2010 JAGUAR XFR Ejb

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

Published: 11-May-2011
Intake Air Distribution and Filtering - V8 S/C 5.0L Petrol - Intake Air
Distribution and Filtering - System Operation and Component Description
Description and Operation

Control Diagram

NOTE: A = Hardwired



Item Description 1 Battery 2 BJB (battery junction box) (250 A megafuse) 3 EJB (engine junction box) (EMS high current relay) 4 Tuning valve 5 ECM (engine control module)

Published: 11-May-2011
Electronic Engine Controls - V8 S/C 5.0L Petrol - Electronic Engine Controls - System Operation and Component Description
Description and Operation

Control Diagram

NOTE: A = Hardwired; D = High speed CAN (controller area network) bus.
CONTROL DIAGRAM SHEET 1 OF 2



Item Description 1 Battery 2 BJB (battery junction box) (250 A megafuse) 3 EJB (engine junction box) 4 ECM

Published: 11-May-2011
Automatic Transmission/Transaxle - TDV6 3.0L Diesel /V8 5.0L Petrol/V8 S/C 5.0L Petrol - Transmission Description - System Operation and Component Description
Description and Operation

Control Diagram

NOTE: A = Hardwired; B = K bus; D = High speed CAN (controller area network) bus; O = LIN (local interconnect
network) bus



Item Description 1 Battery 2 BJB (battery junction box) (250 A megafuse) 3 EJB (engine junction box) 4 CJB (central junction box)

Published: 11-May-2011
Automatic Transmission/Transaxle External Controls - TDV6 3.0L Diesel /V8 5.0L Petrol/V8 S/C 5.0L Petrol - External Controls - System Operation and
Component Description
Description and Operation

Control Diagram

NOTE: A = Hardwired; D = High speed CAN (controller area network) bus; O = LIN (local interconnect network) bus



Item Description 1 Battery 2 BJB (battery junction box) (250 A megafuse) 3 CJB (central junction box) 4 EJB (engine junction box) 5 TCM (transmission control module)

rear window heater switch is pressed or the engine stops.

Automatic operation during a journey is initiated when low ambient air temperatures are experienced and the vehicle has been
travelling for a set period of time above a threshold speed. In this instance, no feedback is given to the driver to inform him
the rear window heater is operational (the switch LED is not illuminated). The duration of heater operation is variable depending on the ambient air temperature, vehicle speed and the amount of time the vehicle has been travelling.

Windshield Heater (Where Fitted)

Windshield heater operation is only enabled when the engine is running. The ATC module controls operation of the windshield heater using two relays in the EJB (engine junction box). When windshield heater operation is required, the ATC module broadcasts a message to the CJB on the medium speed CAN bus. On receipt of the message, the CJB energizes the relays by providing a ground path for both relay coils. This allows a battery feed to flow across the relays to power the windshield left
and right heater elements.
There are two modes of windshield heater operation; manual and automatic.

Manual operation is activated by pressing the windshield heater switch on the integrated control panel. When the switch is
pressed, the status LED in the switch illuminates and the windshield heater elements are energized. Manual operation is discontinued when the windshield heater switch is pressed a second time, 5 minutes have elapsed (the heating phase), or the
engine stops. If manual operation is discontinued by the engine stopping, the previous heating phase is resumed if the engine
is re-started within 30 seconds.

There are two variants of automatic operation; automatic operation at the start of a journey and automatic operation during a
journey.

Automatic operation at the start of a journey is initiated if the ambient air temperature is below 5 °C (41 °F). In this instance,
the switch LED is illuminated and the heater elements are energized for 6.5 minutes. Automatic operation is discontinued if the windshield heater switch is pressed or the engine stops.

Automatic operation during a journey is initiated when low ambient air temperatures are experienced and the vehicle has been
travelling for a set period of time above a threshold speed. In this instance, no feedback is given to the driver to inform him
the windshield heater is operational (the switch LED is not illuminated) and the duration of operation is variable depending upon the ambient air temperature, vehicle speed and the amount of time the vehicle has been travelling.

Exterior Mirror Heaters

Operation of the exterior mirror heaters is fully automatic and not controllable by the driver. Exterior mirror heater operation is
determined by ambient air temperature and windshield wiper status. When ambient air temperature reaches a pre-determined
level, the ATC module broadcasts an exterior mirror heating request to the door modules over the medium speed CAN bus. On receipt of this message, the door modules provide feed and ground connections to both exterior mirror heater elements.

The amount of time the exterior mirror heaters are operational increases if the windshield wipers are switched on. This ensures
the mirrors remain mist free in damp and wet conditions, where there is an increased risk of misting.

Seat Heaters (Where Fitted)

There are four seat heater settings available; off, 1, 2 and 3, which can be selected on the home and climate control screens
of the TSD. The heat setting is relayed to the vehicle occupants through a graduated display on the TSD.

Operation of the heated seats is controlled by the ATC module. When the ATC module receives a heating request from the TSD, it broadcasts a message to the CJB over the medium speed CAN bus. The CJB then provides a hardwired 12 V supply to the three heater elements in the related front seat. The heater elements, two in the seat cushion and one in the seat squab,
are wired in series. The ATC module monitors seat temperature using a temperature sensor located in each seat cushion. The CJB provides the temperature sensors with a 5 V supply. The level of the returned voltage back to the CJB is proportional to the seat temperature. The value of the return signal is broadcast to the ATC module, over the medium speed CAN bus, which allows it to control the seat temperature to the required level. The ATC module will suspend or disable operation of the seat heaters if any of the following occur:

Battery voltage exceeds 16.5 ± 0.3 V for more than 5 seconds. Seat heating is re-enabled when battery voltage
decreases to 16.2 ± 0.3 V.
If a short or open circuit is detected.
If the seat heat temperature rises significantly above the target temperature setting.

The graduated display on the TSD remains illuminated until the seat heaters are turned off or the engine stops. If the engine
is restarted within 30 seconds the seat heater resumes the previous heating level.

Published: 11-May-2011
Instrument Cluster - Instrument Cluster - System Operation and Component Description
Description and Operation

Control Diagram

NOTE: A = Hardwired; D = High speed CAN (controller area network) bus; N = Medium speed CAN bus; O = LIN (local interconnect network) bus



Item Description 1 Battery 2 BJB (battery junction box) 3 EJB (engine junction box) 4 CJB (central junction box) 5 Sun load sensor (alarm LED (light emitting diode))

Instrument Cluster - Instrument Cluster
Diagnosis and Testing

Principles of Operation Published: 22-Mar-2013

For a detailed description of the Instrument Cluster, refer to the relevant Description and Operation sections in the workshop
manual. REFER to: (413-01 Instrument Cluster)

Instrument Cluster (Description and Operation), Instrument Cluster (Description and Operation), Instrument Cluster (Description and Operation).
Inspection and Verification


CAUTION: Diagnosis by substitution from a donor vehicle is NOT acceptable. Substitution of control modules does not
guarantee confirmation of a fault, and may also cause additional faults in the vehicle being tested and/or the donor vehicle.
1. Verify the customer concern.
2. Visually inspect for obvious signs of damage and system integrity.

Visual Inspection
Mechanical Electrical
Fluid level(s)
Accessory installations
Fuse(s)
Wiring harness
Electrical connector(s)
Instrument cluster
Central Junction Box (CJB)
Engine Junction Box (EJB)
Driver Door Module (DDM)
Engine Control Module (ECM)
3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to
the next step.
4. If the cause is not visually evident, verify the symptom and refer to the Symptom Chart.

Symptom Chart

The instrument cluster contains a self-diagnostic mode known as engineering test mode (ETM). This can be used to show the
status of the instrument cluster inputs as well as a number of other useful features.

When in the ETM, the Message Centre displays internal data that can be cycled through. All functions except the message
centre display will continue to operate normally unless otherwise noted.

This document is to be used in conjunction with the instrument cluster ETM (see relevant section within this document) and
the Integrated Diagnostic System (IDS) facility; this does not supersede or replace the IDS facility.

Go directly to the 'Area of Concern/Symptom' that indicates the customer concern(s) and perform the actions described within
the relevant section(s):

Area of Concern/Symptom Diagnostic
Ref. No.
Actions
Notes Warning lights A-1
Perform instrument cluster Self-Diagnostic
Mode/ETM test 3. When this test is ended the warning lamps
currently required to be 'ON' will remain
illuminated. Multiple warning lights
'ON' B–1
Check with IDS for DTCs related to
identified vehicle system(s). . . B–2
Check instrument cluster battery and
ignition wiring - refer to circuit diagrams. Specifically check continuity of Standard
Corporate Protocol (SCP) and Controller Area
Network (CAN) lines. . B–3 Check instrument cluster grounds. . . B–4 Check fuses in battery junction box. . . B–5 Check for harness traps in facia. . . B–6
Perform instrument cluster Self-Diagnostic
Mode/ETM test 3. Frost/ice warning illuminated in mixed red and
amber; therefore colour differs from other
warning lamps. When this test is ended,
warning lamps currently required to be 'ON' will
remain illuminated. . B–7
Check for open circuit/shorts in wiring to
related warning lamp trigger (module,
sensor, switch). .