2010 JAGUAR XFR ignition

Published: 11-May-2011
Engine Ignition - V8 5.0L Petrol/V8 S/C 5.0L Petrol - Engine Ignition - Component Location
Description and Operation


NOTE: RHD (right-hand drive) naturally aspirated installation shown; other installations similar.
COMPONENT LOCATION



Item Description 1 RFI (radio frequency interference) suppressor 2 ECM (engine control module) 3 Spark plug (8 off) 4 Ignition coil (8 off)

Published: 11-May-2011
Engine Ignition - V8 5.0L Petrol/V8 S/C 5.0L Petrol - Engine Ignition - Overview
Description and Operation

OVERVIEW

The engine ignition system is a coil-on-plug, single spark system controlled by the ECM (engine control module). An iridium
tipped spark plug is installed in each combustion chamber, between the inlet and exhaust valves, and an ignition coil is
installed on each spark plug. A RFI (radio frequency interference) suppressor is connected to the power feed to the ignition
coils.

Published: 11-May-2011
Engine Ignition - V8 5.0L Petrol/V8 S/C 5.0L Petrol - Engine Ignition - 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 (ignition relay)) 4 CJB (central junction box) 5 RFI suppressor 6 LH (left hand) cylinder bank ignition coil (4 off) 7 RH (right hand) cylinder bank ignition coil (4 off) 8 ECM

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
Engine Ignition - V8 5.0L Petrol/V8 S/C 5.0L Petrol - Engine Ignition
Diagnosis and Testing

Principles of Operation

For a detailed description of the engine ignition system and operation, refer to the relevant Description and Operation section
of the workshop manual. REFER to: (303-07B Engine Ignition - V8 5.0L Petrol/V8 S/C 5.0L Petrol)

Engine Ignition (Description and Operation), Engine Ignition (Description and Operation), Engine Ignition (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 checked and/or the donor vehicle.


NOTE: Check and rectify basic faults before beginning diagnostic routines involving pinpoint tests.

1. Verify the customer concern.
2. Visually inspect for obvious signs of mechanical and electrical damage.

Visual Inspection
Mechanical Electrical
Engine oil level
Cooling system coolant level
Fuel level
Fuel contamination/grade/quality
Exhaust gas recirculation (EGR) valves
Fuses
Wiring harness
Loose or corroded electrical connectors
Ignition coils
Sensor(s)
Engine Control Module (ECM)
Transmission Control Module (TCM)
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, alternatively check for
Diagnostic Trouble Codes (DTCs) and refer to the DTC Index.

Symptom Chart

Symptom Possible Causes Action Engine cranks, but does not
fire
Engine breather system
disconnected/restricted
Ignition system
Fuel system
Electronic engine control Ensure the engine breather system is free from restriction
and is correctly installed. Check for ignition system, fuel
system and electronic engine control DTCs and refer to the
relevant DTC Index Engine cranks and fires, but
will not start
Evaporative emissions purge
valve
Fuel pump
Spark plugs
HT short to ground (tracking)
check rubber boots for
cracks/damage
Ignition system Check for evaporative emissions, fuel system and ignition
system related DTCs and refer to the relevant DTC Index Difficult cold start
Engine coolant level/anti-
freeze content
Battery
Electronic engine controls
Exhaust Gas Recirculation
(EGR) valve stuck open
Fuel pump
Purge valve Check the engine coolant level and condition. Ensure the
battery is in a fully charged and serviceable condition.
Check for electronic engine controls, engine emissions, fuel
system and evaporative emissions system related DTCs
and refer to the relevant DTC Index

Symptom Possible Causes Action Difficult hot start
Injector leak
Electronic engine control
Purge valve
Fuel pump
Ignition system
EGR valve stuck open Check for injector leak, install new injector as required.
Check for electronic engine controls, evaporative emissions,
fuel system, ignition system and engine emission system
related DTCs and refer to the relevant DTC Index Difficult to start after hot
soak (vehicle standing,
engine off, after engine has
reached operating
temperature)
Injector leak
Electronic engine control
Purge valve
Fuel pump
Ignition system
EGR valve stuck open Check for injector leak, install new injector as required.
Check for electronic engine controls, evaporative emissions,
fuel system, ignition system and engine emission system
related DTCs and refer to the relevant DTC Index Engine stalls soon after start
Breather system
disconnected/restricted
ECM relay
Electronic engine control
Ignition system
Air intake system restricted
Air leakage
Fuel lines Ensure the engine breather system is free from restriction
and is correctly installed. Check for electronic engine
control, ignition system and fuel system related DTCs and
refer to the relevant DTC Index. Check for blockage in air
filter element and air intake system. Check for air leakage
in air intake system Engine hesitates/poor
acceleration
Fuel pressure, fuel pump,
fuel lines
Injector leak
Air leakage
Electronic engine control
Throttle motor
Restricted accelerator pedal
travel (carpet, etc)
Ignition system
EGR valve stuck open
Transmission malfunction Check for fuel system related DTCs and refer to the
relevant DTC Index. Check for injector leak, install new
injector as required. Check for air leakage in air intake
system. Ensure accelerator pedal is free from restriction.
Check for electronic engine controls, ignition, engine
emission system and transmission related DTCs and refer
to the relevant DTC Index Engine backfires
Fuel pump/lines
Air leakage
Electronic engine controls
Ignition system
Sticking variable camshaft
timing (VCT) hub Check for fuel system failures. Check for air leakage in
intake air system. Check for electronic engine controls,
ignition system and VCT system related DTCs and refer to
the relevant DTC Index Engine surges
Fuel pump/lines
Electronic engine controls
Throttle motor
Ignition system Check for fuel system failures. Check for electronic engine
controls, throttle system and ignition system related DTCs
and refer to the relevant DTC Index Engine detonates/knocks
Fuel pump/lines
Air leakage
Electronic engine controls
Sticking VCT hub Check for fuel system failures. Check for air leakage in
intake air system. Check for electronic engine controls and
VCT system related DTCs and refer to the relevant DTC
Index No throttle response
Electronic engine controls
Throttle motor Check for electronic engine controls and throttle system
related DTCs and refer to the relevant DTC Index Poor throttle response
Breather system
disconnected/restricted
Electronic engine control
Transmission malfunction
Traction control event Air
leakage Ensure the engine breather system is free from restriction
and is correctly installed. Check for electronic engine
controls, transmission and traction control related DTCs and
refer to the related DTC Index. Check for air leakage in
intake air system DTC Index

For a list of Diagnostic Trouble Codes (DTCs) that could be logged in the Engine Control Module (ECM), please refer to Section
303-14. REFER to:

Electronic Engine Controls (303-14C Electronic Engine Controls - V8 5.0L Petrol, Diagnosis and Testing), Electronic Engine Controls (303-14D Electronic Engine Controls - V8 S/C 5.0L Petrol, Diagnosis and Testing).

Published: 11-May-2011
Engine Ignition - V8 5.0L Petrol/V8 S/C 5.0L Petrol - Ignition Coil-On-Plug V8 S/C 5.0L Petrol
Removal and Installation

Removal

NOTES:


Removal steps in this procedure may contain installation details.


Some variation in the illustrations may occur, but the essential information is always correct.

1. Refer to: Battery Disconnect and Connect (414-01, General Procedures).

2. Refer to: Engine Cover - 5.0L, Vehicles With: Supercharger (501-05,
Removal and Installation).

3. Refer to: Secondary Bulkhead Panel RH - 5.0L/3.0L Diesel (501-02,
Removal and Installation).

4. CAUTIONS:


Be prepared to collect escaping coolant.


Make sure that all openings are sealed. Use new
blanking caps.










5. www.JagDocs.com

Published: 11-May-2011
Engine Emission Control - V8 5.0L Petrol/V8 S/C 5.0L Petrol - Engine Emission
Control
Diagnosis and Testing

Principles of Operation

For a detailed description of the engine emission control system and operation, refer to the relevant Description and Operation
section of the workshop manual. REFER to: (303-08C Engine Emission Control - V8 5.0L Petrol/V8 S/C 5.0L Petrol)

Engine Emission Control (Description and Operation), Engine Emission Control (Description and Operation), Engine Emission Control (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 checked and/or the donor vehicle.


NOTE: Check and rectify basic faults before beginning diagnostic routines involving pinpoint tests.
1. Verify the customer concern.

2. Visually inspect for obvious signs of mechanical or electrical damage.

Visual Inspection
Mechanical Electrical
Exhaust gas recirculation system
Breather hoses
Positive crankcase ventilation valve
Fuel level
Fuel contamination/grade/quality
Throttle body
Fuses
Loose or corroded electrical connectors
Exhaust Gas Recirculation (EGR) valve
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, alternatively check for
Diagnostic Trouble Codes (DTCs) and refer to the DTC Index.

Symptom Chart

Symptom Possible Causes Action Difficult to
start cold
Battery
Crankshaft Position (CKP)
sensor
Exhaust Gas Recirculation
(EGR) valve stuck open
Fuel system
Evaporative emissions purge
valve For battery information, CKP sensor, fuel system and purge valve tests,
refer to relevant workshop manual section. Check the EGR valve. Engine stalls
soon after
start
Breather system
disconnected/restricted
Engine Control Module (ECM)
relay
MAF sensor
Ignition system
Air filter restricted
Air leakage
Fuel lines Check the engine breather hoses, PCV, etc. Check the Engine Control
Module (ECM) relay operation. For MAF sensor, ignition system tests, air
intake and fuel line information, refer to relevant workshop manual
section. Poor throttle
response
APP sensor malfunction
TP sensors
ECT sensor
MAF sensor
Transmission malfunction
Traction control event Air
leakage For APP, TP, ECT, MAF sensor tests, intake system checks and
transmission information, refer to relevant workshop manual section.
Check the breather system hoses, PCV, etc.