oil pressure JAGUAR XJ 1994 2.G ZF Automatic Transmission Manual

ZF Automatic Transmissions Service Manual
Valve
Reverse Gear
Clutches 'B','D' and 'E' are
engaged.
As the front planet gear carrier of epicyclic gear set
'1' is
locked, the direction of output shaft rotation is reversed.
Epicyclic gear set
'2' also rotates as a solid block.
Summary of function
J4L-698
Fig. 1
Pressure regulating
1-2 shift valve
2
-3 shift valve
1.1.4
This housing contains the output shaft and speed governor and the parking lock mechanism. The governor comprises
two spring loaded valves, a spindle and a weight; the governor is influenced by centrifugal and hydraulic forces and
supplies a varying hydraulic pressure.
The parking lock pawl operates on
a toothed wheel attached to the output shaft speed governor; the mechanism is
operated from the selector (position 'I") by actuator rod.
Transmission Output Shaft Extension Housing
Varies line pressure as required
Line pressure to
C & C1 clutch valves and dampers
Line pressure to
C1 clutch (2nd); line pressure to B clutch (3rd)
1.1.5 Transmission Control Unit
The hydraulic control unit comprising a series of valve blocks housing the manual (selector) valve, control pistons and
pressure valves, is attached to the underside of the transmission housing; the unit controls the operation of the gear
train clutches and directs oil pressure to the appropriate system components (refer to illustrations, pages 5 to 7 ) to
operate the transmission. The valve blocks are connected to a main gallery plate.
Line pressure from the hydraulic pump is supplied initially to the pressure regulating valve, manual valve, governor,
3
-4 shift valve, 'E' clutch and damper, throttle valve, modulator valve and torque converter pressure (and reversing)
valve. The function of each of the valves in the control unit and the governor valve is summarised in the table below.
2nd gear inhibit
3
-4 shift valve
Throttle valve
Modulator
Converter
& Reversing
Reverse inhibit
F Clutch inhibit
Converter clutch hysteresis
Converter clutch lock
-up
Converter clutch damper
Clutch valves
& Dampers
Governor Line pressure
to 2
-3 shift valve
Line pressure to
E clutch (3rd); line pressure to F clutch (4th)
Throttle pressure to modulator and shift valves
Modulated throttle pressure fed to clutch dampers and valves
Line pressure to lock
-up clutch; lubrication oil to cooler
Line pressure to B
& D clutches
Governor pressure to 3
-4 shift valve inhibited in reverse
Governor pressure to converter clutch hysteresis valve
Line pressure to converter pressure valve
(D4 selected)
Aids quality of converter clutch application
Aids quality of clutch application relevant to modulator
& line pressures
Varies pressure in accordance with road speed
Issue 1 August 1994 4

1.1.6 Gearshift Selection
Gearshift selection is by movement of the shift lever which through a selector cable causes repositioning ofthe manual
(selector) valve to direct oil pressure to the required shift valve. The automatic shift points are determined by acceler- ator position and road speed: throttle movement moves a cam on the throttle valve, directing oil pressure to the shift
valves and modulator valve, road speed modulates hydraulic pressure through a centrifugal governor driven by the
transmission output shaft. Operation
of the hydraulic control system is shown diagrammatically in the circuit dia
-
grams on the following pages.
I I
I
I
2 -3- I
I I
I
I
- I
I I 1 4 -5 - - -
+ ! + I I 'I 10 I I
I
I 1
1, 1-Y I
I I
I
I
1. Engine 8. Pump regulator valve 2. Torque converter 9. Damper
3. Pump 10. Governor valve 4. Clutch & gears 11. Shift valve 5. Governor 12. Kickdown cable &throttle cam 6. Shift 13. Throttle / modulator valves 7. Solenoid valve 14. Transmission housing
Fig.
1 Schematic Diagram of Hydraulic Control
I. 1.7 Throttle Valve Mechanism (kick-down)
The throttlevalve or 'kick-down' mechanism comprises a cable connected between throttle body pedal and the throttle
valve cam/ quadrant located on the selector valve shaft; the cam operates the throttle valve housed within the throttle
valve block. The travel of the valve is proportional to throttle positions and alters shift speeds and pressures during
gearshifts to take account of throttle position. The mechanism also provides for immediate selection of a lower
ratio (eg when overtaking) by depressing the accelerator beyond the normal full
-throttle position. 'Kick-down' is oper- ated by movement of the throttle cable into the 'kick-down' position causing full movement of the throttle valve and
directing oil flow to the shift valves.
1.1.8 Starter Inhibit Switch
The starter inhibit switch prevents the starter motor from being operated when the shift lever is not in position 'P' - Park or position 'N'- Neutral. The switch is located in the gear selector housing.
I. I. 9 Gearshift Interlock
A brake pedal /shift lever interlock is incorporated in the gearselector mechanism. Theshift lever may only be moved
from the 'P'- Park position if the ignition key switch is in position '11', and the foot brake pedal is applied. The ignition
key cannot be removed from the ignition switch unless the shift lever is in the 'P' -Park position. Once the ignition key
has been removed, the shift lever is locked in the park position.
The gearshift interlock is operated by an electrical solenoid located adjacent to the selector; an override latch is incorpo
- rated into the mechanism to enable the gearshift interlock to be manually overridden in the event of electrical failure
or when towing.
8 Issue 1 August 1994

ZF Automatic Transmissions Service Manual
1.2 HYDRAULIC CIRCUIT DIAGRAMS
Key To Hydraulic Circuit Diagrams (commencing on page IO)
1. Governor 16. 1 - 2
Shift Valve
2. Torque Converter 17.
Clutch
'C' Valve
3. Sump
18. Clutch 'C" Damper
4. Pump 19.
Clutch
'C" Valve
5. Pressure Regulating Valve 20.
2
- 3 Shift Valve
6. Clutch
'B' Valve And Damper 21.
2nd Gear Inhibit
7. Clutch 'D' Valve And Damper 22.
Throttle Valve
8. Reverse Gear Inhibit 23. Converter Clutch Lock-up Control Valve
9. Manual Valve 24.
Converter Clutch Hysteresis Valve
IO. Oil Cooler 25. 3 - 4 Shift
Valve
11. Converter And Reversing Valve 26.
Clutch 'F' Valve And Damper
12. Converter Clutch Damper 27.
Clutch
'A' Damper
13. One
-way Valve
14. Modulator Valve
15. 1st Gear Inhibit
A Clutch'A'
B Clutch'B'
C Clutch'C'
C1 Clutch 'C"
D Clutch'D'
E Clutch'E'
F Clutch'F'
Exhaust
Throttle
Orifice Branch
Main Pressure
Converter Pressure
Throttle Pressure
28. Clutch 'E' Damper
29. Clutch 'F' Inhibit Valve (Reverse)
Vlll HII Governor Pressure
IX - Locking Pressure
X -1- Modulation Pressure
XI - Pump Pressure
XI1 Lubrication Pressure
issue 1 August 1994 9

ZF Automatic Transmissions Service Manual
Problem Possible Cause
1.3.6 Fault Finding Chart (continued)
Action
>hange points at incorrect
;peeds
3eneral
Kick-down' cable sticking
Voisy and no drive after a long
ourney
dery noisy and no drive
3il leaks
3il dripping from the bell
iousing
-eakage between transmission
and oil sump
-eakage between intermediate
date and main housing
:especially at pump pressure
Doint)
3il leak at output
-eakage from cooler pipes
-eakage between main housing
jnd tail housing
3il leak from 'kick-down' cable at
:ransmission end 'Lock
-up'
safety valve sticking.
'Kick
-down' cable setting incorrect.
No 4th gear.
Governor pressure incorrect.
Nipple in throttle cam is worn.
Too much friction in sleeve of
'kick
-down' cable.
Throttle pressure piston sticking.
Oil filter on valve block faulty
Drive plate is worn or broken
Seal ring in pump housing
damaged.
Defective pump 0
-ring.
Pump housing porous.
Converter leaking from welded
seam.
Bolts incorrectly
torqued.
Sump gasket damaged.
Bell housing bolts loose.
Gasket damaged.
Output oil seal damaged
Loose connections.
Pipes damaged.
Cooler leaks.
Loose bolts.
Gasket damaged.
'0' ring connection damaged Service
/ renew valve
block / governor.
Adjust setting.
Check cable adjustment, service
/
renew valve block / governor.
Service
1 renew valve block I governor.
Replace cable.
Replace cable
Service
/ renew valve block.
If there is no burnt lining in the sump,
renew the filter and oil. If debris is
present, renew the transmission.
Renew the drive plate
Renew seal.
Renew
@ring.
Renew pump housing.
Renew converter.
Tighten bolts to specified torque.
Renew sump gasket.
Tighten bolts to specified torque.
Renew gasket.
Renew seal
Tighten connections.
Renew pipes.
Renew cooler.
Tighten bolts.
Renew gasket.
Renew
'0' ring or complete cable
issue 1 August 1994 37

ZF Automatic Transmissions Service Manual
Reverse Gear
Clutches 'B','D' and 'E' are engaged.
As the front planet gear carrier of epicyclic gear SE '9' is
locked, the direction of output shafgt rotation is reversed.
Epicyclic gear set '10' also rotates as a solid block. I
~~~-698
Fig. 1
2.1.4 Transmission Control Unit
The electronichydrauliccontrol unit comprising a series of valve blocks housing a cable-operated manual valve, con- trol pistons and pressure valves is attached to the underside of the transmission housing; the unit controls the oper- ation of the gear train clutches and directs oil pressure to the appropriate system components (refer to illustrations,
pages 43 to 46) to operate the transmission.
The four valve blocks in which the control valves, pistons etc are located, are mounted and connected through a main
gallery plate. The three solenoid valves
MVI, MV2 and MV3 and the pressure regulator operating solenoid are located
on the upper surface of the plate; electrical connections between the solenoids and the transmission and transmission
control unit are via cable harnesses (refer to relevant diagrams and tables for details of the various pin connections).
Operation of the transmission control unit is through an electronic Transmission Control Module
(TCM) which on re-
ceipt of electrical signalsfrom transmission and engine management sources, activates the hydraulic pressure regulat- ing and shift valves via solenoid valves located on the valve block. The gearshift selector transmits movement, via the
selector cable, to the selector lever on the side of the gearbox; this rotates the selector shaft which controls the manual
selector valve. The rotary position of the shaft is monitored by the rotary switch.
42 Issue 1 August 1994

ZF Automatic Transmissions Service Manual
Vehicle speed sensor plus input
Engine speed input
Program switch input
Solenoid valve
MVI output
Pressure control valve PCV output
?. 1.13 Harness Connections
3&31 not used
32
33 Position code
Z input
38 Torque
reduction
T (I) output
34
-37 not used
Vehicle speed sensor minus input
37
55
not used
\I
41 I Kick down switch input
J" i"
Diagnostic L-line
Transmission malfunction indicator lamp
output
not used
Solenoid valves plus input
Vehicle speed sensor screen
Engine torque signal
T(T) input
I IU,MW II
43 not used
44 Oil temperature sensor ground
45 not used
46
Oil temperature sensor input
47 Throttle position input
48 not used
I
not used
Solenoid valve
MV2 output
not used
Power ground input 19
49 Sport mode indicator output
50 Position code X input
51 Diagnostics K
-line
52
-55 not used

J86 I I69 1
Fig.
1 Transmission Control Module Connections - Pin Locations
I1
12
13
: I
17-18
22
-23
t 27-28
25
26
Function I Pin I Function I
Power supply input I 29 I Program switch /Traction control input I
Digital ground input I 39-40 lnot used I
not used
-~
48 Issue 1 August 1994

ZF Automatic Transmissions Service Manual
2.2 HYDRAULIC CIRCUIT DIAGRAMS
Component Engagement
Key
To Hydraulic Diagrams (commencing on page 52)
1. 2.
3. 4.
5. 6.
7.
8. 9. 10. 11. 12. 13.
14. 15. 16.
17.
18.
Oil pump Sump
Torque converter
Olil cooler
Clutch 'A' damper
Clutch 'B' valve and damper
Clutch 'Cl' damper
Clutch 'Cl' valve
Clutch 'C' valve and damper
Clutch
'D' valve and damper
Clutch 'E' damper
Clutch
'F' valve and damper
Reverse locking valve
Shift valve
1 - 2
Shift valve 2 - 3
Shift valve 3 - 4
Safety valve
Pressure valve
1
A Clutch 'A' D Clutch 'D B Clutch 'B' E Clutch 'E'
C Clutch 'C' F Clutch 'F'
C1 Clutch 'C"
19.
20.
21.
22.
23. 24.
25.
26.
27.
28.
29.
30.
31.
32.
33. 34.
35.
G
H J K
Pressure valve 2
Torque converter pressure valve
Lubrication valve
Lubrication valve
Lock
-up control valve
Modulation pressure valve
Main pressure valve
Gear change valve
Solenoid valves
MVllMV2l MV3
Pressure regulator
ECM
- inputs and outputs
Engine torque
Throttle valve Engine speed
(RPM) Transmission speed (RPM) Transmission rotary switch
Oil filter
Torque converter freewheel
(C) Clutch freewheel (D) Clutch freewheel (E) Clutch freewheel
Exhaust - Reduced pressure
=X= Th rott le - Modulation pressure
4= Orifice 2- Sump
- Main pressure - Lubrication pressure
- Converter pressure
Throttle pressure
Issue 1 August 1994 51

ZF Automatic Transmissions Service Manual
a
2.3.6 Fault Finding Chart (continued)
Problem
Starter motor does not operate
'osition 'R' - Reverse
3everse gear inoperative
Slipping and juddering
Harsh
engagement'p-R' chan
'N-R' change (below 1500RPF
engine speed)
Reverse lamp does not
illuminate (bulbs, fuses and
cables functioning correctly)
Possible Cause
Rotary switch adjustment.
Rotary switch wiring fault.
Rotary switch faulty.
Position
'P or 'N' not selected.
vIV2 faulty.
rNire to MV2 earthed.
3il filter dirty.
Damper
'6' faulty.
Clutch
'6' faulty (also no 3rd gear).
Clutch 'D' faulty.
Clutch
'E' faulty (also no engine braking
in 2nd and 3rd gears).
Pressure regulator valve 1 binding
Rotary switch wiring fault.
Rotary switch faulty.
Reverse gear inhibit valve activated.
Main pressure control valve seized (also
no forward drive in 'D' Drive).
'B'Clutch, 'D'Clutch or 'E' Clutch faulty.
Pressure regulator valve 1 binding
'F'Clutch drum sealing rings faulty
causing
loss of 'E' Clutch pressure.
Damper
'6' faulty (also no 2nd to 3rd
shift).
Pressure regulator valve 1 binding
Modulation pressure too high.
Rotary switch faulty.
Rotary switch setting incorrect.
Rotary switch faulty.
Rotary switch wiring fault.
Action
4djust switch.
qectify.
3ectify or renew.
Select 'F" or 'N'.
Renew valve block.
Renew harness.
Clean
/ replace filter and flush out
the
oil cooler and pipes.
Renew valve block.
Renew transmission.
Renew transmission.
Renew transmission.
Renew valve block.
Rectify.
Rectify or renew.
Renew valve block.
Renew valve block.
Renew transmission.
Renew valve block.
Renew transmission.
Renew valve block.
Renew valve block.
Check TCM Fault Codes.
Rectify or renew.
Adjust setting.
Renew.
Rectify.
Issue 1 August 1994 62

ZF Automatic Transmissions Service Manual
Problem Possible Cause
2.3.6 Fault Finding Chart (continued)
e Action
Starter will not operate Rotary
switch faulty or incorrect setting. Rectify
or renew.
3rive not transmitted (neutral
:ondition)
Vehicle moves
Slipping and juddering at start Rotary
switch wiring fault. Rectify 'A'Clutch seized Renew
transmission
Checksecurity System
Harsh engagement
'N'-'D'(under 1500RPM engine
speed)
No 1st to 2nd upshift or 2nd to
1st downshift
No upshift 1st to 2nd
No upshift 2nd to 3rd or
downshift 3rd to 2nd
No upshift 2nd to 3rd
3il filter dirty.
Main pressure control valve seized.
Low oil level.
'A'Clutch faulty.
'D'Clutch one-way clutch slips. ~
'A'Clutch faulty
Low oil level.
'A'Clutch faulty.
'A'Clutch damper faulty (5).
Throttle pot. volts high.
Rotary switch faulty
/ out of adjustment.
MVI wire earthed(remains in 2nd gear).
MVI faulty.
Control circuit fault.
Shift valve
1-2 seized.
Pressure reducing valve
1 seized.
Speed sensor or connectors faulty.
Clutches
'Cl' and 'C' faulty
MV2 wire earthed (remains in 2nd gear).
MV2 faulty.
Shift valve 2
-3 seized.
Speed sensor faulty.
'B'Clutch faulty Clean
/ replace
filter.
Renew valve block.
Check oil level.
Renew transmission.
Renew transmission.
Renew transmission.
Check oil level.
Renew transmission.
Renew valve block.
Check throttle pot. volts.
Rectify or renew.
Renew harness.
Renew valve block.
Check TCM Diagnostics
/ rectify.
Renew valve block.
Renew valve block.
Check connections, rectify or
renew.
Renew transmission
Renew harness.
Renew valve block.
Renew valve block.
Rectify or renew.
Renew transmission
Issue 1 August 1994 63

ZF Automatic Transmissions Service Manual
0
3il in bell housing
2.3.6 Fault Finding Chart (continued)
Oil pump seal leaking.
Oil pump 0
-ring leaking.
Pump housing leaking.
Converter seam leaking.
Problem Possible Cause Action
:onverter clutch
-eakage between gearbox and
sump
Leakage between intermediate
date and gearbox
Leakage at harness plug
:onnector
Leakage at drive flange
:Iutch engagement speed
ncorrect
Loose fastening screws.
Sump gasket faulty.
Bell housing to gearbox screws loose
Connector 'O'ring faulty
Rear oil seal faulty
ingagement
too hard
Jo clutch engagement
Ionverter clutch engaging at
dle (engine will not idle in
'D')
Control circuit fault.
Speed sensor faulty.
Valve body problem.
Converter unit faulty
Control circuit fault
MV3 faulty.
Converter clutch valve seized.
Converter faulty. Pressure reducing valve
1 seized.
Incorrect oil level.
Oil filter not sealing.
Control circuit fault.
MV3 faulty.
MV3 wire earthed.
Converter clutch valve
sticking.
Check TCM Diagnostics / rectify
fault.
Check TCM Diagnostics
1 renew
speed sensor.
Renew valve body
Renew converter unit
Check TCM Diagnostics
1 rectify
fault.
Renew valve block.
Renew valve block.
Renew converter.
Renew valve block.
Check oil level.
Check 0
-ring etc.
Check TCM Diagnostics
/ rectify
fault.
Renew valve block.
Renew harness.
Renew valve block.
Renew oil pump seal.
Renew 0
-ring.
Renew oil pump.
Renew converter.
Torque tighten.
Renew gasket.
Torque tighten
Renew
'0' ring
Renew oil seal
Issue 1 August 1994 66
. _.~ -