2006 GREAT WALL HOVER automatic transmission

Automatic transmission-7
Indicator lamp
Figure 2.2
control system
General
The transmission has two sets of control system, a electric control system and a hydraulic control system. The electric control
system monitors the vehicle parameter and adjusts the transmission performance; the hydraulic control system executes the
command of electric control system.
Electric control system
The electric control system consists of the sensor, TCU and 7 solenoid valves. TCU read in the data and make the output under the
control of software based on the value stored in Read Only Memory (ROM).
TCU controls the hydraulic control system and the control is realized through the valve and pump assembly. The system includes
7 solenoid valves, in which 6 valves are used to control the line pressure, operate the shift valve and hydraulic torque converter lock
clutch and switch on and off two regulating valves (Two regulating valves control the shift feel). The seventh solenoid valve is the
pressure regulating solenoid valve (VPS) which controls the shift feel with other three regulating valves. Figure 3.1 is the typical TCU
control system plan.
The figure includes all elements of electric control system involved in the section.
throttle position
open sensor
Engine speed
vehicle speed
Transmission
fluid temperature
mode selection
(instrument panel
/console )
Gear sensor
Forced step-
decreasingK line
shifting
logic
shifting
sensing
line
pressurehydraulic
control
system
Solenoid valve 1
Solenoid valve 2
Solenoid valve 3
Solenoid valve 4
Solenoid valve 5
Solenoid valve 6
Solenoid valve 7
pressure regulating
solenoid valve
Mode indicator lamp
Gear indicator lamp
set and other
necessary equipment
indication

Automatic transmission-8

Automatic transmission-9
Table 3.1 Feature parameter of temperature /resistance
-2013,638
5,177
2,278
177
7517,287
6,616
2,723
196
85


Figure 3.2 Pin number of temperature /resistance
Pin No. Wire color Connected solenoid valve
1 Red solenoid valve 1
2 Blue solenoid valve 2
3 yellow solenoid valve 3
4 orange solenoid valve 4
5 green solenoid valve 5
6 violet solenoid valve 6
7 brown solenoid valve 7
8 green solenoid valve 5
9 white temperature sensor
10 white temperature sensor
ohm
Temperature
Centigrade degree

Automatic transmission-10
Figure 3.3 Schematic diagram of temperature sensor position and solenoid valve wiring
2.Throttle position sensor
Figure 3.4 gear sensor
solenoid valve 4 (orange )
ground wire (2)
solenoid valve 7 power supply connectorolenoid valve 6 (violet ) ground wiretemperature sensor solenoid valve (red ) ground wire
solenoid
valve (green )
solenoid valve (yellow )
solenoid valve (blue ) ground wire
ground wire
ground wire

Automatic transmission-11
Diagnosis input
solenoid valve
1and 2 S1 and S2 is the normal open solenoid valve, which is used to set the gear-position with other switch
solenoid valve. It determines the static gear-position by operating the gear shift valve. Refer to Table 3.5,
S1 and S2 also send the pressure single to allow or prohibit the engagement with rear brake belt.
solenoid valve
3and 4 S3 and S4 are the normal-opened solenoid valve which is used to control the shifting quality and sequence in
combination. S3 control the open or close of the clutch. S4 is used to control the on and off of the front brake
belt regulating valve.
solenoid valve 5 S5 is the variable pressure solenoid valve which can release the pressure of gear-position shifting. It provides
the pressure signal to the clutch and brake belt regulator and controls the shifting pressure. S5 also provides
the pressure single to the torque converter clutch regulating valve.
solenoid valve 6 S6 is the normal-opened solenoid valve, which is used to the set the H/L level of pipeline pressure. The
pipeline pressure is high when the solenoid valve is closed.
solenoid valve 7 S7 is the normal-opened solenoid valve which is used to control the engagement status of torque converter
licking clutch. It makes the clutch to generate the action when the S7 is in opened status.
Table 3.4 Status and function of solenoid valve

Gear-position S1 S2
1st-Gear On On
2nd-Gear Off On
3rd-Gear Off Off
4th-Gear On Off
R-Gear One of them is in On position
at least.
N-Gear Off Off
P-Gear Off Off
Table 3.5 Logic status of solenoid valve in static gear-position

Automatic transmission-12

Shifting Initial shifting status Current variation of S5 Finished shifting status
1－2 S1 Off
S4 On 950mA－650mA
S4 Off

1－3 S1 Off
S2 Off
S3 On
S4 On 900mA－400mA
S3 Off
S4 Off
1－4 S2 Off
S3 On
S4 On 850mA－750mA
S3 Off
S4 Off
2－3 S2 Off
S3 On
S4 On 700mA－200mA
S3 Off
S4 Off
3－4 S1 On
S4 On 950mA－550mA
S4 Off

4－3 S4 On 950mA－700mA S1 Off
S4 Off
4－2 S3 On 800mA－500mA S1 Off
S2 On
S3 Off
4－1 S3 On
S4 On 1000mA－600mA
S2 On
S3 Off
S4 Off
3－2 S2 On
S4 On 550mA－400mA @ 20kph
800mA－600mA@60kph
1000mA－800mA@100kph S4 Off
3－1 S3 On
S4 On 1000mA－750mA S1 On
S2 On
S3 Off
S4 Off
2－1 S4 On 1000mA－500mA S1 On
S4 Off

Torque converter clutch
On
Off S7 On 1000mA－500mA
900mA－600mA S7 Off

Table 3.6 Operation of solenoid valve during shifting period

Automatic transmission-13
Symbol of solenoid valve (On/off solenoid valve)
Figure 3.5 Normal-opened type
1.Variable pressure regulating valve regulating system
The shifting pressure of abrasion unit is controlled by the variable pressure regulating valve.
The line pressure is independent of the shifting pressure and determined by the thro
position, shifting status and engine speed.
S5 is a proportional or variable pressure regulating valve which provides the pressure signal control shifting pressure for
the clutch and brake belt regulating valve.
In automatic shifting period, it process the integral times enlarging and contracting
regulation for the clutch regulating valve, brake belt regulating valve, torque converter regulating valve and VPS.
The hydraulic pressure generated by variable pressure regulating valve is in inverse ratio with current. During the shifting, TCU
will increase or decrease the current of solenoid valve according to the program. The current is variable in the range of 200mA
to 1000mA. The increasing of the current will decrease the S5 output pressure; the decreasing of current will increase the output
pressure of S5.
Lin 500 pressure (about 440 to 560kPa) is the reference pressure of VPS, meanwhile, the VPS output pressure equals to the
pressure on line 500 always.
When the VPS is in waiting status, it means there is not the generation of shifting action. VPS current is 200mA. At this time,
it gives the maximum output pressure.
In stable status, the brake belt and clutch regulating solenoid valve is in closed status. In this condition, the pressure of line 500
is applied on the piston. For the line 500 pressure is more than S5 pressure always, so it pushed the oil in S5 to the place
between the regulating valve and piston. At this time, oil pressure applied on the friction unit equals to the product of pressure
on line 500 and magnification factor.
During the starting of shifting, the used on/off solenoid valve is in opened status which cut off the oil loop supply from line 500
to piston.
At the same time, VPS pressure is decreased to starting pressure valve, pressure set by regulating valve and pressure setting
value required by execution of VPS by pushing the piston from the valve. The shifting is finished through the on/off solenoid
valve, VPS returns to the waiting status
Pointed to each gear-position, the system can make the brake belt; clutch or both realize
the electronic control.
Mode indicator lamp: the mode indicator lamp can be used to indicate the current selected and whether the overpeed status
exists. The mode indicator lamp is located in instrument panel generally. (Refer to Part 2.3)

Automatic transmission-14
The main box includes:
z BIR blow-off valve
1. Valve
Figure 3.7 shows the valve unit in the view of transmission fluid tank. Figure 3.8 illustrates the pump cover.
2. Manual-operated valve
The manual-operated valve (refer to Figure 3.9) is connected to the car gear selection mechanism. It controls the transmission
fluid flow to the forward or reverse loop. Except in manual 1st-Gear position, the function of manual-operated valve is same
in all forward gear. In manual 1st-Gear, the transmission fluid will enter into the shift valve 1
2 to make the rear brake belt
and C4 overspeed gear clutch is engaged respectively. The hydraulic control system is located in the valve, pump and main box.
The valve includes the following types:
zManual-operated valve
z Three shift valves
zsequence valve
z electromagnetic pressure control valve
zline pressure control valve
zclutch connection regulating valve
zbrake belt connection regulating valve
zsolenoid valve 1 to solenoid valve 6
zreverse lock valve
The pump includes the following types:
zprimary regulating valve (control line pressure)
ztorque converter clutch regulating valve
ztorque converter clutch control valve
z
solenoid valve 7 Hydraulic control system