Published: 11-May-2011
Automatic Transmission/Transaxle - TDV6 3.0L Diesel /V8 5.0L Petrol/V8 S/C 5.0L Petrol - Transmission Description - Overview
Description and Operation
OVERVIEW
The ZF 6HP28 transmission is an electronically controlled, hydraulically operated, six speed automatic unit. The hydraulic and
electronic control elements of the transmission, including the TCM (transmission control module), are incorporated in a single
unit located inside the transmission and is known as 'Mechatronic'.
5.1 L SC (supercharger) and 3.0L diesel models use an uprated derivative of the ZF 6HP28 transmission used in the 5.0L
naturally aspirated models.
The ZF 6HP28 transmission has the following features:
Designed to be maintenance free
Transmission fluid is 'fill for life'
The torque converter features a controlled slip feature with electronically regulated control of lock-up, creating a smooth
transition to the fully locked condition
Shift programs controlled by the TCM Electronic park lock, controlled by the TCM, with a mechanical emergency release ASIS (adaptive shift strategy), to provide continuous adaptation of shift changes to suit the driving style of the driver,
which can vary from sporting to economical.
Connected to the ECM (engine control module) via the high speed CAN (controller area network) bus for communications
Default mode if major faults occur
Diagnostics available from the TCM via the high speed CAN bus.
The transmission selections are made using the rotary JaguarDrive selector in the floor console and two paddle switches on the
steering wheel. For additional information, refer to 307-05B Automatic Transmission/Transaxle External Controls - 5.0L/3.0L
Diesel).
1 Transmission selected gear status 2 MIL (malfunction indicator lamp) 3 Message center The instrument cluster is connected to the TCM via the high speed CAN bus. Transmission status is transmitted by the TCM and displayed to the driver in one of two displays in the instrument cluster. For additional information, refer to 413-01
Instrument Cluster.
Malfunction Indicator Lamp
The MIL (malfunction indicator lamp) is located in the tachometer in the instrument cluster. Transmission related faults which
may affect the vehicle emissions output will illuminate the MIL.
The MIL is illuminated by the ECM (engine control module) on receipt of a relevant fault message from the TCM on the high speed CAN. The nature of the fault can be diagnosed using a Jaguar approved diagnostic system which reads the fault codes stored in the TCM memory.
Transmission Status Display
The transmission status display is located in a LCD (liquid crystal display) at the top of the instrument cluster, between the
speedometer and the tachometer. The LCD shows the JaguarDrive selector position or the selected gear when in manual 'Jaguar Sequential Shift' mode.
The following table shows the displays and their descriptions.
Symbol Description P Park selected R Reverse selected N Neutral selected D Drive selected S Sport mode selected 1 1st gear selected (manual Jaguar sequential shift mode) 2 2nd gear selected (manual Jaguar sequential shift mode) 3 3rd gear selected (manual Jaguar sequential shift mode) 4 4th gear selected (manual Jaguar sequential shift mode) 5 5th gear selected (manual Jaguar sequential shift mode) 6 6th gear selected (manual Jaguar sequential shift mode) The message center is located in the lower center of the instrument cluster. The message center is a LCD to relay vehicle status and operating information to the driver and can display messages relating to a number of the vehicle systems. If a
transmission fault occurs, the message center will display the message 'GEARBOX FAULT'.
TRANSMISSION CONTROL MODULE
The TCM outputs signals to control the shift control solenoid valve and the EPRS (electronic pressure regulating solenoid) to control the hydraulic operation of the transmission.
The TCM processes signals from the transmission speed and temperature sensors, the ECM and other vehicle systems. From the received signal inputs and pre-programmed data, the module calculates the correct gear, torque converter clutch setting
and optimum pressure settings for gear shift and lock-up clutch control.
The ECM supplies the engine management data over the high speed CAN bus. The TCM requires engine data to efficiently control the transmission operation, for example; flywheel torque, engine speed, accelerator pedal angle, engine temperature.
The steering angle sensor and the ABS (anti-lock brake system) module also supply data to the TCM on the high speed CAN bus. The TCM uses data from these systems to suspend gear changes when the vehicle is cornering and/or the ABS module is controlling braking or traction control.
Using the signal inputs and the memorized data, the TCM control program computes the correct gear and torque converter lock-up clutch setting and the optimum pressure settings for gear shift and lock-up clutch control. Special output-side modules
(power output stages, current regulator circuits), allow the TCM to control the solenoid valves and pressure regulators and consequently precisely control the hydraulics of the automatic transmission. In addition, the amount and duration of engine
interventions are supplied to the engine management by way of the CAN bus.
The transmission has a fully electronic JaguarDrive selector with no Bowden cable connection to the transmission. The
transmission selections are made using a rotary JaguarDrive selector which rises from the floor console once the engine is
running. Rotation of the JaguarDrive selector to any of the five positions is sensed by the TCM via the high speed CAN bus. The TCM then reacts according to the selected position. The 'S' (sport) position selection allows the TCM to operate the transmission using the semi-automatic 'Jaguar Sequential Shift'.
Gear selections are sensed by the TCM when the driver operates the steering wheel paddle switches. Once the JaguarDrive selector position is confirmed, the TCM outputs appropriate information on the high speed CAN bus.
If the JaguarDrive selector is in 'D', 'Jaguar Sequential Shift' is temporary and will cancel after a time period or can be cancelled
by pressing and holding the + paddle for approximately 2 seconds.
If the JaguarDrive selector is in 'S', 'Jaguar Sequential Shift' is permanent and can only be cancelled by pressing and holding
the + paddle for approximately 2 seconds or by moving the JaguarDrive selector to the 'D' position.
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The TCM can be reprogrammed using a Jaguar approved diagnostic system using a flash code. The TCM processor has a 440 kb internal flash memory. Of this capacity, approximately 370 kb are used by the basic transmission program. The remainder,
approximately 70 kb is used to store vehicle-specific application data.
Engine Stall
If the vehicle stalls it will coast down in gear, with the transmission providing drive to the engine. A restart can be attempted
at this point and the engine may start and the driver can continue.
If the coast down speed reduces such that the speed of the engine is less than 600 rev/min, the transmission will go to
neutral, D illumination will flash in the instrument cluster. The driver needs to select neutral or park and then press the brake
pedal to restart the engine.
If the start/stop button is pressed when driving, the message ENGINE STOP BUTTON PRESSED is displayed in the message
center but there will be no change to the ignition state. If the driver requires to switch off the engine, the start/stop button
must be pressed for a second time. The engine will be stopped and will be back driven by the transmission as the vehicle
coasts down. When the engine speed is less than 600 rev/min the transmission engages neutral (flashing D illumination in the
instrument cluster). When vehicle speed is less than 2 km/h (1.2 mph) Park is engaged. The JaguarDrive selector automatically
rotates back to its lowered P position and the vehicle ignition is switched off.
The park engagement is prevented in a stall case as the ignition power is on and D was the last selected gear. The park
engagement speed at ignition off is from the least value of the wheel speeds (CAN signal) and transmission output speed (internal signal).
TRANSMISSION Component Description
The transmission comprises the main casing which houses all of the transmission components. The main casing also
incorporates an integral bell housing.
A fluid pan is attached to the lower face of the main casing and is secured with bolts. The fluid pan is sealed to the main
casing with a gasket. Removal of the fluid pan allows access to the Mechatronic valve block. The fluid pan has a magnet
located around the drain plug which collects any metallic particles present in the transmission fluid.
A fluid filter is located inside the fluid pan. If the transmission fluid becomes contaminated or after any service work, the fluid
pan with integral filter must be replaced.
The integral bell housing provides protection for the torque converter assembly and also provides the attachment for the
gearbox to the engine cylinder block. The torque converter is a non-serviceable assembly which also contains the lock-up clutch
mechanism. The torque converter drives a crescent type pump via drive tangs. The fluid pump is located in the main casing,
behind the torque converter.
The main casing contains the following major components:
Input shaft
Output shaft
Mechatronic valve block which contains the solenoids, speed sensors and the TCM Three rotating multiplate drive clutches
Two fixed multiplate brake clutches
A single planetary gear train and a double planetary gear train.
1 Blades 2 Stator held – fluid flow redirected 3 Stator rotates freely 4 Roller 5 Converter at coupling speed 6 Fluid flow from turbine 7 Converter multiplying 8 Fluid flow from impeller 9 Drive from engine 10 Impeller 11 Stator 12 Turbine 13 Output to transmission Fluid emitted from the impeller acts on the turbine. If the turbine is rotating at a slower speed than the fluid from the impeller,
the fluid will be deflected by the turbine blades in the path 'A'. The fluid is directed at and deflected by the stator blades from
path 'B' to path 'C'. This ensures that the fluid is directed back to the pump in the optimum direction. In this condition the
sprag clutch is engaged and the force of the fluid on the stator blades assists the engine in rotating the impeller.
As the rotational speed of the engine and therefore the turbine increases, the direction of the fluid leaving the turbine changes
to path 'D'. The fluid is now directed from the turbine to the opposite side of the stator blades, rotating the stator in the
opposite direction. To prevent the stator from resisting the smooth flow of the fluid from the turbine, the sprag clutch releases,
allowing the stator to rotate freely on its shaft.
When the stator becomes inactive, the torque converter no longer multiplies the engine torque. When the torque converter
reaches this operational condition it ceases to multiply the engine torque and acts solely as a fluid coupling, with the impeller
and the turbine rotating at approximately the same speed.
The stator uses a sprag type, one way, freewheel clutch. When the stator is rotated in a clockwise direction the sprags twist
and are wedged between the inner and outer races. In this condition the sprags transfer the rotation of the outer race to the
inner race which rotates at the same speed. www.JagDocs.com
DTC Description Possible Cause Action P0781-07
1-2 Shift - Mechanical
Failures
Gear Ratio Monitoring.
Mechanical Failures Check and correct oil level. Clear DTC. If code
re-detects suspect Transmission (Gearbox) internal
fault. Install a new Transmission as required, refer to
the new module/component installation note at the top of the DTC Index P0781-77
2-1 Shift - commanded
position not reachable
Gear Ratio Monitoring.
Mechanical Failures Check and correct oil level. Clear DTC. If code
re-detects suspect Transmission (Gearbox) internal
fault. Install a new Transmission as required, refer to
the new module/component installation note at the top of the DTC Index P0782-07
2-3 Shift - commanded
position not reachable
Gear Ratio Monitoring.
Mechanical Failures Check and correct oil level. Clear DTC. If code
re-detects suspect Transmission (Gearbox) internal
fault. Install a new Transmission as required, refer to
the new module/component installation note at the top of the DTC Index P0782-77
3-2 Shift - commanded
position not reachable
Gear Ratio Monitoring.
Mechanical Failures Check and correct oil level. Clear DTC. If code
re-detects suspect Transmission (Gearbox) internal
fault. Install a new Transmission as required, refer to
the new module/component installation note at the top of the DTC Index P0783-07
3-4 Shift - Mechanical
Failures
Gear Ratio Monitoring.
Mechanical Failures Check and correct oil level. Clear DTC. If code
re-detects suspect Transmission (Gearbox) internal
fault. Install a new Transmission as required, refer to
the new module/component installation note at the top of the DTC Index P0783-77
3-4 Shift - commanded
position not reachable
Gear Ratio Monitoring.
Mechanical Failures Check and correct oil level. Clear DTC. If code
re-detects suspect Transmission (Gearbox) internal
fault. Install a new Transmission as required, refer to
the new module/component installation note at the top of the DTC Index P0784-07
4-5 Shift - Mechanical
Failures
Gear Ratio Monitoring.
Mechanical Failures Check and correct oil level. Clear DTC. If code
re-detects suspect Transmission (Gearbox) internal
fault. Install a new Transmission as required, refer to
the new module/component installation note at the top of the DTC Index P0784-77
4-5 Shift - commanded
position not reachable
Gear Ratio Monitoring.
Mechanical Failures Check and correct oil level. Clear DTC. If code
re-detects suspect Transmission (Gearbox) internal
fault. Install a new Transmission as required, refer to
the new module/component installation note at the top of the DTC Index P0798-1A
Pressure Control Solenoid C
Electrical - Circuit Resistance
Below Threshold
Pressure control solenoid
C Circuit resistance
below threshold Suspect the Transmission control module. Install a
new Transmission control module as required, refer to
the new module/component installation note at the
top of the DTC Index P0798-1E
Pressure Control Solenoid C
Electrical - Circuit Short to
Ground
Pressure control solenoid
C electrical circuit short
to ground Suspect the Transmission control module. Install a
new Transmission control module as required, refer to
the new module/component installation note at the
top of the DTC Index P0798-21
Pressure Control Solenoid C
Electrical - signal amplitude
< minimum
Pressure Control Solenoid
C Electrical signal
amplitude < minimum Suspect the Transmission control module. Install a
new Transmission control module as required, refer to
the new module/component installation note at the
top of the DTC Index P0814-62 Transmission Range Display
Circuit - signal compare
failure
Transmission Range
Display Circuit signal
compare failure Suspect the Transmission control module. Install a
new Transmission control module as required, refer to
the new module/component installation note at the
top of the DTC Index P0826-08
Up and Down Switch circuit -
Bus Signal Message Failures
Invalid CAN signal from
BCM/Instrument cluster
Stuck switch
CAN bus circuit fault Check Central junction box and Instrument cluster for
stored DTCs. Check gear change switches for correct
operation. Refer to circuit diagrams and check CAN bus
for a circuit fault P0826-81
Up and Down Switch Circuit -
invalid serial data received
Invalid Can signal from
BCM / Instrument cluster
Stuck switch
CAN Bus Circuit fault Check Central junction box and Instrument cluster for
stored DTCs. Check Gear Change Switches for correct
operation. Refer to Circuit diagrams and check CAN
Bus for Circuit fault P0826-88
Up and Down Switch Circuit -
Bus off
SWM to BCM /
Instrument cluster LIN
Bus failure Check Central junction box and Steering Wheel Ice
Switches for stored DTCs. Refer to Circuit diagrams
and check LIN Bus for Circuit fault
6 Clockspring 7 Steering wheel audio switches 8 Upshift paddle switch 9 Downshift paddle switch 10 Instrument cluster 11 JaguarDrive selector
JAGUARDRIVE SELECTOR System Operation
Rotation of the JaguarDrive selector to any of the five positions is sensed by the TCM (transmission control module) via the
high speed CAN bus. A LIN bus connection is also provided, but is only used in the event of a CAN bus failure as a back-up. The TCM then reacts according to the selected position. The JaguarDrive selector is a magnetic system using Hall effect sensors to determine the position of the selector.
The S (sport) position selection allows the TCM to operate the transmission using the semi-automatic Jaguar sequential shift. Gear selections are sensed by the TCM when the driver operates the steering wheel paddle switches. Once the JaguarDrive selector position is confirmed, the TCM outputs appropriate information on the high speed CAN bus which is received by the instrument cluster to display the gear selection information in the message center.
Refer to: Information and Message Center (413-08 Information and Message Center, Description and Operation).
The paddles can also be used on a temporary basis when the JaguarDrive selector is in the D (drive) position to override the
automatic gear selection if required.
PARK INTERLOCK AND NEUTRAL LOCK
Neutral lock is a requirement for the JaguarDrive selector. The selector is always locked at ignition on when the engine is not
running, except after an engine stall when the selector is not in P (park) or N (neutral).
If, when driving with the JaguarDrive selector in S, D or R (reverse) at a speed of more than 5 km/h (3 mph), the driver selects
P or N:
Without the brake pedal pressed, the JaguarDrive selector will be immediately locked once the vehicle speed falls to
below 5 km/h (3 mph).
With the brake pedal pressed, the JaguarDrive selector will remain locked for as long as the brake pedal remains
pressed, regardless of vehicle speed.
The transmission will only engage park once the vehicle speed is less than 2 km/h (1 mph).
If the driver selects N and releases the brake pedal with a vehicle speed of less than 5 km/h (3 mph), the JaguarDrive selector
will be locked 2 seconds after N is selected. The selector will remain locked until the driver presses the brake pedal again.
To ensure that a driver request to change from a non-driving range (N for example) to a driving range (D for example), the park
interlock and neutral lock features are used in conjunction with the intermediate position.
If the transmission receives a range change request without the brake pedal pressed, the TCM initiates a soft lock function. The transmission will remain in park or neutral, depending on the starting position.
If a transmission position letter is flashing in the message center and the vehicle has no drive, the driver must:
Press the brake pedal.
Reselect N or P on the JaguarDrive selector.
Select the required driving range, ensuring that the brake pedal is pressed.
Rocking Function
The rocking function compliments the neutral lock function. For all changes from a non-driving range to a driving range, it is
necessary to press the brake pedal (to release either the park interlock or neutral lock).
In situations where the driver will require to change the gear selection from R to D, or from D to R, without brake pedal input
(car park maneuvering, 3 point turns or 'rocking' the vehicle from a slippery surface for example), the rocking function gives a 2
second lock delay when N is selected on the JaguarDrive selector and the brake pedal is not pressed.
Intermediate Position
If the JaguarDrive selector is rotated slowly from P to S and back to position P with the brake pedal pressed, the R or D
position display letter in the message center will flash and the transmission will remain in park or neutral depending on the
previous starting position of the selector.
If the brake pedal is released when R or D is flashing in the message center and the JaguarDrive selector is rotated to the R or
D position, the required range will not be selected and the transmission will remain in park or neutral, depending on the
previous starting position. This feature is known as soft lock.
If the driving range letter in the message center is flashing and the vehicle has no drive, the driver should depress the brake
pedal to reselect N or P, and then select the required driving range while the brake pedal remains pressed.
6 Clockspring 7 APP (accelerator pedal position) sensor 8 Electric throttle actuator 9 Brake lamp/brake test switch 10 Adaptive speed control radar sensor 11 Diagnostic socket 12 Instrument cluster 13 TCM (transmission control module) 14 Adaptive speed control module
SPEED CONTROL System Operation
The speed control system uses inputs from the brake lamp/brake test switch, the APP sensor, the ECM and the ABS module.
Speed control is operated by the driver using only the steering wheel switches. When speed control is active, the ECM regulates the PWM (pulse width modulation) signals to the fuel injectors to adjust the fuel supply as required to maintain the
set speed.
During speed control operation, the ECM controls vehicle speed by adjusting fuel injection duration and timing. When the accelerator pedal is pressed with speed control active, the ECM outputs a calculated throttle angle signal in place of the actual throttle angle signals produced by the APP sensor. The calculated throttle angle is derived from fuel demand.
The minimum set speed for speed control is 18 mph (30 (km/h). Speed control is automatically suspended if the following
conditions apply:
Vehicle speed falls below 18 mph (30 km/h)
The brake pedal is pressed
The cancel button is pressed
Neutral, park or reverse gear is selected
The difference between actual speed and the set speed is too great
If the engine speed becomes near to the red line (maximum engine speed)
If the accelerator pedal is used to accelerate beyond the set speed for too long.
ADAPTIVE SPEED CONTROL
The adaptive speed control system comprises the following components:
Adaptive speed control sensor
Adaptive speed control module
Steering wheel control switches
ECM
Electric throttle actuator
ABS module and pump Adaptive speed control warning indicator.
The adaptive speed control system uses a forward looking radar sensor to scan the road ahead, looking for objects that are
moving at a different rate to itself. When a target is identified the adaptive speed control system will monitor the time gap
between it and the target vehicle. When that gap falls below a set driver selected level the adaptive speed control system will
intervene slowing the vehicle by backing off the throttle and/ or applying the brakes, until the correct gap is attained. The
driver can chose between four gap settings, 1, 1.4, 1.8 and 2.2 seconds.
The system will detect but not react to the following:
Vehicles in the oncoming lane
Stationary vehicles
Pedestrians
Vehicles not in the same lane.
Adaptive speed control is active when the vehicle is moving. Adaptive Speed Control only functions when a set speed is
entered in normal speed control mode. The adaptive speed control system only intervenes with the set speed when it detects
a target vehicle, and then only if the minimum time gap is breached.
It is important to note that the system is intended for use in limited driving situations, does not remove control and
responsibility from the driver, and at all times can be quickly overridden. The adaptive speed control system is not a collision
warning system and will not react to stationary objects. The system does not operate below a minimum speed of
approximately 30 km/h (20 mph) since it is unsuitable for use in cities or congested traffic. The system is best suited to main
roads/ highways with gradual bends.
The ECM, throttle body and throttle control are unchanged from those used for non adaptive speed control variants.
The adaptive speed control system is based on the use of a front mounted radar sensor. The sensor transmits a 1.5° wide
beam forward of the vehicle and detects the returning signals reflected off other vehicles and objects ahead.
The 1.5° wide radar beam is mechanically scanned at a rate of 10 sweeps/second across a total arc of 15° centered on the
. M–2
Benchmark noise against non-complaint
vehicle. . Trip (fuel) computer N–1
Check for consistent display (during test
drive) of valid 'Rolling Odometer' count in
Self-Diagnostic Mode/ETM test 24. Displays ---- , INV or 255 if message is not
received, or if received data is invalid. . N–2
Check that installed wheels and tires are
standard Jaguar fit. Confirm fitted wheel
size in IDS, 'ADD REMOVE ACCESSORY'
section. Non standard wheels and tires or incorrectly set
wheel size may lead to Odometer increment
inaccuracies. This will impact the distance
accumulators, which in turn affects the rolling
average, fuel economy and range values. Trip
distance accumulation will also be incorrect. . N–3
Consider noting odometer value and
resetting fuel computer system. Advise
customer to conduct brim-to-brim fuel
tank test. Use collected information to
determine if system accurate. . Column adjust O-1
Check with IDS for DTCs related to powered column system. . O-2
Check cluster battery supply voltage and
ground resistance. Check for loose
connections. . O-3
Check power column motors supply voltage. . O-4
Check power column switch for physical damage. . Passive Anti-Theft
System (PATS)
indicator P–1
Check for three second prove out when
vehicle start button is pressed. . . P–2
Check for loose connections/wiring continuity. . . P–3 Check ignition switch for physical damage. . Cluster illumination Q–1
Check for loose connections/wiring continuity. . . Q–2 Check dimmer switch operation. . Cluster backlight operation R–1
Is the backlight on other components inoperative. . . R–2 Check dimmer switch operation. . . R–3
Check for loose connections/wiring continuity. . Chime/tone operation S–1 Check vehicle configuration. . . S–2
Utilize lights ON, ignition OFF, door open warning to verify chime operation. . . S–3 Check appropriate sensing circuit. . Continuous chime/tone T–1 Check appropriate sensing circuit. . Unexpected chime operation U–1 Check vehicle configuration. . Message centre display illumination V–1
Is the backlight 'ON' and other components dim? . . V–2
Does the lighting level of other
components change when dimmer adjusted? . Message centre
display issue W–1
Perform Self-Diagnostic Mode test/ETM
tests 5 to 9, to prove out LCD display
function. . Message centre
missing lines X–1
Perform Self-Diagnostic Mode test/ETM
tests 5 to 9, to prove out LCD display
function. . Message centre
incorrect message Y–1 What is the message? . . Y–2
Check for open circuit/shorts in wiring to
related warning light trigger (module,
sensor, switch). . Cluster/connectivity Z–1 Check cluster battery and ignition wiring. . . Z–2 Check cluster grounds. . . Z–3 Disconnect/reconnect cluster. . . Z–4
Attempt to enter Self-Diagnostic
Mode/ETM to prove cluster response to inputs. . No crank AA–1
Check with IDS for presence of related
DTCs. . . AA–2
Is there a Passive Anti-Theft System (PATS) flash code? . . AA–3
Does the vehicle crank with the other passive key? .