1998 JAGUAR X308 turn signal

Spin
the wheel by hand and check the meter display.
3
Doe

s the sensor generate a voltage?
Yes GO to E2
.
No

If the WSS ring is in good condition, install a new WSS.
REFER to: Rear Wheel Speed Sensor
(20
6-09 Anti-Lock Control, Removal and Installation).
E2

: CHECK THE WSS SIGNAL CIRCUIT CONTINUITY
Make sure the ignition is off. 1
Di

sconnect the ABS module connector, LF27.
2
Meas

ure the resistance between LF27
, pin 21 (U) and LA02, pin 01 (U).
3
I
s the resistance less than 5 ohms?
Yes GO to E3
.
No

Repair the high resistance circui t. This circuit includes intermediate connector, LA02. Refer to the
electrical guides. Clear the DTC, check for normal operation.
E3
: CHECK THE WSS RETURN CIRCUIT CONTINUITY
Meas

ure the resistance between LF27
, pin 22 (U) and LA02, pin 02 (U).
1
I
s the resistance less than 5 ohms?
Yes The WSS and circuits are OK. Check for DTCs indicating a possible module failure.
No Repair the high resistance circui t. This circuit includes intermediate connector, CA29. Refer to the
electrical guides. Clear the DTC, check for normal operation.
P
INPOINT TEST F : CONT
ROLLER AREA NETWORK (CAN) INTEGRITY TEST
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
F

1: CHECK THE NETWORK INTEGRITY
FROM THE DIAGNOSTIC SOCKET
M
easure the resistance between pins 06 (Y) and 14 (G) of the diagnostic socket.
1
I

s the resistance 60 ohms?
Yes The CAN system is OK. Check for DTCs indicating a fault elsewhere.
No Check the CAN system for open an d short circuits. Refer to the electrical guides. Clear the DTC,
check for normal operation.

diverter val
ve (if fitted) and oil filter.
Main
bearings
which are grooved in the upper positions and plain in
the lower positions. They are manufactured from
aluminium / tin material.
A c
rankshaft with under
cuts and rolled fillets for extra strength.
Fracture
-split connecting rods in sintered-forged steel.
Brackets
bolted to the front of
the cylinder
block are used to mo unt all accessories.
A sin
gle, seven ribbed vee belt
drives the accessories.
An au
tomatic belt tensioner for the front accessory drive,
incorporating a wear indicator.
An advanced en
gine management system inco
rporating electronic throttle control.
The un
it meets the requirements of the CARB OBDII USA legislation.
Ancillary Systems
The an
ci
llary systems, driven by the engine, each have a
detailed Description and Operation along with Diagnostic
Procedures, and Removal and Installation instructions ; refer to the following sections of this manual:
Power Steeri
ng Pump - Section 211-02
Ai
r Conditioning Compressor - Sectio
n 412-03
Engine
C
ooling Pump - Section 303-03
Generator
- Sectio
n 414-02
The drive belt, idler pulley and automatic tensioner are described in Section 303-05.
The engine starting system is described in Section 303-06.
En
gine Management and Emission Control System
Engine Control Modu
le (ECM)
Engine
management and exhaust emissions are controlled by the ECM, which has the
following main functions:
Fu
el injection
Idle
s
peed
Ignition Ev

aporative loss system
Engine
cooling fans Clim
ate control compressor clutch demand
The microprocessor within the ECM receiv es signals from various sensors and other modules and uses a pre-determined
program to compute engine management functions.
Adaptive functions are incorporated in the ECM to cater for co ntinuous adjustments to its computations to suit prevailing
conditions. Because the system also controls emissions to suit all modes, neither CO levels nor idle speed require service
attention or adjustment, except if an error should occur.
On Board Diagnostics are controlled by the ECM with the continuous monitoring of incoming signals and the subsequent
verification against what the module expects to 'see'. Should a si gnal be incorrect or missing, the ECM will substitute a fixed
value to provide the 'limp home mode' and alert the driver of the problem. Fixed values may be adopted for:
Transmission oil
temperature
Mechanica
l
guar
d position
Throttle blade angle Camshaft position

Inta
k
e air temperature
Diagnostic trouble codes (DTC), including OBD II codes, are stored in the ECM memo ry and can be read by an appropriate
retrieval tool.
Should either the ECM or TCM fa il, ensure that the control housing cooling fan is operating correctly. Failure of the cooling
fan MUST be rectified before renewing a control module and details of a fa n failure should accompany a returned control
module.

E
ngine Management System Components
Electronic Throt
tle
The
electronic throttle assembly, in resp
onse to signals from both the driver and the ECM, adjusts idle speed, sets the
throttle valve to the position requested by the driver's accelerator / throttle pedal, cruise and traction control, power
limitation and catalyst warm-up.
Mass
Air Flow Meter
The sensor i
s located in the air flow mete
r assembly and outputs an analogue voltag e to the ECM. This sensor measures air
flow into the engine inlet system and is calibrated to measure kg / hour.
In
take Air Temperature
Th
e intake air temperature sensor is loca
ted in the air flow meter assembly and outputs an analogue voltage to the ECM.
The ECM will substitute a default value eq ual to 50°C should this sensor fail.
Fuel Injectors
The eigh
t bottom fed fuel injectors are located in the fuel rails. Th
e fuel injectors are electromagnetic solenoid valves
controlled by the ECM. The pulse time for the injector combined with the fuel pr essure determines the volume of fuel
injected to the manifold.
Fue
l Delivery
The fu
el pump provides fuel to the fuel rail where the circulat
ing pressure is controlled by a pressure regulator valve; excess
fuel is returned to the fuel tank.
The pressure regulator valve is controlled by manifold depression so that fuel delivery pressure is maintained at
approximately 3 bar above manifold pressure.
Fuel Pump
Relay
The ECM controls thi

s component for normal
engine running. The security system may disable this relay via communication
with the ECM.
Fuel Lev
el Sensing
The tank fuel

is measured by the fuel le
vel sensor . This signal is used by the ECM as an in put to certain diagnostics.
Eva
porative Valve
Excess vapour

formed in the fuel tank is
absorbed into the evaporative emission pu rge control canister. While the engine is
running, the fuel absorbed in the canister is gradually purged back into the engine. The rate of purging is governed by
engine operating conditions and vapour concentration level. Operating conditions which affect the purge rate are:
2—Purge
valve
3—Engine

torque reduction
4—E

lectronic throttle assembly
5—Coo

ling fans
6—Ignition amplifier driver
7—Engine overspeed
8—Cli

mate control compressor clutch
9—O

BDII information (J1962, CAN, ISO)

10—F
uel pump relay
11—Heat

ed oxygen sensor
12—Vari

able valve timing
13—MIL sw

itching



ECM Out
puts
It

em
Par
t Number
De
scription
1—Exhaus

t gas recirculation

Fuel D
istribution
Fuel is supplied to th
e engine
via eight fuel injectors (one pe r cylinder). The injectors are located in two fuel rails which r un
the length of each cylinder bank and ar e integral with the air intake manifold.
Fuel pumped from the tank enters a feed pipe at the rear of bank 2. Fuel flow is along bank 2 fuel rail, across the top front
of the engine (cross-over pipe) and through bank 1 fuel rail, the unused fuel re turning to the tank via a pressure regulator.
The fuel injectors are each controlled electrically from the engine control module (ECM).
A test valve is fitted to the cross-over pipe connecting the fu el rails at the front of the intake manifold. This valve allows the
fuel system to be depr essurized during servicin g and troubleshooting.
Fuel Injector

Eight, side-fed, dual straight-jet fuel injectors are fi tted in the fuel rails.
The injector consists of a solenoid, core, needle valve and ho using. When a control signal from the ECM is applied to the
solenoid coil, the needle valve lifts up and fuel is injected under pressure into the intake port. The fuel sprays from the
injectors are directed onto the back of the intake valves.
The injection quantity is determined by the length of time that the ECM signal is applied to the solenoid coil.
The injectors installed in the fuel rails of supercharged engines are of a higher flow rating than those installed in normally
aspirated engines and are secured in position by spring clips. Seals are instal led between the injector mounts of the fuel
rails and the related re cesses in the charge air cooler adaptors.
Pressure Regulator

Pa
rts List
The pressure regulator is a diap hragm-operated valve that regula tes fuel-rail pressure at 3,0 bar above the intake manifold
pressure. A pipe connects the throttle induction elbow to the pressure regulator to provide the vacuum control signal. On
supercharged engines, the pressure regulator vacuum feed is taken from the top of the supercharger outlet duct.
The regulator is fitted between the rear end of the right-hand fuel rail (bank 1) and the fuel return line to the tank.
Circuit Diagram, Fuel Injection Syst em - Normally Aspirated Vehicles

Ite
m
Par
t
Number
De
scr
iption
1—F
u
el Return
2—F
u
el Pressure Regulator
3—Inta
k
e Manifold Pressure

Default mode Definitions

MECH
ANICAL LIMP-HOME MODE:

No el
ectronic throttle operation (mechanical
operation for last quarter of pedal travel)
M
aximum 25° throttle opening,
depending on adjustment of th rottle mechanical linkage
Engine
speed restricted to 3000
rpm maximum, by fuel cut-off
Hi
gh idle speed (1200 rpm approx.)
Misfire

at idle, due to cylinder cut as a means of control
ling idle speed (the misfire will switch cylinders, as the
strategy varies th e cylinder cut)
Cruise (speed) contr
ol inhibited
REVERSE THROTTLE PROGRESSION ENABLED:
El
ectronic throttle operation, limited to maximum 25°
Cruise (speed) contr

ol inhibited
• NOTE: The throttle oper ation uses the same map as for reverse gear.
ENGINE SPEED LIMIT:
Engine
runs normally, up to 3000 rpm
Engine

speed restricted to 3000
rpm maximum, by fuel cut-off
Cruise (speed) contr
ol inhibited
LIMP-HOME UNAVAILABLE:
Cruise (speed) contr
ol inhibited
R

everse throttle pr
ogression engaged at second occurrence of DTC flagging
Diagnostic Trouble Code (D
TC) index
DT
C
Cond
ition
P
ossible Causes
Acti
on
P0171Right-hand cylinders combustion too

leanAir
intake leak between MAF
sensor and throttle
F
uel filter system blockage
F

uel injector blockage
F

uel pressure regulator failure (low

fuel pressure)
Low f
uel pump output
H0

2S harness wiring fault
E

xhaust leak (before catalyst)
ECM receivi

ng incorrect signal from

one or more of the following
sensors - ECT, MAF, IAT, TP.
Fo
r intake system,
REFER to Section 303
-12
Intake Air

Distribu
tion and Filtering
.
F
or fuel filter,
REFER to Section 310
-01
Fuel Tank
and Lines.
Chec
k the fuel injectors. Check the
fuel pressure regu lator. Check fuel
pressure. For HO2S circuit tests,
REFER to Section 303
-14
Electronic
Engine

Controls
.
F
or exhaust information,
REFER to Section 309
-00
Exhaust
Sy

stem
.
For se
nsor circuit tests,
REFER to Section 303
-14
Electronic
Engine

Controls
.
P0172Right-hand cylinders combustion too

ri
ch
Engine
misfire
Bl

ocked air filter
F

uel system return blockage
Leak

ing fuel injector(s)
F

uel pressure regulator failure
(high fuel pressure)
ECM receivi
ng incorrect signal from

one or more of the following sensors - ECT, MAF, IAT, TP
Chec
k for 'engine misfire detected'
DTCs. Check the air filter element,
REFER to Section 303
-12
Intake Air

Distribu
tion and Filtering
.
Chec
k the fuel lines,
REFER to Section 310
-01
Fuel Tank
and Lines.
Chec
k the fuel injectors,
REFER to Fuel Injectors
- in t
his
section.
For fuel pressure regulator check,GO
to Pinpoint Test D.
.
Check the fuel
pressure,

REFE
R to Section 310
-00
Fu
el
Sy
ste
m
- General

Information
.
Check f o
r DTCs indicating a sensor
fault,
REFER to Section 303
-14 El
ectronic
Engine
C
ontrols
.
P0174
Left-hand cyl i
nders combustion too
lean
Air in
take leak between MAF
sensor and throttle
F u
el filter system blockage
F
u
el injector blockage
F
u
el pressure regulator failure (low

fuel pressure)
Low f u
el pump output
H0
2S harness wiri
ng fault
E
x
haust leak (before catalyst)
ECM receivi
n
g incorrect signal from

one or more of the following sensors - ECT, MAF, IAT, TP
F o
r air intake sy
stem information,
REFER to Section 303
-12 Int
ake Air

Distribu tion and Filterin
g
.
Check the fuel fi lter,
REF
ER to Section 310
-01
Fu
el Tank
and Lines.
Chec k the
fuel injectors,
REFER to Fuel Injectors
- in t h
is
section.
For fuel pressure regulator check,GO
to Pinpoint Test D.
. Ch
eck the fuel
pressure,
REFER to Section 310
-00 Fu
el
Sy
ste
m
- General

Information
.
Check f o
r DTCs indicating which HO2

sensor is faulty,
REFER to Section 303
-14 El
ectronic
Engine
C
ontrols
.
Check f o
r DTCs indicating a sensor
fault,
REFER to Section 303
-14 El
ectronic
Engine
C
ontrols
.
P0175Left-hand cyli

nders combustion too
rich
Engine m
isfire
Bl
ocked air
filter
F
u
el system return blockage
Leak
i
ng fuel injector(s)
F
u
el pressure regulator failure
(high fuel pressure)
ECM receivi n
g incorrect signal from

one or more of the following sensors - ECT, MAF, IAT, TP
Check for 'en
gine misfire detected'
DTCs. Check the air filter element,
REFER to Section 303
-12 Int
ake Air

Distribu tion and Filterin
g
.
Chec k the
fuel lines,
REFER to Section 310
-01 Fu
el Tank
and Lines.
Chec k the
fuel injectors,
REFER to Fuel Injector
- Vehicles Wi
thout: Supercharger
/

Fue
l Injector
- Ve
hicles With
:
Supercharger
in this
section.
For fuel pressure regulator check,GO
to Pinpoint Test D.
. Check for DT
Cs
indicating a sensor fault,
REFER to Section 303
-14 El
ectronic
Engine
C
ontrols
.
P0201F
u
el injector circuit malfunction, Cyl

1
Injector discon n
ected
Inject
or wir
ing open or short circuit

Injector fail
ure
F
o
r fuel injector circuit tests,GO to
Pinpoint Test A.
.
P0202Fu
el injector circuit malfunction, Cyl

3
P0203F u
el injector circuit malfunction, Cyl

5
P0204F u
el injector circuit malfunction, Cyl

7
P0205Fu
el injector circuit malfunction, Cyl

2
P0206Fu
el injector circuit malfunction, Cyl

4
P0207F u
el injector circuit malfunction, Cyl

6
P0208F u
el injector circuit malfunction, Cyl

8
P0300Ran d
om misfire detected
ECM t
o
ignition coil primary circuit
faults (cylinder misfire detected DTCs also logged)
Ignition coil ground circuit; open
ci
rcuit, high resistance
F
u
el injector circuit fault(s)
(injector DTCs also logged)
F o
r ignition circuit tests,
REFER to Section 303
-07 En
gine
Ignition.
F or engi
ne information,
REFER to Section 303
-00 En
gine
Sy
ste
m
- General

Information
.
F o
r fuel injector circuit tests,GO to

ci
rcuit includes the EMS fuse box,
fuse 05, and the fuel injection relay. For additional information,
refer to the wiring diagrams. CLEAR DTC. TEST the system for normal operation.
A4: CHECK
THE INJECTOR GROUND
CIRCUIT FOR HIGH RESISTANCE
Turn the ignition swi
tch to the OFF
position.
1
Di
sconnect the battery negative terminal.
2
D

isconnect the ECM electrical connector, (EM15, vehi
cles with AJ26 engine, EM84, vehicles with AJ27
engine).
3
Meas
ure the resistance between the relevant injector harness electrical connector (IJ03 to IJ10,
vehicles with AJ26 engine, PI07 to PI14, vehicles with AJ27 engine), pin 01 and the ECM electrical
connector, pins as follows -
Vehicles with AJ26 engine:
Cy
l 1 IJ03, pin 01 (BU) and EM15, pin 07
Cy

l 2 IJ07, pin 01 (BU) and EM15, pin 18
Cy

l 3 IJ04, pin 01 (BN) and EM15, pin 17
Cy

l 4 IJ08, pin 01 (BN) and EM15, pin 05
Cy

l 5 IJ05, pin 01 (BG) and EM15, pin 16
Cy

l 6 IJ09, pin 01 (BG) and EM15, pin 04
Cy

l 7 IJ06, pin 01 (BW) and EM15, pin 06
Cy

l 8 IJ10, pin 01 (BW) and EM15, pin 15
Vehicles with AJ27 engine:
Cy
l 1 PI07, pin 01 (B
G) and EM84, pin 02
Cy
l 2 PI11, pin 01 (BW) and EM84, pin 06
Cy

l 3 PI08, pin 01 (BO) and EM84, pin 21
Cy

l 4 PI12, pin 01 (BW) and EM84, pin 04
Cy

l 5 PI09, pin 01 (B
G) and EM84, pin 14
Cy
l 6 PI13, pin 01 (BO) and EM84, pin 03
Cy

l 7 PI10, pin 01 (BW) and EM84, pin 05
Cy

l 8 PI14, pin 01 (BR) and EM84, pin 13
4
Is th

e resistance greater than 5 ohms?
Yes REPAIR the circuit between the relevant injector harness electrical connector pin 01 and the engine
control module electrical connecto r. For additional information, refer to the wiring diagrams. CLEAR
the DTC. TEST the system for normal operation.
No GO to A5
.
A5: CHECK
THE INJECTOR GROUND CI
RCUIT FOR SHORT CIRCUIT TO BATTERY
R
econnect the battery negative terminal.
1
Meas

ure the voltage between the relevant injector harness electrical connector (IJ03 to IJ10, vehicles

with AJ26 engine, PI07 to PI14, vehicles with AJ27 engine), pin 01 and GROUND.
2
Is th
e voltage greater than 3 volts?
Yes REPAIR the short circuit. For addi tional information, refer to the wiring diagrams. CLEAR the DTC.
TEST the system for normal operation.
No GO to A6
.
A6: CHECK
THE INJECTOR GROUND CI
RCUIT FOR SHORT CIRCUIT TO GROUND
Meas
ure the resistance between the relevant injector harness electrical connector (IJ03 to IJ10,
vehicles with AJ26 engine, PI07 to PI14, vehicles with AJ27 engine), pin 01 and GROUND.
1
Is
the resistance less than 10,000 ohms?
Yes REPAIR the short circuit. For addi tional information, refer to the wiring diagrams. CLEAR the DTC.
TEST the system for normal operation.
No Contact dealer technical support for advice on possible ECM failure.
P
INPOINT TEST B : DTC P0460; FUEL
LEVEL SENSE SIGNAL PERFORMANCE
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
B1: CHECK

THE FUEL LEVEL SENSOR REFERENCE GROUND
Di

sconnect the fuel level sensor electrical connector, BT15.
1