engine JAGUAR X308 1998 2.G Workshop Manual
[x] Cancel search | Manufacturer: JAGUAR, Model Year: 1998, Model line: X308, Model: JAGUAR X308 1998 2.GPages: 2490, PDF Size: 69.81 MB
Page 1182 of 2490

Ite
m
Par
t
Number
De
scr
iption
1—Engine
management fuse box
2—Engine
control module (E
CM)
Circuit Diagrams (extracts only)
ECM Su
pply Voltage
Page 1183 of 2490

It
em
De
scription
1Mechanica
l guard
position sensor (potentiometer)
2Pedal demand sensors (pot
entiometers)
3Thro
ttle position sensor
4Engine
control
module (ECM)
5Throttl
e motor power relay
6EMS fuse box
7Throttl
e motor
T
hrottle Sensors and Control
Page 1184 of 2490

Ite
m
Part
Number
Descr
iption
1—Knock
sensors, banks 1 and 2
2—Engine
control module (E
CM)
Knock
Sensor
Page 1185 of 2490

It
em
Par
t Number
De
scription
1—Cranksh
aft position sensor
2—Engine
control module (ECM)
Crankshaft Posi
tion sensor
Page 1186 of 2490

Ite
m
Par
t
Number
De
scr
iption
1—Camshaft position
sensor
2—Engine
control module (E
CM)
Cams
haft
Position sensor
Page 1187 of 2490

It
em
Par
t Number
De
scription
1—MAF
assembly
2—MAF s
ensor
3—IAT se
nsor
4—Engi
ne to vehicle harness connector
5—EMS fuse box
6—Engine
control module (ECM)
7—Charge air cool
er -
IAT sensor (superchar
ged engin
es only)
MAF
and IAT Sensors
Page 1188 of 2490

It e
m
De
scr
iption
1Engine
c
ontrol
module (ECM)
2Do
wnstream oxygen sensor (A)
3Upstream heated ox
ygen sensor
(A)
4D
o
wnstream oxygen sensor (B)
5Upstream heated ox
ygen sensor (B)
6Engine
management fuse box
Ox
yg
en Sensors
Page 1189 of 2490

E
lectronic Engine Controls -
Electronic Engine Controls
D
iagnosis and Testing
I
nspection and Verification
1.
1. Veri
fy the customer concern.
2. 2. Confirm which, if any, warning li ghts and/or messages were displayed on the instrument cluster.
• NOTE: If any warning lights and/or me ssages were displayed when the fault occurred, refer to the Driver Information
table for DTCs associated with the display, then to the DTC index table for possible sources and actions. Some warnings will
appear to clear when the ignition is cycl ed. This is often because the warning has flagged as a resu lt of one of the vehicle's
on-board diagnostic routines having run to detect the fault. If the same routine is not run when the ignition is switched ON,
the warning will not reflag until the routine does run. See the DTC summaries for drive cycle routines.
3. 3. Visually inspect for obvious signs of mechanical or electrical damage.
V
isual Inspection Chart
4.
4. Veri
fy the following syst
ems are working correctly:
Air in
take system
Coo
ling system
Charging system
F
uel charging system
5. 5. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding
to the next step.
6. 6. Where the Jaguar approved diagnostic sy stem is available, complete the S93 report before clearing any or all fault
codes from the vehicle.
• NOTE: If a DTC cannot be cleared, then there is a permanent fault present that flag s again as soon as it is cleared (the
exception to this is P1260, which will only clear following an ignition OFF/ON cycle after rectification).
7. 7. If the cause is not visually evident and the Jaguar approv ed diagnostic system is not available, use a fault code
reader to retrieve the fault codes be fore proceeding to the Diagnostic Trou ble Code (DTC) Index Chart, or the
Symptom Chart if no DTCs are set.
• NOTE: If the DTC flagged was not present for two or more co nsecutive cycles, it is classed as temporary, and will be
deleted following three cycl es during which no fault was present. This could result in a reported wa rning light/message with
no stored DTCs. If a fault is present for three consecutive cycles, the DTC becomes permanent, and will remain in the
module's memory for 40 drive cycles (a cy cle is an ignition ON/OFF, which will occur during the owner's normal use of the
vehicle. No action on the part of the technician is necessary to perform this cycle. A drive cycle is a series of conditions
needed to make the on-board diagnostic ro utine run, and may need a specific action on the part of the technician. See the
DTC summaries for driv e cycle routines).
8. 8. Using the Jaguar approved diagnostic system where available, and a scan tool where not, check the freeze frame
data for information on the conditions applicable when the fault was flagged. The format of this will vary,
dependin
g o
n the tool used, but can provide information useful to the technician in dia
gnos
in
g th
e fault.
MechanicalElectrical
Engi
ne oil level
Coo
ling system coolant
level
Fuel contamination
Throttle body Poly
-vee belt
F
uses
W
iring harness
E
lectrical connector(s)
Sens
or(s)
Engine
control module (ECM)
Tran
smission control module
Check spark plu
g type. Only re
sisted plugs should be fitted. Refer to specifications
section for gap
Relay date codes.
If the date on the rela
y is between R6 k1 and R6 k8, replace the
relay
Page 1190 of 2490

CAUTIO
N: When probing connectors to take
measurements in the course of the pinpoint tests, use the adaptor kit,
part number 3548-1358-00.
• NOTE: When performing electrical voltag e or resistance tests, always use a digital multimeter (DMM) accurate to 3
decimal places, and with an up-t o-date calibration certificate. When testing resistance, always take the resistance of the
DMM leads into account.
• NOTE: Check and rectify basic faults before beginning diagnostic ro utines involving pinpoint tests.
Sym
ptom Chart
Sym
ptom
(general)
S y
mptom (specific)
Possib
l
e source
Acti
o
n
No
n
-Start
Engine
does not cran
k
Starter relay ECM relay Batt
ery Park
/Neutral
switch
Starting system
Harness damage
Engine s
iezed
Check r
e
lay dates. Check
for DTCS. For starting
system,
REFER to Section 303
-06 Sta r
ting System
.
F or ECM
relay tests, GO to Pinpoint Test
AD.
.
F o
r battery information,
REFER to Section 414
-0 1
Battery, Mounting and
Cables.
Fo r
Park/Neutral tests, GO to Pinpoint Test AC.
. Fo
r engine information,
REFER to Section 303
-01 En
gine
.
Engine cranks, but does
not fireSecurity
syst
em /Immobiliser
engaged
Thr o
ttle contaminated
Harness damage
Fu
el pump relay
Fue
l
system
R
e
fer to service action
S491
Contact dealer techni
cal
support for information
on security system. For fuel system,
REFER to Section 303
-0 4
Fuel Charging and
Controls.
Check bull etins for throttl
e cleaning procedure.
Check service actions.
Engine cranks an d
fires,
but will not start
F u
el pump relay
Thr
o
ttle contaminated
Purge
val
ve
Fue
l
pump
Engine coolan
t
temperature
(ECT) sensor
Spark plugs
fouled
Ignition coil
fail
ure(s)
Check f
o
r water ingress
into spark plug wells
HT sh o
rt to ground
(tracking) check rubber
boots for cracks/damage
Cyli
nder compression loss
(short-term. Refer to bulletin; 303-52)
Re
fer to service action
S491
Fo
r fuel pump relay tests,
REFER to Section 303
-0 4
Fuel Charging and
Controls.
. Check bulletins for throttl
e cleaning procedure.
Check fuel pressure. Refe r to Technical service
bulletins. For ECT sensor tests, GO to Pinpoint Test C.
. Fo
r ignition system,
REFER to Section 303
-07 En
gine Ignition
.
Check bulletins an d service a
ctions.
Di
f
ficult to
start
D iff
icult to start cold
Roc
h
ester valve
Batt
ery Thro
ttle contaminated
Fue
l
pump
Engine coolan
t
temperature
(ECT) sensor
Purge val
ve
Cyl
i
nder compression loss
(short-term. Refer to bulletin; 303-52)
Blocked part-load breather (s
ervice action S474)
R
e
fer to service action
S491
For R
ochester valv
e test, GO to Pinpoint Test AE.
. Fo
r battery information,
REFER to Section 414
-0 1
Battery, Mounting and
Cables.
Check bull etins for throttl
e cleaning procedure.
Check fuel pressure. For ECT sensor circuit tests,
GO to Pinpoint Test C.
. F
or evaporative
emissions tests,
REFER to Section 303
-1 3
Evaporative
Emiss
i
ons
.
R e
fer to bulletins for co
mpression information,
and service actions for part-load breather procedure and compressions.
Diff
icult to start hot
Roc
h
ester valve
Purge
val
ve
Thr
o
ttle contaminated
F
or R
ochester valv
e test, GO to Pinpoint Test AE.
. F
or evaporative emissions tests,
REFER to Section 303
-1 3
Evaporative
Page 1191 of 2490

Fue
l pump
Engine coolan
t temperature
(ECT) sensor
Blocked part-load breather (
service action S474)
Injec
tor leak
Emiss
ions
.
Check bull
etins for throttle cleaning procedure.
Check fuel pressure. For ECT sensor circuit tests,
GO to Pinpoint Test C.
. Refer to Servi
ce action
S474 for part-load breather procedure. For
injector leak test, Refer to technical service bulletin 303-39.
D
ifficult to start after hot
soak (vehicle standing
after engine has reached operating temperature)
Roc
hester valve
Thr
ottle contaminated
Purge
valve
Fue
l pump
Engine coolan
t temperature
(ECT) sensor
Blocked part-load breather (
service action S474)
Injec
tor leak
Engine cranks too
fa
st/slow
Batt
ery
Starter relay Harness Cyl
inder compression loss
(NA short term only. Refer to technical service bulletin; 303-39)
R
efer to service action
S491
F
or battery information,
REFER to Section 414
-0
1 Battery, Mounting and
Cables.
F
or starting system.
REFER to Section 303
-06 Sta
rting System
.
R
efer to technical servic
e bulletins and service
actions.
Engine
stalls
Engine st
alls soon after
start
F
uel pump relay
ECM relay Thr
ottle contaminated
CMP/CKP sen
sor
synchronization malfunction
Harness Fue
l pump
MAF
sensor malfunction
Engine coolan
t temperature
(ECT) sensor
Fue
l lines
Air leakage
F
uel pressure regulator
Check r
elay dates. Chec
k for DTCs. For fuel
pump relay tests,
REFER to Section 303
-0
4 Fuel Charging and
Controls.
F
or ECM relay tests, GO to Pinpoint Test
AD.
.
Check bull
etins for throttle cleaning procedure.
For CMP sensor circuit test s, GO to Pinpoint Test
C.
, for
CKP sensor circuit tests, GO to Pinpoint
Test N.
. Check fuel
pressure. For MAF sensor
circuit tests, GO to Pinpoint Test A.
. For EC
T
sensor tests, GO to Pinpoint Test C.
. F
or fuel
system,
REFER to Section 303
-0
4 Fuel Charging and
Controls.
and
REF
ER to Section 310
-0
1 Fuel Tank and Lines
. F
or intake system information,
REFER to Section 303
-1
2 Intake Air Distribution
and F
iltering
.
Engine
stalls on overrun
Thr
ottle contaminated
ECM relay F
uel pump relay
CMP/CKP sen
sor
synchronization malfunction
Check bull
etins for throttle cleaning procedure.
Check relay dates. For ECM relay tests, GO to Pinpoint Test AD.
. F
or fuel pump relay tests,
REFER to Section 303
-0
4 Fuel Charging and
Controls.
F
or CMP sensor circuit test
s, GO to Pinpoint Test
O.
, for
CKP sensor circuit tests, GO to Pinpoint
Test N.
.
E
ngine stalls at steady
speed, with or without cruise enabled
Thr
ottle contaminated
ECM relay F
uel pump relay
CMP/CKP sen
sor
synchronization malfunction
Harness Blocked part-load breather
(
service action S474)
Check bull
etins for throttle cleaning procedure.
Check relay dates. For EC M relay circuit tests,GO
to Pinpoint Test AD.
. F
or fuel pump relay circuit
tests,
REFER to Section 303
-0
4 Fuel Charging and
Controls.
F
or CMP sensor circuit test
s,GO to Pinpoint Test
O.
, for
CKP sensor circuit tests,GO to Pinpoint
Test N.
. Che
ck service actions.
Engine st
alls when
maneuvering
ECM relay F
uel pump relay
CMP/CKP sen
sor
synchronization malfunction
Check r
elay dates. For EC
M relay circuit tests,GO
to Pinpoint Test AD.
. F
or fuel pump relay circuit
tests,
REFER to Section 303
-0
4 Fuel Charging and
Controls.
F
or CMP sensor circuit test
s,GO to Pinpoint Test
O.
, for
CKP sensor circuit tests,GO to Pinpoint
Test N.
.