1994 JAGUAR XJ key

ZF Automatic Transmissions Service Manual
The torque converter acts in all four forward gears and in reverse. The converter lock-up clutch closes in 4th gear at
a point depending on road speed and accelerator position; engine power is then transmitted by purely mechanical
means.
A low-loss oil pump in the front of the transmission housing supplies the converter, the automatic gear shift and the
lubrication circuit; oil is drawn from a sump in the bottom of the gear train housing through a filter. The pump drive
gear is keyed to the converter impeller hub and therefore turns when the engine is running, thereby pressurizing the
oil.
Selected ratios
Di, 31, 21
1.1.2 Four-speed Epicychc Gear Train
The torque converter drives a mechanical epicyclic gear train providing four forward ratios and reverse. Individual ra-
tios are obtained by coupling togetherthevarious parts of the geartrain by means of hydraulically actuated multi-disc
clutches and brakes; built in freewheels permit gear shifts without any interruption of the power flow. Operation of the
clutches and gear sets is described
in sub-section 1.1.3.
Each epicyclic (or planetary) gear set comprises a central, sungear, an annulus and a planetary carrier which supports
four small planet gears or pinions. Two gear sets are used in this transmission. A compound gear set comprising front
annulus and planet carrier, rear annulus and planet carrier and a common sungear transmits the drive
in all gears ex- cept REVERSE; a single planetary carrier, annulus and sungear transmits the fourth gear drive. The table below shows
the resulting clutch operation
in the selected gear ratios.
Resulting clutch operation
A Clutch drives annulus clockwise
E Clutch
& OWC drives output shaft clockwise
D2,32,22
D3,33, 23
04
R
Park, Neutral
A Clutch drives annulus clockwise
C1 Clutch holds sungear against anti-clockwise
C Clutch
& OWC holds sungear against anti-clockwise
A Clutch drives annulus clockwise
B Clutch drives sungear clockwise
C Clutch
& OWC holds sungear against anti-clockwise
A Clutch drives annulus clockwise
B Clutch drives sungear clockwise
C Clutch & OWC holds sungear against anti-clockwise
B Clutch drives sungear clockwise
D Clutch holds carrier against clockwise
E Clutch
& OWC drives output shaft anti-clockwise
E Clutch
& OWC applied (hydraulics)
OWC = one way clutch
2 Issue 1 August 1994

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
The torque converter acts in all four forward gears and in reverse. The converter lock-up clutch closes in 4th gear at
a point depending on road speed and accelerator position; engine power is then transmitted
by purely mechanical
means.
A low
-loss oil pump in the front of the transmission housing supplies the converter, the automatic gear shift and the
lubrication circuit; oil is drawn from a sump in the bottom of the gear train housing through a filter. The pump drive
gear is keyed to the converter impeller hub and therefore turns when the engine is running, thereby pressurizing the
oil.
2.1.2 Four-speed Epicyclic Gear Train
The torque converter drives a mechanical epicyclic gear train providing four forward ratios and reverse. Individual ra-
tios are obtained by coupling together the various parts of the gear train by means of solenoid-operated, hydraulically
actuated multi-disc clutches and brakes; built in freewheels permit gear shifts without any interruption of the power
flow.
For information on the operation of the solenoids, clutches, brakes and freewheels, refer to the table below and the
schematic diagrams shown overleaf.
A parking lock pawl is provided at the rear of the gear train, operating on a toothed wheel attached to the output shaft;
the parking lock is operated from the selector (position
'P) by actuator rod.
An electro
-magnetic sensor detects output shaft revolutions by means of a toothed disc attached to the shaft; one rev- olution of the shaft is equal to 36 pulses. The electrical signal from the sensor is passed, via a screened cable, to the
TCM.
R
Park,
Neutral
Solenoid ~
MV2
MVI, MV2
MVI, MV3
MV2
-
MV2
OWC
= one way clutch
Resulting clutch operation
A Clutch drives annulus clockwise
D Clutch OWC holds F carrier against shaft clockwise
E Clutch & OWC drives output shaft clockwise
A Clutch drives annulus clockwise
C1 Clutch holds sungear against anti-clockwise
C Clutch
& OWC holds sungear against anti-clockwise
A Clutch drives annulus clockwise
B Clutch drives sungear clockwise
C Clutch
& OWC holds sungear against anti-clockwise
A Clutch drives annulus clockwise
B Clutch drives sungear clockwise
C Clutch
& OWC holds sungear against anti-clockwise
B Clutch drives sungear clockwise
D Clutch holds carrier against clockwise
E Clutch & OWC drives output shaft anti-clockwise
E Clutch & OWC applied (hydraulics)
40
Issue 1 August 1994

ZF Automatic Transmissions Service Manual
2.1.6 Transmission Rotary Switch
This switch is located on a square extension of the transmission selector shaft and is linked to the shift lever via the
selector cable. The switch comprises a selector bar which moves across a series of copper segments located on the
switch quadrant. The copper segments are set out in seven bands, each band providing an electrical output or com
- bination of outputs to the TCM.
The electrical outputs to the TCM are in the form of a three
-digit code which takes up three of the seven bands of the
quadrant; the remaining four bands are used for reverse, ground and start inhibit.
2.1.7 Decoder Module
The decoder module, located on the right hand side of the J-gate assembly, is used to translate the three-digit codes
from the rotary transmission switch into single-line functions to feed the illumination module and to provide the fol-
lowing information:
. Cruise control, ie when cruise control can or cannot be engaged.
. Indication when the vehicle is not in 'P' Park.
. Provide the ECM with a Park/ Neutral signal.
2.1.8 Performance Mode Switch
This switch, located on the shift lever surround, provides two alternative shift patterns:
. 'Normal Mode' -for everyday use,
. 'Sport Mode'- gear changes take place at higher road speeds in order to enhance performance.
Note: Torque converter 'lock-up' occurs in fourth gear in each mode.
2. I. 9 'Kick-down' Mechanism
'Kick-down' is activated by the final travel of the accelerator pedal which contacts a floor-mounted switch located be- hind the pedal. Operation of the switch provides a signal to the TCM that a downward change is required. The switch
is adjustable to ensure that the pedal does not overtravel and stretch the cable.
2.1.10 Reverse Safefy Inhibit
If 'R' Reverse is selected when the vehicle is travelling forwards at more than 5 mile / h, solenoid valve MV2 will be
energised to prevent engagement of reverse gear.
2.1.11 Gearshift hterlock
A brake pedal /gearshift interlock is incorporated in the gear selector mechanism. The gear selector lever may only
be moved from the P - Park position if the ignition key switch is in position II and the foot brake 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.
2.1.12 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.
issue 1 August 1994 47

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

E
Fau;t diagnosis
ZF 4HP 22
Electrical checks,
33
Engine tune, 33
Fault finding chart, 34
Initial checks, 33
Road test, 33
Stall test, 33
Electrical tests, 61
Engine tune, 60
Fault finding chart, 61
Initial checks, 60
Road test, 61
Stall test, 60
ZF 4HP 24 E
Foreword, ii
G
General description
ZF4HP22
Epicyclic gear train, 2
Gear train clutches operation, 3
Gearshift interlock, 8
Gearshift selection, 8
Output shaft extension housing, 4
Starter inhibit switch, 8
Throttle valve mechanism, 8
Torque converter, 1
Transmission control unit, 4
Control layout schematic illustration, 46
Decoder module, 47
Epicyclic gear train, 40
Gear train clutches operation, 41
Gearshift interlock, 47
Harness connections, 48
Kick-down mechanism, 47
Main harness connector
ZF
4HP 24 E
12-way, 50
Sway, 50
Performance mode switch, 47
Reverse safety inhibit, 47
Rotary switch connector pins, 49
Rotary switch harness, 49
Starter inhibit switch, 47
TCM connector pins, 48
Torque converter, 39
Transmission control module, 46
Transmission control unit, 42
Transmission rotary switch, 47
H
Hydraulic circuit diagrams
‘1 ’ - 1 st, full throttle, 32
‘1’ - 21-14 idling, 31
‘1 ’ - 3rd, idling, 30
‘2’ - 2nd, full throttle, 29
‘2’ - 3rd, idling, 28
‘3’ - 3rd, full throttle, 26
‘3’ - 3rd, kickdown, 27
‘3’ - 3rd, part throttle, 25
ID’- drive, Ist, full throttle, 14
ZF 4HP 22
‘D’ - drive, lst, idle, 13
‘D’ - drive, lst, kickdown, 15
‘D’ -drive, 2nd, full throttle, 17
‘D’ - drive, 2nd, idle, 16
‘D’ - drive, 2nd, kickdown, 18
‘D’ -drive, 3rd, full throttle, 20
‘D’ - drive, 3rd, kickdown, 21
‘D’ -drive, 3rd, part throttle, 19
‘D’ -drive, 4th, full throttle lock-up, 24
‘D’ -drive, 4th, part throttle, 22
‘D’ - drive, 4th, part throttle lock-up, 23
‘N’ - neutral, 12
‘P’ - park, 10
‘R‘ - reverse, 11
Key, 9
‘1’ - Ist, 59
‘D’ - drive, 1 st, 55
‘D’ - drive, 2nd, 56
‘D’ - drive, 3rd, 57
‘D’ - drive, 4th, lock-up, 58
‘N’ - neutral, 54
‘P’ - park, 52
‘R‘ - reverse, 53
Key, 51
ZF 4HP 24 E
S
Service data, iii
Service materials, iii
Service operations
ZF 4HP 22, Not yet available, 68
ZF 4HP 24 E, Not yet available, 68
Service tools & equipment, iii
T
Torque tightening specifications, iii