2010 JAGUAR XFR Power distribution box

Published: 11-May-2011
Front Disc Brake - TDV6 3.0L Diesel /V8 5.0L Petrol/V8 S/C 5.0L Petrol - Front Disc Brake - System Operation and Component Description
Description and Operation

Control Diagram

NOTE: A = Hardwired



Item Description 1 Battery 2 Megafuse (250 A) 3 Front brake pad wear sensor 4 Rear brake pad wear sensor 5 Instrument cluster 6 CJB (central junction box) 7 Power distribution box

Published: 11-May-2011
Rear Disc Brake - TDV6 3.0L Diesel /V8 5.0L Petrol/V8 S/C 5.0L Petrol - Rear
Disc Brake - System Operation and Component Description
Description and Operation

Control Diagram

NOTE: A = Hardwired



Item Description 1 Battery 2 Megafuse (250 A) 3 Front brake pad wear sensor 4 Rear brake pad wear sensor 5 Instrument cluster 6 CJB (central junction box) 7Powerdistributionbox

1 RH (right hand) charge air cooler 2 Engine 3 LH (left hand) charge air cooler 4 Expansion hose connection (with engine cooling system) 5 Charge air radiator 6 Charge air coolant pump
System Operation
Electrical power for the charge air coolant pump is supplied from the intercooler water pump relay in the power distribution box.
When the intercooler water pump relay is energized, it connects power from the battery, via the BJB (battery junction box)
and CJB (central junction box), to the charge air coolant pump. Operation of the intercooler water pump relay is controlled by
the ECM (engine control module). The intercooler water pump relay is energized continuously while the ignition is in power
mode 6.

When the charge air coolant pump is running, coolant flows from the pump outlet through the charge air coolers, the charge air
radiator and back to the pump inlet. Supercharger Cooling Flow Diagram

GENERAL System Operation

The ignition coils are supplied with electrical power from the battery via a 250 A megafuse in the BJB (battery junction box)
and the ignition relay in the EJB (engine junction box). The control signal for the ignition relay is supplied by the CJB (central
junction box).

The ECM (engine control module) sends a separate signal to each ignition coil to trigger the power stage switching. The ECM calculates the dwell time from the battery voltage and engine speed, to ensure a constant energy level is produced in the
secondary coil each time the power stage is switched. This ensures sufficient spark energy is available without excessive
primary current flow, which avoids overheating and damage to the ignition coils.
The ECM calculates the ignition timing for individual cylinders from: Engine speed
Camshaft position
Engine load
Engine temperature
The knock control function
The shift control function
The idle speed control function.



IGNITION COILS Component Description



The ignition coils are installed in the cylinder head covers, under the NVH (noise, vibration and harshness) covers. Each
ignition coil locates on a spark plug and is secured to the related cylinder head cover with a single screw. Each ignition coil
incorporates a three pin electrical connector for connection to the engine harness.

Each ignition coil contains a primary and a secondary winding. The primary winding receives electrical power from the ignition
relay in the power distribution box. A power stage in the primary winding allows the ECM to interrupt the power supply, to induce a voltage in the secondary winding and thus the spark plug. A diode in the ground side of the secondary winding
reduces any undesirable switch-on voltage, to prevent misfiring into the intake manifold. The power stage limits the maximum
voltage and current in the primary winding, to protect the power stage and limit the voltage in the secondary winding. www.JagDocs.com

SUPERCHARGER System Operation

At closed or partially open throttle positions, the bypass valve is fully open, allowing a flow of air from the SC (supercharger)
outlet back to the inlet side. This results in little or no pressure increase across the SC. Progressive opening of the throttle reduces the depression downstream of the electric throttle. This is sensed by the pneumatic actuator, which moves to close
the bypass valve. As the bypass valve closes there is a corresponding increase in the outlet pressure from the SC, which increases engine power output.

NOISE FEEDBACK SYSTEM

Sound waves from the RH (right-hand) intake manifold are filtered by the calibrated orifice in the inlet pipe connection on the
symposer. The sound waves make the paddle oscillate and generate pulsations in the outlet chambers. When the pneumatic
valve is open, the pulsations are transmitted through the outlet pipe and feedback tube to the resonator in the passenger
compartment.

The tuning valve of the noise feedback system receives a power feed from the power distribution box and is connected to
ground through the ECM (engine control module). At lower engine loads and speeds the ECM keeps the ground open circuit and the tuning valve is de-energized closed. Atmospheric pressure is sensed at the pneumatic valve through the vent cap on the
tuning valve, which keeps the pneumatic valve closed and prevents sound from the symposer entering the feedback system.

At higher engine loads and speeds the ECM connects the tuning valve to ground. The tuning valve energizes, blanks off the atmospheric vent and opens the vacuum line between the brake vacuum system and the pneumatic valve. The depression in
the brake vacuum system is sensed at the pneumatic valve, which opens and allows sound from the symposer into the
feedback system.
The status of the pneumatic valve at various engine loads and speeds is given below:

Pneumatic Valve Status

NOTE: Values are for valve opening with increasing engine load and speed. Deduct 0.05 g/rev and 50 rev/min for valve
closing with decreasing engine load and speed.


Engine Load: g/rev Engine Speed: rev/min 0 500 1000 2500 3000 4000 5800 6500 1.30 Closed Closed Closed Closed Closed Closed Closed Closed 1.35 Closed Closed Closed Closed Closed Closed Closed Closed 1.40 Closed Closed Closed Closed Closed Closed Closed Open 1.60 Closed Closed Closed Closed Closed Closed Closed Open 1.80 Closed Closed Closed Closed Closed Closed Closed Open 2.50 Closed Closed Closed Closed Closed Open Open Open 3.00 Closed Closed Closed Closed Closed Open Open Open 3.50 Closed Closed Closed Open Open Open Open Open

Touch screen display (TSD) 6 Integrated control panel 7 Information control module 8 ATC (automatic temperature control) module 9 Face/Feet distribution stepper motor 10 RH (right-hand) temperature blend stepper motor 11 LH (left-hand) temperature blend stepper motor 12 Windshield (defrost) distribution stepper motor 13 Blower control module 14 RJB (rear junction box) 15 Blower
System Operation
Operation of the heating and ventilation system is controlled by the ATC module. Refer to: Control Components (412-01 Climate Control, Description and Operation).
The system can be operated in automatic or manual mode, with temperature settings selected using the switches on the
integrated control panel.

When the engine is running, coolant is constantly circulated through the heater core by the engine coolant pump and the
auxiliary coolant pump. Where fitted, the auxiliary coolant pump is energized by the CJB on receipt of medium speed CAN bus signals from the ATC module. The CJB broadcasts auxiliary coolant pump status over the medium speed CAN bus for use by other vehicle systems.

The blower is supplied with power by the blower relay on the RJB and connected to ground via the blower control module. The blower control module regulates the voltage across the blower motor to control blower speed. The voltage set by the blower
control module is controlled by a PWM (pulse width modulation) signal from the ATC module. The ATC module uses a feedback signal from the blower control module to monitor blower speed.
Refer to: Control Components (412-01 Climate Control, Description and Operation).


Heater Assembly Component Description

The heater assembly controls the temperature and flow of air supplied to the air distribution ducts. The heater assembly is
mounted on the vehicle centerline, between the instrument panel and the engine bulkhead.

The heater assembly consists of a casing that contains an A/C (air conditioning) evaporator, a heater core, two air distribution
control doors and two temperature blend control doors. On 2.7L diesel vehicles, the heater assembly also contains an electric
booster heater.
Refer to: Electric Booster Heater (412-02 Auxiliary Climate Control, Description and Operation).
Mounted on the heater casing are four stepper motors. Each of the stepper motors is connected to either an air distribution
control door or a temperature blend control door.
The A/C evaporator is part of the A/C system. Refer to: Air Conditioning (412-01 Climate Control, Description and Operation).
The heater core provides the heat source to warm the air supplied to the passenger compartment. The heater core is an
aluminum two pass, fin and tube heat exchanger, and is installed across the width of the heater housing. Two aluminum tubes
attached to the heater core extend through the engine bulkhead and connect to the engine cooling system. For additional
information, refer to:
Engine Cooling (303-03A, Description and Operation),
Engine Cooling (303-03B Engine Cooling - V6 3.0L Petrol, Description and Operation), Engine Cooling (303-03C, Description and Operation).

Air Inlet Duct

The air inlet duct connects the fresh air inlet in the engine bulkhead to the heater assembly. The air inlet duct is installed
behind the instrument panel on the passenger side.

The air inlet duct consists of a casing that contains a pollen filter, an air inlet door, a blower and a blower control module. A
recirculation air inlet is incorporated into the casing. A servo motor is mounted on the casing and connected to the air inlet
door, to allow selection between fresh and recirculated air.
Refer to: Control Components (412-01 Climate Control, Description and Operation). The pollen filter is part of the air distribution and filtering system.
Refer to: Air Distribution and Filtering (412-01 Climate Control, Description and Operation).
The blower regulates the volume of air flowing through the air inlet duct to the heater assembly. The blower consists of an
open hub, centrifugal fan and an electric motor.
The blower control module regulates the power supply to the blower motor. The blower control module is installed in the air

8 LH licence plate lamp 9 LH fog lamp 10 RH fog lamp 11 High mounted stop lamp 12 RH tail lamp assembly 13 LH tail lamp assembly 14 RH door mirror side repeater 15 LH door mirror side repeater 16 RH front door module 17 Auxiliary lighting switch 18 LH front door module 19 Lighting control switch - LH steering column multifunction switch 20 Rain/light sensor 21 Instrument cluster 22 RH headlamp assembly - side lamp and side marker lamp (if fitted) 23 CJB 24 LH headlamp assembly - side lamp and side marker lamp (if fitted)
System Operation CENTRAL JUNCTION BOX (CJB) AND REAR JUNCTION BOX (RJB)
The CJB is an integrated unit which controls body functions and power distribution. The CJB is located on the RH 'A' pillar. The RJB also controls body functions and power distribution and is located in the RH side of the luggage compartment. Central Junction Box

The CJB receives inputs from the following switches via the instrument cluster and the medium speed CAN bus: LH Steering column multifunction switch - Side lamp position
- Headlamp position
- Automatic (AUTO) position
- Timer delay positions
- Turn signal indicators
- Headlamp flash and main beam positions.
The CJB receives direct inputs from the following components: Stop lamp switch
Rain/light sensor.
The CJB provides power supplies to the following lamps:
LH and RH front side lamps LH and RH front side marker lamps (if fitted) LH and RH static bending lamp (if fitted) LH and RH low beam headlamp LH and RH high beam headlamp. Rear Junction Box
The RJB provides power supplies to the following lamps:
LH and RH tail lamps LH and RH stop lamps LH and RH front turn signal indicators LH and RH rear turn signal indicators LH and RH licence plate lamps LH and RH side marker lamps High mounted stop lamp
Rear fog lamps
Reverse lamps.

The RJB also provides a power supply to the LH and RH door modules. The door modules use the power supply to activate the turn signal indicator side repeater lamps located in the door mirrors, on receipt of a medium speed CAN bus message from the RJB. Circuit Protection

The CJB and the RJB provide circuit protection for their respective lighting circuits. The exterior lighting circuits are protected

Instrument cluster
High speed CAN
(controller area network) bus Receives data from other vehicle systems to provide
information to the driver. Also functions as the gateway for the bus systems. Instrument panel. Steering column
High speed CAN bus Controls the locking and unlocking of the steering
column. Upper steering column. Diagnostic socket
High speed CAN bus Allows the transfer of vehicle information using a
Jaguar approved diagnostic system or other diagnostic tool. In the lower instrument panel
on the driver's side, adjacent
to the start control module. RCM (restraints control module) High speed CAN bus Controls the deployment of the supplementary
restraint components. At rear of floor console. TCM (transmission
control module) High speed CAN bus Controls automatic transmission operation.
Inside the transmission and
accessible via the fluid pan. ECM (engine control
module) High speed CAN bus Controls engine management and fuel system
operation. Rear of the engine
compartment on the
bulkhead. ABS (anti-lock brake
system) High speed CAN bus Controls all aspects of the braking system
Rear of the engine
compartment on the
bulkhead. Headlamp leveling
module High speed CAN bus Controls the static dynamic headlamp leveling
function. In the lower instrument panel, behind the glovebox. Occupant classification
system control module (NAS only) High speed CAN bus Detects when a passenger is in the front passenger
seat and can determine their size and weight. Below the front passenger
seat. Adaptive damping
control module High speed CAN bus Controls the adjustment of the dampers.
Below the front passenger
seat. Electronic Parking Brake
(EPB) module High speed CAN bus Controls the application and release of the electronic
parking brake. In the luggage compartment,
above the RH (right-hand)
wheel arch. Pedestrian protection
module High speed CAN bus Controls and monitors the pedestrian protection system. LH (left-hand) 'A' pillar. Adaptive speed control
module High speed CAN bus Controls the vehicle's road speed in relation to other
vehicles when in speed control mode. Behind the instrument panel
on the driver's side. Electronic transmission
selector High speed CAN bus Allows the driver to electronically select the required
automatic transmission mode. Transmits driver
selections to the TCM. In the floor console. Jaguar Drive control
module High speed CAN bus Controls the Jaguar Drive function and communicates
with other system modules. Integral with the electronic
transmission selector
software in the floor console. CJB
Medium speed CAN bus Controls body functions and power distribution. On RH 'A' pillar. Diagnostic socket
Medium speed CAN bus Allows the transfer of vehicle information using a
Jaguar approved diagnostic system or other diagnostic tool. In the lower instrument panel
on the driver's side, adjacent
to the start control module. Passenger door module
Medium speed CAN bus Controls window and locking functions. In the front passenger door. Parking aid module
Medium speed CAN bus Controls the parking aid system.
In the LH side of the luggage compartment, adjacent to
the keyless vehicle module. www.JagDocs.com