2002 MAZDA 6 transmission

K2–74
AUTOMATIC TRANSAXLE
Evaluation of line pressure test
Stall Speed Test
1. Perform mechanical system test preparation. (See K2–72 Mechanical System Test Preparation.)
2. Connect a tachometer.
3. Start the engine.
4. Shift the selector lever to D range.
Caution
•Do not maintain WOT in any gear range for more than 5 seconds or transaxle damage will occur.
•If engine speed recorded by the tachometer exceeds maximum specified rpm, release the
accelerator pedal immediately. Clutch or band slippage is indicator.
5. Firmly depress the brake pedal with the left foot, and gently depress the accelerator pedal to the floor (WOT)
with the right.
6. When the engine speed no longer increases, quickly read the engine speed and release the accelerator pedal.
7. Shift the selector the to N position and let the engine idle for 1 minute or more to cool the ATF.
8. Perform stall tests for the remaining ranges and position in the same manner.
•R position
•Mrange (1GR, 2GR)
Engine stall speed
ATF temperature : 60—70 °C {140—158 °F}
Turn off all electrical loads
2,200—2,600 rpm
9. Turn off the engine.
Evaluation of stall test
Condition Possible cause
IdleBelow specificationLow pressure in all rangesWorn oil pump
Poor operation of each solenoid
Fluid leaking from oil strainer, oil pump, pressure regulator
valve, torque converter relief valve, and/or pressure relief valve
Pressure regulator valve or pilot valve sticking
Damaged pressure regulator valve spring or pilot valve spring
Low pressure in D and M
rangeFluid leaking from hydraulic circuit of low clutch
Low pressure in R position
onlyFluid leaking from hydraulic circuit of reverse clutch
Fluid leaking from hydraulic circuit of low and reverse brake
clutch
Above specification High pressure in all rangesThrottle position sensor out of adjustment
TFT sensor malfunction
Poor operation of shift solenoid
Pilot valve sticking
Pressure reducing valve or plug sticking
Stall Below specification Low pressure in all rangesThrottle position sensor out of adjustment
Pressure control solenoid malfunction
Poor operation of shift solenoid
Pilot valve sticking
Pressure reducing valve or plug sticking
Condition Possible cause
Above specificationIn all forward ranges and R
positionInsufficient line pressure
Worm oil pump
Poor operation of low clutch
Poor adjustment or malfunction of TR switch
Oil leaking from oil pump, control valve, and/or transmission
case
Pressure regulator valve or pilot valve sticking
In all forward ranges Low clutch slippage
Low one-way clutch slippage
Reduction one-way clutch slippage
In R positionLow and reverse brake slippage
Reverse clutch slippage
Reduction brake slippage
Below specificationIn all forward ranges and R
positionEngine out of tune
One-way clutch slippage within torque converter

ELECTRONIC 4WD CONTROL SYSTEM
M–9
M
End Of SieELECTRONIC CONTROL COUPLINGA6E632227100202Outline
Features
•An electromagnetic clutch, which operates smoothly due to the lack influence from the front and rear wheel
traction force, has been adopted for the electronic control coupling system.
•The construction of the coupling enables the torque formed by the pilot clutch to be amplified by the cam
mechanism, thus allowing the main clutch to obtain a high degree of torque. Due to this, size and weight
reduction of the component parts has been achieved.
Construction
•The electronic control coupling basically consists of an electromagnetic clutch, a cam mechanism and a torque
transmission system.
•The electromagnetic clutch consists of a 4WD solenoid (electromagnetic coil), rear-housing that forms a
magnetic path, pilot clutch, and armature. The cam mechanism consists of a pilot cam, balls, and main cam.
The torque transmission system consists of a main clutch and hydraulic oil (ATF).
.
9
8
7
5
43
10
13
1112
6
12
A6E63222003
1 Front wheel side
2 Rear wheel side
3 Torque transmission system
4 Electromagnetic clutch
5 Rear housing
6 4WD solenoid (Electromagnetic coil)
7 Cam mechanism8Ball
9 Main clutch
10 Main cam
11 Armature
12 Pilot clutch
13 Pilot cam

ELECTRONIC 4WD CONTROL SYSTEM
M–11
M
4WD solenoid control current is ON
•When the 4WD solenoid control current is ON, current flows from the 4WD CM to the 4WD solenoid, and the
coupling operates in the following manner.
1. Magnetic flux forms at the electromagnetic coil of the 4WD solenoid.
2. Due to the magnetic flux in the armature, the pilot clutch is suctioned towards the magnetic coil side and
made to engage. This causes frictional torque to generate in the pilot clutch.
3. The torque is transmitted to the pilot cam, which is engaged with the pilot clutch.
4. A rotational difference is created between the pilot cam and the main cam. Due to this relative torsion, the
cam mechanism operates, transmitting torque from the pilot cam to the ball and then to the main cam. In
this way, the push force exerted on the main clutch is amplified.
5. As the main clutch engages, the drive torque from the front wheels is transmitted to the rear wheels.
•The amount of push force exerted on the main clutch by the main cam (that is, the strength of the drive torque
transmitted to the rear wheels) changes in accordance with the proportion of the force acting upon the pilot
cam, engaged with the pilot clutch. Therefore, by changing the periodicity of the electric current from the 4WD
CM to the 4WD solenoid (ON/OFF rate of the 4WD solenoid = force acting on the pilot cam), the module
controls the transmission of drive torque to the rear wheels.
.
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98
75
4
3
10
11
6
12
56
7
12
A6E63222005
1 Main clutch
2Pilot clutch
3 4WD solenoid (Electromagnetic coil)
4 4WD control modure (4WD CM)
5Main cam
6Pilot cam7Ball
8Armature
9 Drive torque
10 Magnetic flux
11 Input
12 Output

ELECTRONIC 4WD CONTROL SYSTEM
M–13
M
4WD CONTROL MODUREA6E632227100205Function
•The 4WD control modure (4WD CM) calculates the optimal amount of torque distribution for the rear wheels
and outputs a corresponding electric current to the electronic control coupling (4WD solenoid). This calculation
is based on the throttle angle, four-wheel speed, engine speed, selector lever position, and other related input
signals, matched with the vehicle driving and road surface conditions.
Functions
Construction
•The 4WD CM is installed to the left of the brake pedal (clutch pedal position).
Block diagram
.
Function name Contents
4WD system control
function•Based on each input signal, the electronic control current sent to the electronic control coupling
(4WD solenoid) is optimally controlled.
Diagnostic system•If the self-diagnostic system detects a malfunction, the 4WD warning light illuminates to alert
the driver, and at the same time the system suspends control or performs other measures to
prevent a loss of driving stability and protect the system.
•The detected malfunction is stored as a DTC in the 4WD CM.
987
5
43
10
19
18
17
15
16
14
131112
6
1
2
A6E63222008
1Front
2PCM
3TCM
4 DSC HU/CM
5 4WD control modure (4WD CM)
6 4WD solenoid
7Transaxle
8Transfer
9 Propeller shaft
10 Front drive shaft11 Pilot clutch/pilot cam
12 Ball/main cam
13 Main clutch
14 Electronic control coupling
15 Rear differential
16 Rear drive shaft
17 Torque transmission path
18 Electric signal path
19 Solenoid activation

M–68
ELECTRONIC 4WD CONTROL SYSTEM
COUPLING COMPONENT REMOVAL/INSTALLATIONA6E6322271002141. Drain the differential oil into a container.
2. Remove the after silencer, presilencer, and the catalytic converter. (See F1–30 EXHAUST SYSTEM
REMOVAL/INSTALLATION.)
3. Remove the propeller shaft. (See L–5 PROPELLER SHAFT REMOVAL/INSTALLATION.)
4. Remove in the order indicated in the table.
5. Install in the reverse order of removal.
6. Add differential oil.
.
Coupling Component Removal Note
1. Support the coupling unit with a transmission jack.
2. Cut away the coupling unit using an oil pan seal
cutter.
Coupling Component Installation Note
Note
•Clean away the old sealant before applying the new sealant.
•Install the coupling unit within 10 minutes after applying sealant.
•Allow the sealant to set at least 30 minutes after installation before filling the differential with the specified
oil.
3
12
SEALANTSEALANT
74.5—104.9
{7.6—10.6, 55.0—77.3}22.6—26.4
{2.4—2.6, 16.7—19.4}
N·m {kgf·m, ft·lbf}
A6E63222106
1 4WD solenoid connector
2Bolt3 Coupling component
(See M–68 Coupling Component Removal Note)
(See M–68 Coupling Component Installation Note)
OIL PAN
SEAL CUTTER
A6E63222107

MULTIPLEX COMMUNICATION SYSTEM
T–5
T
End Of Sie
Cruise main indicator light
conditions (MZR-CD (RF
Turbo))OUT–––IN
Cruise set indicator light
conditions (MZR-CD (RF
Turbo))OUT–––IN
Desired gear/
selector lever
positionFN4A-EL OUT–IN–IN
JA5AX-EL IN OUT IN IN IN
ECT OUT IN–IN
Engine control condition OUT–IN––
Engine displacement OUT–IN––
Engine loss torque (except
MZR-CD (RF Turbo))OUT IN–––
Engine speed OUT IN IN IN IN
Engine torque (except
MZR-CD (RF Turbo))OUT IN–––
Fuel injection information OUT–IN––
Fuel type and delivery OUT–IN––
Gear position IN OUT IN IN IN
Generator warning light
conditions (except MZR-
CD (RF Turbo))OUT–––IN
Glow indicator light
condition (MZR-CD (RF
Turbo))OUT–––IN
HOLD indicator light
conditions (FN4A-EL)OUT–––IN
Idle speed up request IN OUT–––
MIL condition (except
MZR-CD (RF Turbo))OUT–––IN
MIL indicate request IN OUT–––
Number of cylinders OUT–IN––
Racing select
determinationIN OUT–––
TCC condition IN OUT–––
Tire circumference (front/
rear)OUT–IN––
Torque reduction inhibit OUT IN IN––
TP OUTINININ–
Transmission/axle type OUT–IN––
Travelled distanceIN–OUT––
IN OUT––IN
OUT–––IN
Torque
reduction
requestJA5AX-EL IN OUT–––
except
JA5AX-ELIN–OUT––
Turbine speed IN OUT–––
Upper torque limit IN OUT–––
Vehicle speedOUT–––IN
IN OUT–––
Wheel speed (front left/
front right/rear left/rear
right)IN IN OUT IN–
OUT–––IN
4WD system operating
condition (warning light
information)–––OUT IN SignalMultiplex module
PCM TCMABS (ABS/TCS)
HU/CM or
DSC HU/CM4WD control
moduleInstrument
cluster