP sensor
and the pulsar is within the specification.
•If not as specified, replace the CMP sensor.
Clearance A
0.5—1.5 mm {0.020—0.059 in}
1 CMP sensor installation bolt
2 CMP sensor
3 O-ring
(See F2–80 O-ring Installation Note)
N·m {kgf·cm, in·lbf}
3
127.8—10.8
{80—110, 69.1—95.5}
R
OILOIL
A6E40702050
CMP SENSOR
CLEARANCE A
PULSAR
A6E40702051

CONTROL SYSTEM
F2–81
F2
Resistance Inspection
1. Disconnect the negative battery cable.
2. Remove the engine cover.
3. Disconnect the CMP sensor connector.
4. Inspect the resistance between the terminals
under the following condition.
•If not as specified, replace the CMP sensor.
Specification
Circuit Open/Short Inspection
1. Inspect for open/short circuit in the following
wiring harnesses.
•if there is open/short circuit, repair or replace
wiring harnesses.
Open circuit
•CMP sensor terminal A and PCM terminal 81
•CMP sensor terminal B and PCM terminal 55
Short circuit
•CMP sensor terminal A and PCM terminal 81 to GND
•CMP sensor terminal B and PCM terminal 55 to GND
End Of Sie
CRANKSHAFT POSITION (CKP) SENSOR REMOVAL/INSTALLATIONA6E404018230201
Caution
•When foreign material, such as iron chips, gets on the CKP sensor, it can cause abnormal output
from the sensor because of flux turbulence and adversely affect engine control. Be sure there is
no foreign material on the CKP sensor when replacing.
•Do not forcefully pull the wiring harness of the CKP sensor. Doing so will break the harness.
1. Disconnect the negative battery cable.
2. Remove the crankshaft pulley. (See B2–9 TIMING BELT REMOVAL/INSTALLATION.)
3. Remove the lower timing belt cover. (See B2–9 TIMING BELT REMOVAL/INSTALLATION.)
4. Remove in the order indicated in the table.
5. Install in the reverse order of removal.
End Of Sie
TerminalAtmospheric
temperature (°C {°F})Resistance
(kilohm)
A—B 20 {68} 1.85—2.45
A
B
A6E40702052
1 CKP sensor installation bolt
2 CKP sensor
N·m {kgf·cm, in·lbf} 16—23 {1.6—2.4, 12—17}12
A6E40702053