2006 GREAT WALL HOVER ECU

Instroduction-6
9. Determine the necessity of using special maintenance tools and
special maintenance material according to the practical situation
of maintenance. Use them on the necessary position, and go on
with the maintenance according to proper procedures.
10. To replace the fuse, check to see whether the rated current of
new fuse is correct. Do not exceed the rated current of the fuse,
or do not use the fuse with low rated current.
11. When jacking up or supporting the car, lift or support the car on
proper position with care.
a. If only jacking up the car in the front part or rear part, choke up the
wheel to ensure the safety.
b. After the car is jacked up, use frame to support it. It is dangerous to
conduct maintenance on the car that is only jacked up with one
screw jack, even for the minor maintenance that can be finished
quickly.
12. Paying attention to the following matters to avoid the damage
of components:
a. If it is not absolutely necessary, do not open the housing of the
ECU and the computers (if the IC terminals are touched, the IC
may have electrostatic damage).
b. When removing the vacuum tube, pull the end of the tube instead of
the central part of the tube.
c. When pulling the wire terminal, pull the terminal itself instead of
the wire.
d. Take care to not make the electrical components fallen, such as the
sensor or relay.
If they fall to the hard ground, they must be replaced.
e. Never use the striking wrench to remove or install the electric
thermostat or thermostat sensor.
f. When checking the conducting state of the wire connector, insert
the multimeter with care, do not bend the terminal.
g. When using the vacuum meter, do not insert the soft tube onto large
connector. Use the stepped terminal. Once the soft tube is swelled
and tightened, there may be leakage.
error correct

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-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-29
In reverse-Gear position, the drive of transmission is sent to the clutch hub through the input shaft and rear clutch piston. In this
condition, the description of each function unit of transmission is shown as follows:
The clutch C3 is engaged and drive the reverse central gear to rotate in clockwise.
The engagement of B2 brake belt cause the rest of the planetary gear carrier, then make the long planetary gear rotates
around its shaft anticlockwise.
The long planetary gear drives the internal gear ring rotates anticlockwise .
Use the spline to connect the inner gear ring to the output shaft and drive the gear ring rotate anticlockwise or in reverse.
Control:
In stable status, to maintain the arrangement, the action of solenoid valve and valve is shown as follows:
A solenoid valve S1 or S2 is closed at least. (Refer to the part in section 3.3.11, related to condition when S1 and S2 is
closed.)
The line pressure reaches the internal surface and external surface of rear servo piston through the reverse lock valve
directly.
The line pressure urges the reverse-Gear loop oil pass through the manual-operated valve.
The reverse-Gear loop oil is circuited to clutch C3 through the manual-operated valve.
In the transmission whiteout HP pump shell, the reverse-Gear loop also can reaches the spring end of the primary
regulating valve to support the spring and push the line-pressure regulating valve.
The oil loop of execution line of all other clutches and brake belts is opened to leaking port.
Refer to Figure 5.2 and Table 5.3.
Table 5.3 The participating condition of each unit in reverse-Gear position
Gear-position
Reverse gear
Name of participated unit

Automatic transmission-47
4. Operating mode of transmission
TCU realizes the effective control for the transmission according to the accurate information acquired form the input data and
complete control for the output data. To ensure the input and output of TCU is actual and effective, TCU executes the data sense
command for hardware and software. For the failure information found in the following operating mode described in detail, TCU
will give the corresponding response.
Similarly, it exists the possibility that could not find out the failure cause. If encounter the condition, the operation for transmis
sion is determined difficultly.
Following condition will effect the operation of transmission, but will not appear the detection failure information.
a. Power supply failure
The transmission adopts the 3-Gear lame Home Mode (LHM) irrelevant to car speed.
If occur the intermittent power supply, then TCU will start form 4-Gear and is switched to the proper gear to meet the
requirement of current work. At this time, it will not monitor the power supply status.
b. The transmission fluid temperature is higher than 135
If found the transmission temperature is high:

The torque converter lock clutch will start in low speed and the car will have the vibration.

Some cars will have the condition that the mode indicator lamp is flash.
The reason for the condition may be the transmission fluid temperature is high or acquire the inaccurate single form the
temperature sensor. If occurs the temperature failure, it may find the high temperature operating condition.
c. Failure of ON/OFF solenoid valve
If one of the solenoid valves has the mechanical failure, TCU will not find the failure. At this time, the failure operation of
transmission will be determined according to the solenoid valve with failure. The characteristic of different solenoid valve failure
is listed in Table 6.1.2.
reverse pin
gear indication pin
Gear sensor(black)
Figure 6.1.1 Description for wire bundle pin

Figure 8.36 Primary regulating valve
Figure 8.37 Torque converter clutch regulating valve
s. Install the pump on the washer of transfer case of housing.
t . Make the O-ring is proper for the external diameter of pump.
u. Ensure the pump housing hole in main housing is clean and without dirt.
v. Ensure the plastic connector of solenoid valve 7 is installed on the correct position of main housing.
w. Install the pump and pump housing on the input shaft carefully and avoid the damage of gasket spring. Tighten the pump
housing spring. Refer to Figure 8.43 Figure 8.44.
x. Check whether the transmission end float is fixed in the clearance of part 9.2. Refer to It the end float without filling metal plate
is more than that in instruction, then the metal plate should be placed in surface of NO.4 bolt and input shaft bolt. Refer to
Figure 8.19. if the end float is less than 0.5mm or more than 0.8mm; then the transmission can not be installed correctly and
is beyond the specification partly.
Check the end floating by executing the following procedure:
Connect the disc indicator to the front end of the transmission; place the pointer on the end of input shaft.
Apply about 250N or 25kg force on the input shaft.
Zero the indicating pointer.
Install a small lever on rear of the front clutch cylinder.
The recorded measuring value is the end floating value or called as the clearance of No.4 bearing on torque converter
tube support.
After the completion of the process, adjust the front and rear brake belt according to the specification of details in part 8.4.

Brake-31
Antilock Braking System (ABS)
Cautions
1. It must not remove or install the electric elements and wire bunch plug when the ignition switch is in ON to avoid
the damage of ECU. It should turn off the ignition switch if needs disassembly.
2. Pay attention to do not knock or impact the ABS ECU during the maintenance and repair, for it will damage the
ABS ECU easily.
3. The wheel speed sensor and hydraulic unit (integrated with ECU) of BOSCH ABS8.0 can not be repaired, it should
be replaced in integral if damaged.
4. After the brake system is maintained, the brake pedal maybe soft. Discharge the air according to the normal brake
system.
5. It must use the brake fluid from original manufacturer; the brake fluid of different number cannot be used in mixed,
otherwise it will cause the failure of brake system. Select the tyre of original type as most as possible
Repair of Antilock Braking System (ABS)
1. It should process the failure diagnosis for the brake system before process the ABS failure diagnosis. It can
diagnose out the failure rapidly by using Table 1. In Table 1, the small number means the failure which occurs most
possibly. Check each element according to the sequence and maintain or replace it if necessary.
2. Check the following elements for normal operation before the diagnosis:
Brake fluid level and brake fluid quality
Pressure of tyre, size of tyre, shape and depth of tyre figure
Other brake component
These components will affect the brake effect of the ABS. Check the system sensor, connecting wire and connector for correct
installation, arrangement and connection. Ensure the completeness of fuse, repair or replace it if necessary.
3. Process the analysis and diagnosis according to the ABS advanced by owner. Use the diagnosis instrument (Annex
1) for final check and confirmation. It must process the run inspection after the competition of all ABS maintenance.
The test condition is shown as follows:
a. Confirm the tyre complies with the requirement, the tyre pressure is normal.
b. The brake system (including brake light ) is normal
c. The brake system is without leakage.
d. The position and installation of wheel speed sensor is correct.
e. All fuses are normal.
4. test method:
Run for 1 min at least when the vehicle speed is beyond 40Km/h, process a proper brake. Then read out the failure code to
ensure the ABS is without failure code.

Steering-5
Technical requirements
1.The fastening torque of the mounting bolts of the integral power
steering gear assembly is
2.The fastening torque of the connecting bolts of the steering drive sub-
assembly and the integral power steering gear assembly is
3. The fastening torque of the connecting bolts of the steering drive
assembly and the left horizontal beam of the frame is
4. The fastening torque of the mounting bolts of the power steering
pump is 40N.m.
5. The tension force of multi-wedge belt 4PK1100 is 4PK1100.
6. Centering fastening of the handwheel: steer the front wheel to the
right front and remove the handwheel without changing the position
of the steering stem, install the handwheel aligning the center, the
radials of the handwheel should be at the left & right centering state;
the symbol of “the Great Wall” on the steering wheel shall be in
driver’s straight view position, secure the nut firmly with the
fastening torque of
7. Inspection of free clearance of the handwheel
Steer the car in a straight direction and stop the engine, apply a 5N force to
the handwheel along the circumference, left turn the handwheel and stop
the turning when the resistance is increasingly felt with each turn; then right
turn the handwheel and stop the turning when the resistance is increasingly
felt with each turn; the angle rotated along the circumference is the free
clearance of the handwheel, whose standard value shall be below 20
, and
the angle from the center to the right shall not be more than 10