fuel sensor JAGUAR X308 1998 2.G Repair Manual

The left-hand and right-hand do wnpipe assemblies feature:
Catalytic converter with palladium / rhodium coated elem ents. The elements are uncoated for markets with only
leaded fuel.
Retained to the exhaust manifold flange by four thread ed studs. Joint-to-joint sealing is with a gasket. Engine-mounted bracket providing downpipe mounting by two nuts to the torque converter housing and two bolts to
the downpipe.
Front Muffler Assembly
ItemPart NumberDescription
1—Downpipe catalytic converter
2—Upstream heated oxygen sensor
3—Downstream oxygen sensor (North American markets only)
4—Engine mounting bracket (LHS and RHS)

The upstream heated oxygen sensor is located at the catalytic converter inlet and detects the concentration of oxygen in the
raw exhaust gases; an internal heater reduces the warm up time of the sensor output.
An oxygen sensor (without heater) is located at the converter outlet.
The ECM receives input signals from the se nsors and varies the fuel injector duration (mixture) to provide optimum gas
emissions.
Circuit Diagram, O2 Sensors / ECM

Fuel Tank and Lines - Fuel Tank and Li
nes
Description an
d Operation

Fuel Tank

Parts List
The steel fuel tank is located inside the trunk and mounted across the vehicle behind the passenger compartment bulkhead.
The fuel tank is held in posi tion by two retaining straps fi tted to body-mounted brackets.
The fuel tank has an integral non-adjustable fill er pipe and integral breather and vapor pipework.
A single fuel pump is mounted inside the tank on vehicles with normally aspirated engines. For vehicles with supercharged
engines, two pumps are fitted in the tank. Fuel is drawn by the pump(s) from the fuel tank and supplied via the fuel lines
and 70 micron filter to the fuel rails.
The fuel lines run from front-to-rear down the vehicle's left-hand-side.
Ite
m
Part
Number
Descr
iption
1—Fu

el filler latch box
2—Pressure reli

ef pipe, ORVR
(shown) / tank breather pipe on non-ORVR systems
3—Tank grounding
cable
4—Evaporative flan
ge assembly
(ORVR type shown)
5—Trunk elec
trical harne
ss (part of)
6—Fue
l
level sensor
flange/connector
7—Fu
el tank retaining straps
8—F
u
el tank retaining stra
ps adjustable clamps
9—Fu
el tank retaining straps lower brackets
10—Tank vapor outlet pipe to un
derflo
or pipe quick-fit connector
11—F
u
el filler latch bo
x water drain pipe

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

Fuel Tank and Lines - Fuel Tank and Li
nes
D
iagn
osis and Testing
Sym
p
tom Chart
Sy
m
ptom Chart
Pinpoint test A: P1230
S
p
ecial Tool(s)

D
i
gital multimeter

Generi
c scan tool


F
u
el tank sender (sensor) unit wrench
18G 1001
Sy m
ptom
Possib
l
e Sources
Acti
o
n
D
T
C P1230 Fuel pump relay
malfunction
Re lay
failure
Harness fault
Connector loose or corroded
Connector pins(s) bent or tracking between connections
Ground failure
*
*
*
*
*
GO to Pinpoint

Test A
*
D
T
C P1646 Secondary fuel pump
relay malfunction
Re lay
failure
Harness fault
Connector loose or corroded
Connector pins(s) bent or tracking between connections
Ground failure
*
*
*
*
*
GO to Pinpoint

Test B

*
D
T
C P0460 Fuel level sensor circuit
malfunction
Worn
or damaged sensor tracks
Harness fault
Connector loose or corroded
Connector pin/s bent or tracking between connections
Fuel level sensor to instrument pack circui ts intermittent short
or open circuit or high resistance. Fuel level sensor failure
Instrument pack fault (inc orrect fuel level data)
*
*
*
*
*
*
*
GO to Pinpoint

Test C
*
P
INPOINT TES
T A : A: P1230
T
E
ST CONDITIONS
D
E
TAILS/RESULTS/ACTIONS
A1
: RETRIEV
E DTCS
•
NOTE
: Battery and or ECM disconnection prior to scanning wi
ll erase all data, ensure that the correct DTC is present.

Conne
ct the scan tool
1
Have the DTC(s) and fr

eeze
frame data been recorded?
Yes GO to C2
C2
: CHECK CONTINUITY FUEL SENSOR
W

ith connectors BT014 and BT015 disconnected check
the resistance between the fuel level sensor pins.
1
Is
the resistance >70 and <1000 OHM?
Yes GO to C3
No Renew the level sensor and test the system for normal
operation.
C3
: CHECK FOR SHORT TO GROUND

Fu
el Tank and Lines - Fuel Level Sensor
Remov
a
l and Installation
Removal

Ins
tallation

1.
WA
RNING: BEFORE PROCEEDING, IT IS ESSENTIAL THAT THE
WARNING NOTES GIVEN IN SECTIO N 100-00 (UNDER THE HEADING
'SAFETY PRECAUTIONS') ARE READ AND UNDERSTOOD.
Remove the battery. For additional information, refer to Section 414
-01
Battery, Mounting and Cables
.
2.
Drain
the fuel tank using a suitable suction pump/tanker. If the On-
board Refueling Vapour Recovery (ORVR) system is fitted, refer to
Section 310
-00 Fu
el System
- Gen
e
ral Information
.
3. Remov
e the trunk front liner. For additional information, refer to
Section 501
-05 Interior Trim
and Ornamentation
.

4. D
isconnect the harness co
nnections to the sensor.

5. U
sing special tool 18G 1001, remo
ve the sensor retaining ring.

6.
Remov
e the sensor assembly and discard the seal.
1. Fitting a new level sensor is the reverse of the removal procedure,
noting that a new seal must be fitted.

1.
If fitted, disconnect the
wiring to the accelerometer.
2. Disconnect the wiring to the fuel level sensor harness.

3.
Disc
onnect the wiring to
the fuel pump connector.
4. If fitted, disconnect the wi ring to the pressure sensor
connector.

14 . R
emove fuel filler
latch box drain pipe.
1. Cut and remove the ratche t strap securing the drain
pipe to the filler tube.
2. Disconnect the drain pipe from the fuel filler latch box.
3. Pull the drain pipe th rough the body grommet and
remove.

15 . Di
sconnect the vapo
ur outlet pipe.
Relea
se the quick-fit coupling .
Plu
g
the vapour pipes.

16 . D
isconnect the fuel filler la
tch box from the filler tube.
Open t
he fuel filler flap
and remove the filler cap.
1. Remove the spring ring se curing the fuel filler latch
box to the filler neck.
2. Pull the fuel filler latch box free of the filler tube.
17. Detach the tank retaining straps.
Tape or tie the two reta i
ning straps/brackets to the rear
scuttle to allow tank removal.

pipe.
3
. Tie the drain pipe to th
e filler tube using a ratchet
strap. Trim strap.

10
.
Reconnect the trunk harness connections.
1. If fitted, connect the wi ring to the accelerometer.
2. Connect the wiring to the fuel level sensor harness.
3. Connect the wiring to th e fuel pump connector.
4. If fitted, connect the wiring to the pressure sensor connector.

11
.
Reconnect the lefthand side trunk harness if it has been
necessary to move it for access. Route the harness behind both
the filler tube and breather or pressure relief pipe.
1. Fit the harness securing cl ip to the mounting bracket.
2. Connect the fuel flap lock actuator connector.
3. Connect the lefthand rear lamp harness connector.
4. If applicable, feed the side marker lamp harness through the access hole in the floor and reseat the
sealing grommet.
On
the underside of the vehicl
e, fit the side marker lamp
connector and fix the harness to the securing clips.

12
.
On the underside of the vehicle, fit the drain pipe to the
securing clip.
13. On the underside of the vehicle, reconnect the fuel feed and
return pipes.
R
emove the plugs from the tank
and fuel feed and return