2006 GREAT WALL HOVER automatic transmission fluid

Automatic transmission-37
power transmission Automatic 3rd-Gear and manual 3rd-Gear
In automatic and manual 3rd-Gear, the drive of transmission reaches the front cylinder through the input shaft. In this condition,
the operating principle of the transmission is shown as follows:
The engagement of clutch C2 drives the front sun gear
The engagement of clutch C1 drives the planetary gear carrier
The forward central gear and planetary gear carrier rotate in the same speed clockwise. So, there is not relative motion
between the forward central gear and planetary gear.
The gear ring and output shaft rotate in the speed of output shaft, and makes the moves forwardly.
The engagement of clutch C4 is through the 3-4 one-way clutch (OWC) and make the engine to provide the brake force
in overspeed.
Control:
In stable status, the status of solenoid valve and valve is shown as follows:
The solenoid valve S1 is powered off; Solenoid valve S2 is powered off
When the solenoid valve S1 and S2 is powered off, 2-3 and 3-4 shift valve are kept in 3rd-Gear position through the line
pressure 500.
1-2 Gear shifting valve is kept in 3rd-Gear position by the oil pressure of S1 and S2.
The (line pressure)oil form the 1-2 Gear shifting valve flows into the brake belt combination regulating valve directly and
flows into the 2-3 Gear shifting valve.
The brake belt combination regulating valve provides the 2nd-Gear oil (controlled by the product of line pressure and valve)
to the brake belt feed loop(BAF).
The brake belt feed loop directly provides the oil to:
External combination part of front servo
When the transmission is shifted to 1st-Gear, the 1-2 Gear shifting valve provides the oil drainage port.
When the transmission is in 4th –Gear position, it will use the 3-4 Gear shifting valve.
The 2nd-Gear oil of 2-3 Gear shifting valve flows into the 3rd-gear loop directly .
The 3rd-Gear oil from the 2-3 Gear shifting valve flows into the clutch combination regulating valve and sequence valve of
4-3 Gear directly.
The clutch combination regulating valve provides the oil of clutch attachment feed loop (controlled by the product of line
pressure of 500 and valve ratio) (CAF).
CAF directly provides the oil to :
clutch C1
Sequence valve of 4-3 Gear
In 4-3 Gear shifting valve, the CAF oil is changed to the release fluid of B1 (B1R-F), it cause the closing of brake belt 1
through the 3-4 Gear shifting valve to spring bottom of 4-3 gear sequence valve and release side of front servo.
The drive force (line pressure ) is sent to the clutch C4 through the 3-4 Gear shifting valve to engage the clutch C4 .
Refer to Figure 5.6 and Table 5.7.
Table 5.7
Table of participating condition of each unit in automatic and manual 3rd –Gear
Clutch
Name of participation unit
Automatic and manual
3
rd –Gear

Automatic transmission-45
Diagnosis and test
Test system
1. Recommended test equipment and program
The test equipment and control unit for design will be used for the test of all vehicles. The parts for transmission test includes:
Tester for service after sales
Special vehicle for test
2. Tester for service after sales
After the special programming, the tester equipped with special car test software can be used to test the specified system and unit.
The program allows the normal communication between the transmission control units (TCUs) .
The computer needs the required information from the customer and select the necessary data through the manual. For example:
view the code, clear the error code and make the real-time operation. For detailed operating instruction refer to user’s manual.
The equipment can be used by the trained specialized persons, such as technician, machinist to test the electronic and loop
problem related to transmission. The testable information includes: the engine speed, rode (shaft speed), transmission fluid
temperature, position of throttle position, status of solenoid valve and gear and position of operating lever. Additionally, it can be
used to detect the current and stored problem.
3. Description of TCU pin
The description of TCU pin code had been listed in Table 6.1.1
For description of wire bunch refer to Figure 6.1.1
Pin No. Function Type 2WD description
A14 Public grounding GND
● Negative pole of TCU supply, connected to negative pole of
battery.
A13 Nonuse
－－
○ －－－－－
A12 M ode indicator la mp
Snowland mode OP
● Indicate that select the “Snowland M ode” operating method.
A11 Parking-Gear indicator lamp O P
● T he drive instrum ent panel indicator la mp indicates tha t is in
the “Parking G ear”
A10 Reverse-Gear indicator lamp OP
● T he drive instrum ent panel indicator la mp indicates tha t is in
“ Revers e G ear”
A9 N-G ear indicator lamp O P
● T he drive instrum ent panel indicator la mp indicates tha t is in
“Idle N Gear”
A8 Nonuse －－ ○ －－－－－
A7 Nonuse －－ ○ －－－－－
A6 M ode indicator la mp
dynamic mode OP
● Indicate that select the “ dyna m ic mode” operating method.
A5 Nonuse ―― ○ －－－――
A4 Nonuse ―― ○ －－－－－
A3 Nonuse ―― ○ －－－－－
A2 Mode switch IP
● The switch is used to select the “economic mode”, “dynamic
m ode” and “ snowla nd mode”. T he voltage is varia ble in
range of 0 V－2V .
A1 Nonuse ―― ○ －－－－－
A30 Power supply PWR
● Power supply for TCU; is the main power source of drive
unit and solenoid valve.
A29 Nonuse ―― ○ －－－－－
A28 1st-G ear indicator lamp
/1st-G ear position﹡ OP
● Drive the instrument panel indicator lamp indication, indicate
that the gear-position is in “1st-G ear”
A27 2nd-G ear indicator lamp
/2nd-G ear position OP
● Drive the instrument panel indicator lamp indication, indicate
that the gear-position is in “2nd-G ear”
A26 3rd-G ear indicator lamp
/3rd-Gear position﹡ OP
● Drive the instrument panel indicator lamp indication, indicate
that the gear-position is in “3rd-Gear”
A25 Automatic gear indicator
lamp /4th –Gear position OP
● Drive the instrument panel indicator lamp indication, indicate
that the gear-position is in “automatic-Gear”

Automatic transmission-46
Pin
No. Type 2W D Description
A24 CAN (-ve) I/O ○ CAN hidden communication end
A23 CAN (+ve) I/O ○ CAN exposed communication end
A22 K line communication
connection I/O ● Diagnosis information and car code
A21 Nonuse ―― ○ －－－－－
A20 Nonuse ―― ○ －－－－－
A19 Shaft speed sensor
signal IP ○ The sensor sends the shaft speed signal to T CU
A18 Nonuse ―― ○ －－－－－
A17 Nonuse ―― ○ －－－－－
A16 Nonuse ―― ○ －－－－－
A15 Nonuse ―― ○ －－－－－
B6 Gear-position IP ● T h e sw itch ha s th e variab le-vo ltage ; in dicate the
gear-position steering colum n selected (PRND321). The
vo ltage is variab le in the ran ge o f 0 V --5 V .
B5 transm ission fluid
temperature IP ● The sensor indicates the transmission fluid temperature.
High R=Low temperature
Low R= High temperature
The voltage is variable in the range of 0V to 5V
B 4 so leno id va lve 4 O P ● N /O FF no rm al-op ened so leno id valve , co m b ined w ith the
O N /O FF w itch o f so len oid valve 3; en sure the sh ifting
quality and sequence
B 3 so leno id va lve 1 O P ● ON/OFF normal-opened solenoid valve; combined with
o the r so leno id va lve; u sed to determ ine the selected
gear-position.
B2 Nonuse ―― ○ －－－－－
B1 R e tu rn so len oid va lve
5 IP ● Using for grounding of VPS and current of circuit can be
detected, then process the feedback control for the VPS.
B14 Gear-position －
grounding GND ● PRND321 Gear-position switch grounding
B13 transm ission fluid
temperature －
grounding GND ● Connected to grounding pin of temperature sensor.
B12 solenoid valve 6 OP ● ON/OFF normal-opened solenoid valve, determine the
high or low of line pressure
B11 solenoid valve 2 OP ● O N /O FF norm al-o pened so leno id va lve, co m bined w ith
o the r so leno id valves; u sed to d eterm ine the selected
gear-position.
B10 solenoid valve 3 OP ● O N /O FF norm al-o pened so leno id va lve, co m bined w ith
the O N /O FF sw itch of solenoid valve 4; ensure the
shifting quality and sequence
B 9 so leno id va lve 7 O P ● ON/OFF normal-opened solenoid valve, hydraulic torque
converter locking; increase the efficiency of medium
speed run.
B8 Nonuse ―― ○ －－－－－
B 7 so leno id va lve 5 (+ ve) O P ● It is the so leno id va lve w hich can ch an ge th e p ressu re
d urin g the sh iftin g a nd on /o ff o f so leno id valve .
●= connected line ○= unconnected line ＊=only
OP= output IP=input I/O=input/output
GND=grounding REF=reference PWR=power
Table 6.1.1 Description of TCU pin

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

Automatic transmission-48
s oleno id
valve Condition Transmission operation
1 Opened
always 1st-Gear replaces 2nd-Gear; 4th-Gear replaces 3rd-Gear. It causes the car form the G ear shift of 1
→1→4→4 when accelerate form static. The transmission stay longer time in Gear; worse 1→4
shift feeling.
Closed always 2nd-Gear replaces 1st-Gear; 3rd-Gear replaces 4th-Gear. It causes the car form the G ear shift of 2
→2→3→3 when accelerate form static. It is said that starts form 2nd-Gear.
2 Closed always 4th-Gear replaces 1st-Gear; 3rd-Gear replaces 2nd-Gear. It causes the car form the G ear shift of 2
→2→3→3 when accelerate form static. That is saying that start form 4th-Gear.
Opened
always 2nd-Gear replaces 3rd-Gear; 1st-Gear replace 4th-Gear.
It cause the car is shifted form 1st-Gear to 2nd-Gear, then from 2nd-G ear to Gear when accelerate
form static. It will feel the transmission is in free gear position after 2→1 Gear shift.
1&2 Opened
always Can not realize the reverse gear; only has 1st-Gear operation.
3 Closed always Following shifts are bad. (2→3 is worst ):1→3, 1→4, 2→3, 2→4, 4→2, 4→1
Opened
always Following gear shifts are worse: 3→4, 4→3, 3→2。
It may cause the gear slide when the hydraulic torque converter is locked.
4 Closed always Following gear shifts are worse:
1→2, 1→3, 1→4, 2→3, 2→4, 3→1, 3→2, (including manual) 3→4, 4→1, 4→3
Opened
always Following gear shifts are worse: (1→2 is worst) 2→4, 3→2 It may cause the gear slide when
the hydraulic torque converter is locked.
6 Closed always The line pressure is high always.
Opened
always The line pressure is low always. So it cause the slide between gears. The clutch C1 and brake belt
B1 will be burned.
7 Closed always The hydraulic torque converter is without lock.
Opened
always The hydraulic torque converter is locked in 3rd-Gear and 4th-Gear. It cause the car generates the
vibration in low-speed status.
Table 6.1.2 Operation of transmission when ON/OFF solenoid valve is faulty
Mechanical detection
1.Inspection of transmission on car
It should process the following detections before disassemble the transmission:
process the on-road drive test to determine the failure cause .(according to requirement)
Detect the standard of transmission fluid. (refer to 7.2.1)
Ensure the transmission fluid in not overheated. (Normal color and smell)
Detect the failure information.
Check the battery terminal and grounding for corrosion or loose.
The engine speed is within the specified value in manual.
Check the cooling system for normal operation.
All power supply and plug wires is tight and not loose.
Check the transmission fluid, ensure the oil pan is without other martial material or pollutant.
2. Oil leakage detection
It should wash the polluted part of the transmission before select the oil leakage part, then drive the car.
When detect the leakage part of the rear servo system, it should lift the car by lifter firstly, then switch the gear to reverse
gear within 10s.
When detect the leakage part of front servo system, it should lift the car by lifter firstly, then switch the gear to gear-2
(winter mode).
The time switched to 2nd-Gear should be no more than 10s to avoid the oil in the torque converter is overheated.
3. FAQ table

Automatic transmission-49
The distribution of FAQ table is shown as follows:
Table 6.2.1 Drive failure Table 6.2.3 Shift quality failure
Table 6.2.2 Shift mode failure Table 6.2.4 Disassembly failure
failure Possible reason Corresponding measure
“D”-Gear operation
has not drive The automatic transmission fluid is insufficient.
The oil-entering of C1/C2 piston is blocked.
The “Z” is assembled incorrectly.
The primary regulating valve plug is opened.
The overspeed shaft or input shaft sealing ring is
failure.
3→4, 1→2 single-way clut ch is installed in revers e or
failure. Check the liquid level. Fill it up if necessary.
Check and wash the C1/C2 oil inlet device.
Reinstall the “Z” connection.
Remove, wash and reinstall the primary
regulating valve.
Check and replace it if necessary.
Check and replace it if necessary.
The reverse shifting
operation is without
drive.
The manual 1
st-Gear
has not engine
brake.
The engine brake is
normal in manual
1
st-Gear. The input shaft oil seal ring is damaged.
The rear brake belt or servo system is faulty.
C3, C3 wheel shaft or C1/C2 cylinder are out of work. Check and replace it if necessary.
Test the servo system or replace the rear brake
belt according to the requirement.
Test the failure C3, C3 wheel axle or C1/C2
cylinder.
Repair it in time if necessary.
“D” –Gear and reverse
–Gear operation is
without drive. The primary regulating valve is blocked.
The pump gear is damaged.
Take out the output shaft clasp. Det ect and clean the primary regulating valve.
Check and replace the pump gear if necessary.
Check and repair it if necessary.
Only can 2→3 shifting
(can not realize the
4
th-Gear and 1st-Gear) S1 is closed always. Test the S1. Repair or replace it if necessary.
Test the failure of S1 12V power supply
voltage or wire bundle.
Only can 1→4 shifting
1→3→4 shifting (1
→2 shifting delay). S1 is opened always Test the S1. Repair or replace it if necessary.
Test the failure of S1 12V power supply
voltage or wire bundle.
Only can 4→3 shifting S2 is closed always.
Test the S2. Repair or replace it if necessary.
Test the failure of circuit break or wire bundle.
1→2→neutral position
shifting (1st-Gear
transition) S2 is opened always Test the S2. Repair or replace it if necessary.
Test the failure of circuit break or wire bundle.
Only can 1→3 shifting B1 is out of work
The brake belt is loose.
The front servo piston or oil s eal is out of work.
S1/S2 ball spool is reinstalled in wrong place. Test and adjust it according to the requirement.
Test and maintain it according to the
requirement. Test and replace or reinstall it according
to the requirement.

Only can 1→3→4
shifting The small O-ring of front s ervo piston is invalid or
lost.
2→3 Gear position shifting valve is blocked. Det ect the O-ring. Process the replacement or
reinstallation if necessary. Detect the 2→3
Gear shifting valve; Process the maintenance
or replacement according to the requirement.
Only can 1→2→1
shifting C1 is invalid or 3rd-Gear and 4th-Gear is loose. (give
to 1st-Gear in 3rd-gear; give to 2nd-Gear in 4th-Gear) Det ect the clutch C1. Repair or replace it if
necessary.
Can not realize the
man ual 4→3, 3→2, 2
→1 Overspeed clutch /ball spool has displacement.
C4 is invalid. Detect the ball spool. Process the replacement
or reinstallation according to the requirement.
Det ect the C4. Repair C4 or r eplace the C4
wave pan according to the necessary.

Adjustment
Hydraulic system
Following parts is the detailed description for self-detection procedure pointed to the condition occurred in chapter
6. including the condition indicated the failure, to point the problem existed in the hydraulic system.
It should select the proper procedure from the following primary detection when adjust the transmission.
Detection process of transmission fluid
Detect the manual linkage adjusting system(refer to factory manual of car)
Detect the engine idle speed
Anchoring test (beyond the scope of the maintenance manual)
On-road test (beyond the scope of the maintenance manual)
Detection procedure of transmission fluid level
1. General

The process is used to detect the level of vehicle transmission fluid. It will cause the failure or delay of transmission shifting if
the level is low than required value and the vehicle does not reach the drive temperature.
Firstly, process the transmission diagnosis information detection for vehicle (refer to chapter 6). If found the failure of sensor,
then it maybe caused by transmission fluid level is less than specified value.
It should detect whether has the abnormal delay and Gear-position condition when select the forward or reverse-gear by driving
the vehicle. One feature of oil level less than normal value is that the vehicle has the gear-position delay and lack condition when
the vehicle is in steering. The previous problem will occur when the transmission fluid temperature is low.
When the oil temperature is medium and vehicle speed failure is recorded, the gear-position lose condition
will not occurs any longer, it means that needs to fill the transmission with the transmission fluid.
2. Detection of transmission fluid level

When fill up or replace the transmission fluid, it must use the Castrol TQ95 automatic transmission fluid (ATF) or other
permissive oil. It will damage the performance and service life of transmission if use the unpermissive transmission fluid.
Please ensure the transmission fluid level is correct. The transmission also can be damaged if the transmission fluid level is
incorrect.
The setting procedure of transmission fluid level is shown as follows:
Caution:
When the transmission is in operating temperature, the hot transmission fluid may flow out form the
housing if remove the filling plug.
a. If the vehicle is in operating temperature, allow two hours time for cooling before add the transmission fluid, but
it must not more than 4 hours (this will make the transmission locate in the correct temperature range). When the
temperature is overheating, the transmission fluid level will higher than the plug port. Removal of plug will cause
the transmission fluid flows out from the oil filling port, then cause the low level of transmission fluid.
b. The gear-position of transmission is in parking-Gear (P-Gear), shut off the engine.
c. Lifting the vehicle (or parking above the trench).
d. Clean the around of plug when remove it. Then remove and clean the plug and check the O-ring for damage. Install
the oil filling pump in the oil filling hole.
e. Lower the vehicle; the oil filling pump will be connected to the vehicle at this time. Fill the transmission with the
oil partially. Then start the vehicle in P-Gear to rotate the engine in idle speed. Step down the foot brake, pull the
shifting lever in each gear-position in circulation and add the transmission fluid until the action of each gear-
position can be sensed.
f. Shut down the engine; lift the vehicle; ensure the vehicle is always in horizontal.
g. Remove the filling plug 3 minutes after the engine is shut off, but must not be no more than1 hour. At this time, the
correct level position should be in the bottom of oil filling hole. If does not reach the liquid level position, then fill
with few transmission fluid to make it reach the correct level.
h. Replace the transmission; clean the residual transmission fluid on the transmission and
vehicle.
i. Tighten the transmission plug to the specified torque of 30
35Nm.

3. Oil filling of service after sales
Set the liquid level position correctly; the procedure is shown as follows:
a. Shut down the engine; place the gear-position in the P-Gear.
b . Lift the vehicle (or place it above the trench).
c. Clean the around of plug before remove it. Remove the oil plug and check the O-ring for damage, finally connect the oil filling
pump to the oil filling hole.
d. Lower the vehicle and oil filling pump to the ground; fill with the transmission fluid partially. The general oil filling amount
is shown as follows:
If in the status of transmission hydraulic torque converter is empty: 8.0 L
If in the status of transmission hydraulic torque converter is full: 3.8 L
e. When start the vehicle in P-Gear, rotate the engine in idle speed. Step down the foot brake, pull the shifting lever in each gear-
position in circulation and add the transmission fluid until the action of each gear-position can be sensed.
f. Then fill with 0.5L transmission fluid (ATF) additionally.
g. Shut off the engine, lift the vehicle; take off the pump and replace the plug. Ensure the plug is tightened according to the
specification.
h. Then pull the vehicle throttle position for slight opening to make the vehicle runs for 3.5
4.5km; the rotary speed of engine
is no more than 2500r/min; then the transmission fluid temperature will in the scope of 50
60.
i. The engine is in idle-speed; pull the hand brake to make the shifting lever circuits in each gear-position horizontal status.
k. Remove the filling plug 3 minutes after the engine is shut off, but must be no more than1 hour. At this time, the correct
level position should be in the bottom of oil filling hole. If does not reach the liquid level position, then fill with few
transmission fluid (ATF) to meet the requirement.
l. Reinsert the transmission fluid plug, remove the residual transmission fluid around the vehicle and transmission; tighten the
plug to the specified torque.
4. Replace the ATF
Please notice that the color of TQ95 automatic transmission oil will be faded in the normal operation of transmission; it will be
turn into the deep brown or even in black. It will not affect the performance of ATF. It means that the fading of transmission
fluid not always means to replace the transmission fluid.
If the transmission temperature is raised, the ATF will be burnt. In this condition, ATF will change into black and with special
sulfur smell. The smell of the ATF means the oil is burnt.
If the ATF is burnt, it will cause the damage of transmission (the clutch assembly is damaged at least).At this time, it should
disassembly the transmission and process the necessary detection.
Electronic calibration
1. Idle-speed calibration
The idle-speed calibration is introduced in detail in the vehicle factory manual.
2 Calibration of position of throttle position

If the throttle position information stored in TCU is lost or not in application scope. It can be reestablished according to the
following program as the diagnosis error information.
a. Check whether the engine idle speed is in required range.
b. In the status of shutting off of air-condition, make the engine is in “D” –Gear for 60s,then the reference point with opening
degree of 0
of throttle position is reset in TCU.
Shut off the engine; switch on the ignition device, step the accelerator pedal to bottom for 60s, then the reference point with opening
degree of 100
of throttle position is reset in TCU.
3. Clear of throttle position

The clear process set by learning throttle position is necessary for M88 transmission TCU.
4. Car code

For M88 transmission, the car code is unnecessary.