1998 JAGUAR X308 ECM

Pinpoint test H: P0160
Me
asure the insulation resistance between EM012/016 and
EM015/001.
1
I s
the resistance > 10 MOHM?
Yes Reconnect all plugs.
GO to G20
No Inspect harness / EM012, EM 015 and EM024 for corrosion,
bent / pushed back pins . Repair as necessary.
GO to G20
G2 0: 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 H : P0160
T
E
ST CONDITIONS
D
E
TAILS/RESULTS/ACTIONS
H1
:
RETRIEVE DTCS
•
NOTE
: Battery and or ECM disconnection prior to scanning wi
ll erase all data, ensure that the correct DTC is present.

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'.

It
em
Par
t Number
De
scription
1—Fue

l level sensor
2—Instrument pack
3—CAN IN


4—J-

gate
5—Engine

management ECM


F
uel Level Sensor Circuit Diagram

Ite
m
Par
t
Number
De
scr
iption
1—Engine
m
anagement ECM
2—Boot fuse box

3—Fue
l
pump

Ci
rcui
t Diagram, Fuel Pump -
Normally Aspirated Vehicles

It
em
Par
t Number
De
scription
1—Engine

management ECM
2—Boot fuse box


3—Fue

l pumps


Ci
rcuit Diagram, Fuel Pump
- Supercharged Vehicles

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.

W
ith EM013 disconnected, measure the resistance
between EM013/001 and relay socket pin 1.
1
I
s the resistance < 0.5 OHM?
Yes GO to A9
No Inspect harness / connec tors EM013, EM003/005,
FC001/42, BT004/019 and BT011/010 for corrosion,
damage, bent or pushed back pins. Repair as required
and test the system for normal operation.
A9: CHECK
ECM GROUND CONTINUITY