2002 MAZDA 6 brake sensor

F2–202
TROUBLESHOOTING
NO.14 POOR FUEL ECONOMYA6E408018881216
Diagnostic Procedure
14 POOR FUEL ECONOMY
DESCRIPTION•Fuel economy is unsatisfactory.
POSSIBLE
CAUSE•Incorrect idle speed
•A/C system improper operation
•Intake -air system clogging or restriction
•Engine cooling system malfunction
•Poor fuel quality
•Improper coolant level
•Erratic signal from CKP sensor
•Erratic signal from CMP sensor
•Fuel pressure sensor or related circuit malfunction
•ECT sensor or related circuit malfunction
•Boost sensor or related circuit malfunction
•Accelerator position sensor or related circuit malfunction
•Incorrect adjustment idle switch
•MAF/IAT sensor or related circuit malfunction
•IAT sensor No .2 or related circuit malfunction
•VSS or related circuit malfunction
•Turbocharger malfunction
•Charge air cooler malfunction
•Low engine compression
•Improper valve timing
•Exhaust system and/or catalyst converter clogging
•Incorrect fuel injection timing
•Fuel injector malfunction
•Supply pump malfunction
•Fuel leakage
•Fuel line clogging or restriction
•Fuel filter clogging or restriction
•Brake dragging
•EGR system malfunction
•Vacuum leakage
•Clutch slippage
•Variable boost control (VBC) system malfunction
•Coolant heater system malfunction
Warning
The following troubleshooting flow chart contains the fuel system diagnosis and repair
procedures. Read the following warnings before performing the fuel system services:
•Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep
sparks and flames away from fuel.
•Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injury or death
and damage. Fuel can also irritate skin and eyes. To prevent this, always complete “BEFORE
REPAIR PROCEDURE” and “AFTER REPAIR PROCEDURE” described in this manual.
STEP INSPECTION RESULTS ACTION
1 Inspect for following:
•Fuel quality (e.g.: including water
contamination, winter/summer blend)
•Fuel line/fuel filter clogging and/or restriction
•Fuel line leakage
•Intake-air system restriction
•Exhaust system and/or catalyst converter
restriction
•Charge air cooler condition (restriction or
damaged)
•Vacuum leakage
Are all items okay?Yes Go to next step.
No Service as necessary.
Repeat Step 1.
2 Is brake system functioning properly? Yes Go to next step.
No Inspect for cause.

F2–204
TROUBLESHOOTING
End Of Sie
14 Measure gap between CKP sensor and teeth of
pulse wheel.
Specification
1.5—2.5 mm {0.059—0.098 in}
Is gap within specification?Yes Go to next step.
No Adjust CKP sensor position.
15 Visually inspect CMP sensor and teeth of pulse
wheel.
Are CMP sensor and teeth of pulse wheel okay?Yes Inspect following PIDs:
(See F2–65 PCM INSPECTION)
•ECT
•IAT
•MAF
•MAP
•RPM
•VSS
If PID value is not as specified, repair or replace
malfunctioning parts.
If PID value is okay, go to next step.
No Replace malfunctioning parts.
16 Inspect timing belt for following:
•Chipping of gear teeth
•Low tension
•Breakage damage or cracks
Is timing belt okay?Yes Inspect following:
•Clutch slippage
•CKP sensor
•Boost sensor and related circuit
•Brake system for dragging
•Coolant heater system
•Glow system
If okay, remove and inspect supply pump.
No If timing is incorrect, adjust valve timing.
If timing belt is not okay, replace timing belt.
17 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. (See F2–64 PCM REMOVAL/INSTALLATION) STEP INSPECTION RESULTS ACTION

K2–4
AUTOMATIC TRANSAXLE
Bold frames:New specifications
End Of Sie
OUTLINEA6E571401030201•Adopted new JA5AX-EL automatic transaxle.
•Newly designed FF type five-speed automatic transaxle.
—Use of 3 sets of planetary gears, and a wider gear ratio setting realizes improvement of acceleration-from-
standing-start performance, fuel economy, and quietness. Also, by placement of two sets of planetary gears
in parallel with one set, the automatic transaxle is more compact.
•Adopted 2-4 brake clutch.
—Adopted a wet-type, multi-plate 2-4 brake clutch instead of the 2-4 brake band used in the past, for
smoother gear switching performance.
•Adopted centrifugal balance clutch
—The newly adopted centrifugal balance clutch pushes the clutch piston forcefully to low and high clutch by
centrifugal hydraulic pressure for smoother gear switching with batter response.
•Adopted controller area network (CAN)
—By adopting CAN, The TCM is always in contact with other computers in the car and controls the automatic
transaxle properly. This has also made troubleshooting diagnosis easier for the entire vehicle.
•Solenoid, sensor
—Adoption of four duty-type solenoids, five ON-OFF type solenoids, and three revolving sensors realizes
finer, more expedient control of gear shifting performance.
•Adoption of revers inhibit control
—If the reverse position is selected by mistake while driving in forward motion, the reverse inhibit control
system will cancel the operation electronically and set the position to neutral as a safety enhancement.
Outline of Operation
•The operation of the electronic automatic transaxle is classified into three systems: the electronic control
system, the hydraulic pressure control system, and the powertrain system (includes the torque converter
system.)
Electronic control system
•According to the signals from the switches and sensors in the input system, the TCM outputs the signal
which matches the present driving condition to the ON/OFF type solenoids and the duty-cycle type
solenoids in the hydraulic pressure control system.
Hydraulic pressure control system
•According to the signals from the TCM, each solenoid operates to switch the hydraulic passages in the
control valve body and controls the clutch engagement pressure.
•The line pressure is adjusted by the duty-cycle type pressure control solenoid. The hydraulic passages
are switched by the ON/OFF type solenoids and the clutch engagement pressure is controlled by the
duty-cycle type solenoids.
Powertrain system
•The driving force from the engine is transmitted through the torque converter to the transaxle.
•The transmitted driving force operates each clutch and brake according to the clutch engagement
pressure from the duty-cycle type solenoid, and the planetary gears change the gear ratio to the
optimal driving force. The changed driving force is transmitted through the differential to the axle shaft
and then the tires.
AUTOMATIC TRANSAXLE

K2–8
AUTOMATIC TRANSAXLE
ELECTRONIC CONTROL SYSTEM STRUCTURAL VIEWA6E571401030203•The TCM control the automatic transaxle operations. The TCM outputs a control signal to the transaxle
according to the signal from other sensors and/or switches.
.
9
8
7
5
4
3
1
2
1011
6
1
A6E5714W010
1TCM
2PCM
3Selector lever
4 M range switch
5 Up switch
6 Down switch7DLC-2
8 Brake light switch
9 AT warning light
10 Selector indicator light
11 Gear position indicator light

K2–10
AUTOMATIC TRANSAXLE
AUTOMATIC TRANSAXLE CONTROL SYSTEM WIRING DIAGRAMA6E571401030204
.
1W1P
2P
2S
2T
2X
2G
2D
2J
2M
1C
1Y 2W 2Z
2Y
2V
2U 1Z
1T
2B
1U
2C
1S
1H
1F
1B
1M
1V
1N
2F
1K
1X 1AA2AA
9
8
7
5
4
3
1
2
10
19
18
17
15
16
14
13
11
12
20
6
29
28
2725
26
24
23
21
22
A6E5714W008
1TCM
2 R position (TR switch)
3 D range (TR switch)
4 N position (TR switch)
5 P position (TR switch)
6 Brake switch
7 M range switch
8 Up switch9 Down switch
10 Selector lever
11 Cruise control module (In cruise actuator)
12 TFT sensor
13 VSS
14 Input/turbine speed sensor
15 Intermediate sensor
16 Pressure control solenoid

AUTOMATIC TRANSAXLE
K2–11
K2
End Of SieAUTOMATIC TRANSAXLE BLOCK DIAGRAMA6E571401030205
.
17 2-4 brake solenoid valve
18 High clutch solenoid valve
19 TCC solenoid valve
20 Shift solenoid A
21 Shift solenoid B
22 Shift solenoid C
23 Reduction timing solenoid valve24 Neutral shift solenoid valve
25 CAN_L
26 CAN_H
27 Instrument cluster
28 PCM
29 ABS HU/CM or DSC HU/CM
543
12
A6E5714W012
1 Input
2Output
3TCM
4PCM
ABS HU/CM or DSC HU/CM
TFT sensor
Input/turbine speed sensor
Intermediate sensor
VSS
TR switch
M range switch
Up switch
Down switch
Brake switch
Cruise control module5 Pressure control solenoid
2-4 brake solenoid valve
High clutch solenoid valve
TCC solenoid valve
Shift solenoid A
Shift solenoid B
Shift solenoid C
Reduction timing solenoid valve
Neutral shift solenoid valve
AT warning light

K2–12
AUTOMATIC TRANSAXLE
Electronic Control Item and Control
Component Description (Electronic Control)
Control item Contents
Shift control•Detects engine load condition and vehicle speed. Shifts to the best gear
position according to the programmed automatic shift diagram.
Line pressure control•Generates line pressure matching the engine load condition and driving
conditions. Optimizes line pressure for each shift. When the ATF
temperature is low, automatically optimizes line pressure for quick clutch
engagement.
Revers inhibition control•When the shift lever is shifted to R position while the vehicle is running
forward at approx. 30 km/h{19 mph} or more, the TCM turns the neutral
shift solenoid valve on and drains the low and reverse brake hydraulic
pressure. Due to this, the transaxle shifts to neutral.
Shift transient control•Adjusts transient hydraulic pressure according to engine load and
vehicle driving conditions when shifting using the pressure control
solenoid, 2-4 brake solenoid valve, the high clutch solenoid valve, and
each accumulator control valve.
•Temporarily lowers engine torque during shift (up and down) to improve
shift feel
•The lock timing for the reduction brake band is controlled by the control
of the reduction timing solenoid valve ON/OFF timing.
•The lock timing for the clutch brake is controlled by the control of shift
solenoid A, B, and C ON/OFF timing.
Feedback control•Corrects clutch engagement pressure and timing on drain side to
compensate for changes in engine performance and changes in
transaxle
TCC control•Controls TCC according to the programmed TCC points
N-D select control•When a driving range is selected from P/N, the fuel injection amount is
controlled to prevent fluctuation in engine speed.
Slope mode control•Changes the shift point to prevent frequent shifting up/down when
climbing hills
OBD system•Detects and/or memorizes failure of input/output part and transaxle
condition
Part name Function
Input system TR switch•Detects selector lever ranges/positions
Input/turbine speed sensor•Detects reverse clutch drum revolution speed
Intermediate sensor•Detects output gear revolution speed
Vehicle speedometer sensor•Detects parking gear revolution speed
TFT sensor•Detects the ATF temperature
Brake switch•Detects the brake pedal depressed
Cruise control module (in cruise actuator)•When the cruise control is in use, the signal detects when the
difference between the target speed and actual speed
exceeds specification
M range switch•Detects selector lever shifted M range
Up switch•Detects up shift in M range
Down switch•Detects down shift in M range
CAN signal Throttle position signal•Input throttle opening angle from PCM
Engine torque signal
(without torque down)•Input engine torque from PCM
Engine torque signal (with
torque down)•Input engine torque from PCM
Engine torque signal (loss
torque)•Input engine loss torque from PCM
Torque reduced signal•Detects signals indicating torque down availability
Engine coolant
temperature signal•Input engine coolant temperature from PCM
Engine speed signal•Input engine speed from PCM
Battery OFF signal•Detect negative battery cable disconnected
4 wheel speed signal•Input wheel speed from ABS HU/CM or DSC HU/CM

AUTOMATIC TRANSAXLE
K2–13
K2
End Of SieAUTOMATIC TRANSAXLE DEVICE RELATIONSHIP CHARTA6E571401030206
Output system ON/OFF
typeShift solenoid A•Switches ON and OFF based on electric signals from the
TCM, changes hydraulic circuit to control shifting
Shift solenoid B•Switches ON and OFF based on electric signals from the
TCM, changes hydraulic circuit to control shifting
Shift solenoid C•Switches ON and OFF based on electric signals from the
TCM, changes hydraulic circuit to control shifting
Reduction timing solenoid
valve•Switches ON and OFF based on electric signals from the
TCM, changes hydraulic circuit to control shifting
Neutral shift solenoid valve•Switches ON and OFF based on electric signals from the
TCM, changes hydraulic circuit to control shifting
Duty type
Pressure control solenoid•Switches ON and OFF based on electric signal (duty signals)
from the TCM adjusts line pressure to match driving
conditions
2-4 brake solenoid valve•Switches ON and OFF based on electric signal (duty signals)
from the TCM adjusts line pressure to match driving
conditions
High clutch solenoid valve•Switch ON and OFF based on electric signal (duty signals)
from the TCM adjusts line pressure to match driving
conditions
TCC solenoid valve•Switch ON and OFF based on electric signal (duty signals)
from the TCM to control TCC
CAN signal Reduce torque signal•Sends signals to the PCM during shifting
Range signal•Output transaxle load condition to PCM
Turbine speed signal•Output turbine speed to PCM
ATF temperature signal•Output ATF high temperature signal to PCM
TCC signal•Output TCC signal to PCM
Racing select signal•Requests fuel cut when selector lever is shifted during racing
MIL indicate request signal•Requests MIL illumination when failure is detected by
diagnosis function
AT warning light request
signal•Requests AT warning light indication when failure is detected
by diagnosis function for ATX Part name Function
ComponentControl item
Shift
controlLine
pressure
controlReverse
inhibition
controlShift
transient
controlFeedbac
k controlTCC
controlN-D
select
controlSlope
mode
controlOBD
system
Input
TR switch XXXXXXX X
Input/turbine
speed sensorX XXXXXX
Intermediate
sensorXXX X
Vehicle
speedometer
sensorXXXXXXXXX
TFT sensor XX XXXX X
Brake switch X X X
Cruise control
module (4GR
inhibit signal)XX
M range switch X X
Up switch X X
Down switch X X