ELECTRONIC 4WD CONTROL SYSTEM
M–7
M
OUTLINEA6E632227100201Features
Improved off-road mobility, handling stability, operability, fuel economy and marketability
•An electronic 4WD control system, which automatically optimizes traction distribution to the front and rear
wheels, has been adopted.
Improved serviceability
•A self-diagnostic function has been adopted for the electronic 4WD control system.
Electronic 4WD control system outline
•The newly adopted electronic 4WD control system automatically and optimally controls drive torque distribution
for the front and rear wheels. Due to this off-road mobility, driving stability and fuel economy are improved.
•Based on the input signals from each sensor, the 4WD control modure (4WD CM) determines vehicle driving
and road conditions, and controls output current to the electronic control coupling (4WD solenoid) inside the
rear differential. This control allows for optimal distribution of the drive torque from the engine to the rear
wheels.
•Also, the 4WD CM automatically controls the 4WD, greatly reducing the load on the driver and improving
operability.
Structural view
.
ELECTRONIC 4WD CONTROL SYSTEM
87
5
4
3
6
9
8
7
5
4
3
10
6
1
2
9
10
A6E63222001
1L.H.D.
2 R.H.D.
3 4WD warning light
4 4WD control modure
5 DSC HU/CM6PCM
7TCM
8 Electronic control coupling (4WD solenoid)
9 Differential oil temperature sensor
10 Rear differential
ELECTRONIC 4WD CONTROL SYSTEM
M–15
M
Operation
Normal control
•When starting off or accelerating during straight-ahead driving, torque transmitted to the rear wheels is
optimally controlled to ensure sufficient acceleration performance. Due to this, standing-start and acceleration
performance is improved.
•Also, in order to improve fuel economy when driving at a stable, consistent speed, torque transmitted to the
rear wheels is damped, and rear-wheel drive is controlled to maintain it close to that of the front wheels.
Tight cornering control
•When the 4WD CM determines, based on the four-wheel speed signal, that the vehicle is in tight cornering, it
reduces the torque transmitted to the rear wheels to avoid tight corner braking characteristics.
Integrated DSC control
•If a signal from the DSC HU/CM input to the 4WD CM indicates that ABS control is activated, the module
controls the torque transmitted to the rear wheels to prevent undue influence on ABS control.
•Also, when a coupling torque request signal is received from the DSC HU/CM, the module controls the torque
transmitted to the rear wheels to match the amount of requested torque.
Other control
•In case the rear differential oil temperature exceeds the specified amount, or when there is an unusually large
variation in the rotation speed of the front and rear wheels (ex. when trying to get unstuck), control is
temporarily suspended in order to protect the 4WD system. When this occurs the 4WD warning light flashes to
indicate the situation to the driver.
End Of Sie
CONTROLLER AREA NETWORK (CAN)A6E632227100207Outline
•The 4WD CM transmits/receives information using the CAN system. See Section T for detailed information
regarding the CAN system.
Operation
Transmitted information
•Coupling torque
•4WD system operating condition (warning light information)
Received information
•Four-wheel speed
•Throttle opening angle
•Engine speed
•ABS/DSC operating condition
•Gear position
•Selector lever position
•Coupling torque request
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GENERAL PROCEDURES
M–21
M
PRECAUTION (FRONT AND REAR AXLE)A6E631001018201Wheel and Tire Removal/Installation
1. The removal and installation procedures for the wheels and tires are not mentioned in this section. When a
wheel is removed, tighten it to 88—118 N·m {9.0—12.0 kgf·m, 65.0—87.0 ft·lbf}
Brake Line Disconnection/Connection
Caution
•Brake fluid will damage painted surfaces. If brake fluid gets on a painted surface, wipe it off
immediately.
1. Tighten the brake pipe flare nut using the SST (49 0259 770B). Be sure to modify the brake pipe flare nut
tightening torque to allow for use of a torque wrench-SST combination.
2. If any brake line has been disconnected any time during the procedure, add brake fluid, bleed the brakes, and
inspect for leakage after the procedure has been completed.
Suspension Arm Removal/Installation
1. Tighten any part of the suspension that uses rubber bushings only after vehicle has been lowered and
unloaded.
Note
•Unloaded: Fuel tank is full. Engine coolant and engine oil are at specified level. Spare tire, jack, and tools
are in designated position.
Connector Disconnection
1. Disconnect the negative (-) battery cable before disconnecting connectors.
Electronic Control 4WD System Parts
1. After servicing the electronic control 4WD system parts, verify that no DTC has been stored. Clear any DTCs
remaining in the memory.
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GENERAL PROCEDURES
P–8
DYNAMIC STABILITY CONTROL
End Of SieCOMBINE SENSOR (FORWARD-G SENSOR)A6E692067650202Function
•The forward-G sensor is integrated with the combine sensor to detect and calculate the vehicle forward-G force
and change in voltage to the DSC HU/CM.
Structure/Operation
•The drive train of 4WD vehicles delivers driving force to all four wheels, and due to this interlocking, the speed
of all wheels during braking is the same. When driving on road surfaces with especially low m (friction
coefficient), it is difficult to estimate the vehicle speed based on the wheel speed, and DSC braking becomes
unreliable. (For 2WD vehicles, the front and rear wheels are independent, so it is possible to accurately
estimate the vehicle speed by measuring the difference between the rotation speeds of the front and rear tires.)
A forward-G sensor has been installed to overcome this situation. When braking, the change in G-force is
detected, and the road surface m is judged (low m, high m), enabling a correction of the vehicle speed
estimation.
•The output voltage characteristic for the combine sensor is 2.5 V when the vehicle is standing still, and
changes accordingly as forward-G is formed.
•Forward-G is formed when the sensor detects an inertial force created by, and in proportion to, a G- force
acting on a silicon detection component.
.
End Of Sie
CONTROLLER AREA NETWORK (CAN)A6E692067650203•ABS (ABS/TCS) or DSC HU/CM transmit/receive information through CAN. Due to the addition of TCM, 4WD
CM, and the MZR-CD (RF Turbo) engine model, the following information has been changed. For detailed
information on CAN, see the “CONTROLLER AREA NETWORK.” (See T–3 OUTLINE.)
Transmitted Information
•Coupling torque request (to 4WD CM)
•DSC operating condition (to 4WD CM)
Received Information
•Coupling torque (from 4WD CM)
•Shift position (from TCM)
•Fuel injection information (only MZR-CD (RF Turbo), from PCM)
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(V)
2.5
-14.70
+14.7(m/s
2)
45
3
6
2
1
A6E6920W201
1 External view
2 Front of vehicle
3 Output voltage characteristic4 Deceleration
5 Forward-G
6 Acceleration
ON-BOARD DIAGNOSTIC
P–9
P
OUTLINEA6E697043000201•The operation of the on-board diagnostic system for ABS (ABS/TCS) or DSC is the same as that of the current
Mazda6 (GG) L8, LF, L3 engine 2WD model, except for the following. (See Mazda6 Training Manual
3359-1*-02C.)
— Due to the addition of the 4WD model, DTCs and PID data monitor has been added.
—Due to the addition of the MZR-CD (RF Turbo) engine model, the DTC C1119 fail-safe function and the
detection condition have been changed.
Fail-safe Function
Fail-safe function table
*1: When engine speed signal through CAN is out of specification, the light illuminates.*2: When engine speed signal through CAN is out of specification, the system is suspended.*3: When engine speed signal value through CAN is invalid, only brake TCS is available.*4: When fuel injection information through CAN is out of specification or invalid, only brake TCS is available.*5: When engine speed signal value through CAN is invalid, only brake DSC is available.*6: When the engine control system has a malfunction, only brake DSC is available.
PID/DATA Monitor Table
End Of Sie
ON-BOARD DIAGNOSTIC
Malfunc-
tion
locationDTC Fail-safe function
WDS
or
equiva-
lentWarning light illumination condition Control condition
ABS
warning
lightBRAKE
system
warning
light
(when
parking
brake is
released)DSC
(TCS)
OFF lightDSC
(TCS)
indicator
light ABS
controlEBD
controlTCS
controlDSC
controlBrake
assist
control
PCM and/
or engine
speed
signal lineC1119Not
Illuminated Not
Illuminated Not
Illuminated
*1Illuminated Available AvailableAvailable*2, *3, *4Available*2, *5, *6Available
Combine
sensor
(forward-
G) lineC1949
Illuminated Not
Illuminated Illuminated IlluminatedNot
availableAvailable—Not
availableNot
available
C1950
CAN line U2511Not
Illuminated Not
Illuminated Not
Illuminated Illuminated Available Available—Available Available
PID name input/output part Operation/unit
ACCLMTR Accelerometer ACCELERATION
P–26
ON-BOARD DIAGNOSTIC
DTC C1119A6E697067650202
DTC C1119 Engine control system, torque reduction inhibit signal line
DETECTION
CONDITION•Engine RPM information through CAN is out of specification
•Throttle information through CAN is out of specification
•Fuel injection information through CAN is invalid or out of specification (for MZR-CD (RF Turbo) only).
•Received control inhibition signal from PCM through CAN.
POSSIBLE
CAUSE•Malfunction of PCM
•Malfunction of CAN
PCM
PCM HARNESS SIDE CONNECTOR (L3, L8, LF)
2U2R
CAN LINEABS (ABS/TCS): O
DSC: AG
ABS (ABS/TCS): R
DSC: AF
AQ
B
CDE
FG
HI
J DSC HU/CU HARNESS SIDE CONNECTOR
A
C E
H
K N Q
T
W Z AC AF
F I L O R U X
AA AD AG
G
J
M P S
V
Y AB
AE AHB
DKN
T
WZ
AC
AFLO
RU
XAA
ADAGMP
SV
YAB
AEAH
SST (49 G066 001) CONNECTOR
AD AC AB AAA Q
B R
C S
D T
E U
F V
G W
H X
I Y
J L M
O PZ ABS (ABS/TCS) HU/CM HARNESS SIDE CONNECTOR
ADAC
ABAA
A
B
C D
E
F G
H
I J
L M
O P
Q
R S
T
U V
W
X Y
Z
SST (49 G066 004) CONNECTOR
PCM HARNESS SIDE CONNECTOR (MZR-CD (RF TURBO))
13
39
L8, LF, L3: 2U
MZR-CD
(RF TURBO): 13
L8, LF, L3: 2R
MZR-CD
(RF TURBO): 39
OUTLINE
R–3
R
SPECIFICATIONSA6E740201013203
*1: Engine coolant and engine oil are at specified level. Fuel is full. Spare tire, jack and tools are in designated position.
*
2: Difference between left and right must not exceed 1 °30'.*3: Distance between wheel center and fender brim is following. 4SD and 5HB front: 402 mm {15.82 in} (reference
value) 4SD and 5HB rear: 401 mm {15.78 in} (reference value), WGN (2WD) front: 405 mm {15.94 in}
(reference value) WGN (2WD) rear: 407 mm {16.02 in} (reference value)
Bold frames: New specifications
End Of Sie
Item Specification
New Mazda6 Current
Mazda6
GG (4SD, 5HB) GY (WGN 2WD) GY (WGN 4WD) GG (4SD, 5HB)
Engine type LF, MZR-CD
(RF Turbo) L8, LF, L3,
MZR-CD (RF Turbo) L3 L8, LF, L3
Fr o nt
suspension Type High-mount double wishbone (with double-pivoted lower arm(s))
Spring type Coil spring
Shock absorber type
Cylindrical, double-acting
(Low-pressure gas charged with rebound spring)
Stabilizer Type Torsion bar
Diameter (mm {in}) 23 {0.91}
Wheel
alignment
(Unloaded)*
1
Total toe-in (mm {in}) Tire: 2
±4 {0.08 ±0.16}, Rim inner: 1 ±3 {0.04 ±0.12}
(degree) 0 °11 ′±0°22 ′
Maximum
steering
angle inner
18 inch wheel specification vehicles: 36
°±3°
Except for above: 39 °±3°
outer 18 inch wheel specification vehicles: 30
°±3°
Except for above: 31 °±3°
Caster
angle*
2
(reference
value) normal 3
°47 ′±1° 3°40 ′±1° 3°35 ′±1° 3°47 ′±1°
elevated*33 °42' ±1° 3°35 ′±1° —3 °42' ±1 °
Camber
angle*
2
(reference
value) normal –0
°17 ′±1° –0°15 ′±1° –0°08 ′±1° –0°17 ′±1°
elevated*3–0 °10' ±1° –0°08 ′±1° —–0 °10' ±1°
Steering
axis
inclination
(reference
value) normal 5
°28 ′ 5°24 ′ 5°16 ′ 5°28 ′
elevated
*35 °18' 5 °16 ′ —5 °18'
Rear
suspension Type E-type multi-link
Spring type Coil spring
Stabilizer
Type Torsion bar
Diameter (mm {in})
4SD: 19 {0.75}
5HB: 18 {0.71}18 {0.71} 21 {0.83}
4SD: 19 {0.75}
5HB: 18 {0.71}
Shock absorber type Cylindrical,
double-acting
(Low-pressure gas charged) Cylindrical,
double-acting
(Low-pressure gas charged)/
(High-pressure
gas charged) Cylindrical,
double-acting
(High-pressure gas charged) Cylindrical,
double-acting
(Low-pressure gas charged)
Wheel
alignment
(Unloaded)*
1
Total toe-in (mm {in}) Tire: 2
±4 {0.08 ±0.16}, Rim inner: 1 ±3 {0.04 ±0.12}
(degree) 0 °11 ′±0°22 ′
Camber
angle*
2
normal –1 °13 ′±1° –1°06 ′±1° –1°03 ′±1° –1°13 ′±1°
elevated
*3–1 °05 ′±1° –0°58 ′±1° —–1 °05 ′±1°
Thrust angle (degree) 0 °±0°48 ′
REAR SUSPENSION
R–5
R
SUSPENSION CONTROL SYSTEMA6E741601013201Outline
•The self-leveling suspension is a system that adjusts the vehicle height according the amount of vehicle load.
This system will raise the rear of a vehicle, lowered due to a load placed on it, to the designated load level
* after
the vehicle has been driven a certain distance.
•The vehicle height adjustment is performed using a gas-pressurized pump function built into the rear shock
absorber.
•For the vehicle height to return to the designated load level, the vehicle must be driven approx. 5—6 km {3.1—
3.7 miles} in city driving conditions. (Distance will vary due to load and road conditions.)
•A load amount of approx. 140—300 kg {308—660 lb} at the rear axle will cause the vehicle height to be raised,
and any weight over that will prevent the vehicle from returning to the designated load level.
*: Designated load level is defined as the level at which the vehicle is with: a full fuel tank; engine coolant and oil at
specified levels; spare tire, jack and tools in designated positions; and four people, weighing 55 kg {121 lb} each,
riding in the vehicle.
Construction
.
REAR SUSPENSION
5
4
3
6
1
2
A6E74162001
1 Outlet check valve
2 Pump chamber
3 Low-pressure chamber4 High-pressure chamber
5Piston
6 Inlet check valve