1998 JAGUAR X308 service

W
ith EM010 and EM014 disconnected, measure the
resistance between EM014/004 and chassis ground EM008L.
1
I
s the resistance < 0.5 OHM?
Yes GO to H15
No Inspect harness / connector EM014 for corrosion, damage, or
pushed back pin.
Inspect ground stud EM008L for corrosion or damage.
Inspect harness / spli ce EMS36 for damage.
Repair as required an d reconnect plug(s).
GO to H14
H1
4: STOP
Perform

appropriate service drive cycle and check for the
presence of DTC.
1
Has
the fault code cleared?
Yes STOP
No Contact Jaguar Service
H
15: CHECK FOR O2 SENSOR CONTINUITY

M
easure the insulation resistance between EM012/016 and
EM012/022.
1
I
s the resistance > 10 MOHM?
Yes Reconnect all plugs.
GO to H21
No Inspect harness / connectors EM012, EM015 and EM024 for
corrosion, bent / pushed back pins.
Repair as required an d reconnect plug(s).
GO to H21
H2
1: END
Perform

appropriate service drive cycle and check for the
presence of DTC.
1
Has
the fault code cleared?
Yes STOP
No Contact Jaguar Service

Fuel System - General Inform
ation - Fuel System
Description an
d Operation

The fuel tank is mounted across the vehicle behind the passenger compartment bulkhead.
Fuel is drawn by the fuel pump from the tank and then supplied to the two fuel rails, via a filter.
Fuel injectors are installed in the fuel ra ils on each side of the intake manifold.
The amount of fuel injected into th e engine is controlled by the ECM.
A cross-over pipe connects the two fuel ra ils together at the front of the manifold.
A test valve in the cross-over pipe allo ws the fuel rail to be pressurized and de-pressurized during the servicing and
troubleshooting procedures.
A pressure regulator on the rear of the right fuel rail controls the pressure in the fuel rails.
A return line directs excess fuel from the pressure regulator back to the fuel tank.
Operation and service procedures
The fuel injector
s, rails, pres
sure regulator and, wher e fitted, supercharger are described in greater detail in Section 303-04
together with servicing procedures.
The fuel tank, pump, fuel level senders and fuel lines are similarly covered in Section 310-01.

Filler Cap and P
ipe
The fuel
filler cap with bayonet-type fixi
ng is located beneath a remote-release sp ring-latched lid on the rear saddle panel
on the left-hand-side of the vehicle.
Fuel Pum
p
The fu
el pump(s) is energized by an ECM co
ntrolled relay. Fuel is drawn by this pu mp and supplied to the fuel injectors via
the fuel line, filter and fuel rails.
Servicing of the fuel pump re quires fuel tank removal.
Ev
aporative Loss Flange Assembly
The evaporative-loss flan
ge asse
mbly is mounted centrally on top of the tank. The flange assembly consists of a removeable
steel cap which mounts the evaporative emissions system vapor outlet valves and, if applicable, a pressure sensor. The
external electrical supply to th e fuel pump(s) is also made via a connector on the flange.
The flange assembly is fixed to the tank by a locking ring which is turned usin g special tool JD-174. A seal is fitted between
the flange assembly and the tank. Three di fferent flange assemblies are applicable according to the evaporative emission
system fitted to the vehicle. The fl ange size and fixing are identical fo r the three systems, as described.
Removal of the evaporative flange assembly is necessary to gain access to th e fuel pump(s) and other internal components.
To remove the evaporative fl ange assembly the fuel tank must first be removed.
The evaporative flange variant assemblies are described, together with service information, in Section 303-13.
Fuel R
eturn
Excess fuel
is directed back to
the fuel tank via a return line.
Fuel Pum
p Relay
The
fuel pump relay,
under control of the ECM, switches power to the fuel pump motor.
I
nertia Fuel Shutoff (IFS) Switch
The IF
S switch is located in the right-hand
side footwell behind the footboard carpet . When activated the switch isolates the
ignition system and fuel pump, releases any locked doors and disables unnecessary electrical systems. The system can be
reset by pressing down the flexible cover on the top of the switch.
• NOTE: The doors will not unlock if the IFS switch is tripped when the ignition switch is in position '0'.

P a
rts List
The fuel level sensor is mounte d on the fuel tank vertical face and reacts to level changes via a float and pivot which is
connected to a potentiometer. As the fuel level drops the resistance increases.
The fuel level sensor can be serviced without removing the tank.
It e
m
Par
t
Number
De
scr
iption
1—Lockin
g rin
g
2—Fue
l
level sensor
3—Seal

Fuel
Level Sensor

Pinpoint test B:
P1646
W
i
th conditions as in A14, measure the insulation
resistance between EM013/001 and BT009/001.
1
I s
the resistance > 10M OHM?
Yes Reconnect all plugs and replace relay 4.
GO to A16
No
A 16:
END
Perform
a
ppropriate service drive cycle and check for the
presence of DTC.
1
Has th
e fault code cleared?
Yes STOP
No Contact Ja
guar Serv ice
PINPOINT TEST B : B: P1646
TE
ST CONDITIONS
D
E
TAILS/RESULTS/ACTIONS
B1
: RETRI
EVE DTCS
•
NOTE
: Battery and or ECM disconnection prior to scanning wi
ll erase all data, ensure that the correct DTC is present.

Pinpoint test C: P0460
Wi
th conditions as in B14, measure the insulation
resistance between EM013/009 and BT009/003.
1
I s
the resistance > 10M OHM?
Yes Reconnect all plugs and replace relay 1.
GO to B16
No
B 16:
END
Perform
a
ppropriate service drive cycle and check for the
presence of DTC.
1
Has th
e fault code cleared?
Yes STOP
No Contact Jaguar Service
PI
NPOINT TEST C : C: P0460
T
E
ST CONDITIONS
D
E
TAILS/RESULTS/ACTIONS
C1
: RETRIEVE DTC
S
•
NOTE
: Battery and or ECM disconnection prior to scanning wi
ll erase all data, ensure that the correct DTC is present.

W
ith connectors FC025, FC024, and BT014 disconnected
measure the resistance between FC025/013 and BT014.
1
I
s the resistance < 0.5 OHM?
Yes GO to C7
No Inspect harness / connectors / pins FC024, FC001/004,
BT004/025 and BT014 for corrosion, damage, bent or
pushed back pins. Repair as required and test the system
for normal operation.
C7
: END
Perform

appropriate service drive cycle and check for the
presence of DTC.
1
Has
the fault code cleared?
Yes STOP
No Contact Jaguar Service