1998 JAGUAR X308 engine ignition

Diagnostic Trouble Code (D
TC) Index
Pinpoint Tests
Fue
l lines
Harness damage


Throttl

e sensors
Throttl

e motor
Spark plugs

fouled
Ignition coil

failure(s)
HT sho

rt to ground (tracking) check
rubber boots for cracks/damage
Exhaus
t gas recirculation (EGR)
F
or air intake syst
em information,
REFER to Section 303
-12
Intake Air

Distribu
tion and Filtering
.
F
or fuel pressure
regulator tests,
REF
ER to Section 303
-04
Fuel
Charging and Con

trols
.
F
or fuel line information,
REFER to Section 310
-01
Fuel Tank

and Lines.
F
or throttle sensor
circuit tests,
REFER to Section 303
-14
Electronic
Engine

Controls
.
Fo
r throttle motor
circuit tests,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
For ign
ition system tests,
REFER to Section 303
-07
Engine
Ignition.
Inspe
ct EGR components, for circuit
tests, GO to Pinpoint Test A.
.
DT
C
De
scription
Possib
le Source
Acti
on
P0400Exhaus

t gas
recirculation (EGR) flow malfunction
EGR
valve connector pins high
resistance
EGR pipe/exhaust manifold leak EGR pipe block
ed
EGR val

ve stuck open/closed,
blocked
EGR
valve failure
Check the EGR pi
pe, valve and manifold for
leaks/blockages. Check the EGR valve function.
For EGR valve circuit tests,GO to Pinpoint Test A.
.
P0405Exhaus
t gas
recirculation (EGR) drive
circuits open circuit
EGR valve power supply circuit o
pen circuit
EGR valve t

o ECM drive circuit
pair - EGR pins 1/3, 4/6 open circuit, high resistance
EGR val
ve failure (stepper motor
open circuit)
F
or EGR valve circuit tests,GO to Pinpoint Test
A.
.
P0406Exhaus
t gas
recirculation (EGR) drive
circuits short circuit
EGR valve t
o ECM drive circuit
pair - EGR pins 1/3, 4/6 short
circuit to ground or high voltage
EGR val
ve failure (stepper motor
short circuit)
F
or EGR valve circuit tests,GO to Pinpoint Test
A.
.
P
INPOINT TEST A : DTC P0400, P0405; EGR VALV
E FLOW MALFUNCTION/DRIVE CIRCUITS OPEN
CIRCUIT
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
A1: CHECK

THE EMS POWER SU
PPLIES TO THE EGR VALVE
D
isconnect the EGR valve electrical connector, PI34.
1
Turn the ignition swi

tch to the ON
position.
2
Make sure the EMS re lay i
s energized.
Vehicles with AJ26 engine:
Me
asure the voltage between PI34, pins 02 and 05 (WP) and GROUND
Vehicles with AJ27 engine:
Me
asure the voltage between PI34, pins 02 and 05 (WU) and GROUND
3
Is th

e voltage at either pin less than 10 volts?
Yes

E
vaporative Emissions - Evaporative Emissions
D
iagnosis and Testing
Prelim

inary Inspection
1.
1. Vis
ually inspect for obvious signs of mechanical or electrical damage.
V
isual Inspection Chart
2.
2. If
an obvious cause for an observed or
reported concern is found, correct th e cause (if possible) before proceeding
to the next step.
3. 3. If the concern is not visually evident, verify the symptom and proceed with diagnosis, using the Jaguar approved
diagnostic system, where available.
4. 4. Where K-Line or Vacutec equipment is available, it should be used as an aid to diagnosis. The equipment must be
capable of testing to the 0.020 thou standard (2001 MY on).
Diagnostic Drive Cycles
Following th
e setting of a DTC, the appropriate repairs must
be carried out, and the normal operation of the system
checked. This will be done by performing a series of drive cycles which will enable the vehicle to operate the evaporative
emissions system as a function check. For details of the drive cycles,
REFER to Section 303
-1
4 Electronic Engine Controls
.
ECM adapt
ations.
Diagnostic Trouble Code
(D
TC) index/Symptom Chart
1.
1. Wh
ere 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).
2. 2. 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.
3. 3. 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,
depending on the tool used, but can pr ovide information useful to the technician in diagnosing the fault.
CAUTION: 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.
MechanicalElectrical
Engi
ne oil level
Coo

ling system coolant level
Fue

l level
Fuel contaminatio
n
/grade/quality
Throttle body Poly

-vee belt
F
uses
W

iring harness
E

lectrical connector(s)
Sens

or(s)
Engine

control module (ECM)

Driver Info
rmation
•

NOTE: Use this table to identify DTCs associated with the me
ssage center display, then refer to the DTC index for possible
sources and actions.
• NOTE: A trip is an ignition OFF, 30 seconds delay, ignition ON cycle, plus a minimum coolant temperature increase of 22°
C (40°F) after which the coolant temperat ure should reach a minimum 71°C (160°F)
Diagnostic Trouble C
ode (DTC) index
Sy
m
ptom
Possib
l
e Source
Acti
o
n
D
i
fficulty in filling
R
e
striction in the vapor line between the fuel tank and the
carbon canister outlet/atmospheric port
Check f or free f
low of air.
F
u
el smell
Adaptat
i
ons incomplete
Cani
st
er purge valve inoperative
Carry
o
ut the adaptations
procedure,
REFER to Section 303
-14 Ele c
tronic Engine Controls
.
Chec k cani
ster purge valve
operation.
M e
ssage center display

(see below)
Fue l
filler cap missing/not
tightened after refuelling
Check fu
el filler cap condition
and fitment.
Warning Li
ght
Mess
age Defaul
t Mode
DT
C
RedCheck Engine (after two
trip
s)
ECM de
fa
ult (canister purge inhibited, adaptive fuel
metering inhibited)
P0442,
P0444, P0445,
P0447, P0448.
Re dCheck Engine (after two
trip
s)
No
neP04 52,
P0453.
Di
agno
stic
Trouble Code
De scr
iption
Possib
l
e Source
Acti
o
n
P0442Sy
st
em leak detected
F
u
el tank filler cap seal defective
Sy
ste
m leak (c
anister damage,
pipework damage)
Cani st
er close valve leaking
F
u
el tank leak
Chec
k fi
ller cap,
system pipework,
fuel tank,GO to Pinpoint Test A.
.
F o
r fuel tank information,
REFER to Section 310
-01 Fu
el Tank

and Lines.
P0444Canist
er purge valve circuit
open circuit
Cani st
er purge valve to ECM
drive circuit; open circuit, high
resistance
Cani st
er purge valve failure
F
or purge
valve circuit tests,GO to
Pinpoint Test B.
.
P0445Canist
er purge valve circuit
short circuit
Cani st
er purge valve to ECM
drive circuit; short circuit to ground
Canist
er purge valve failure
(stuck closed)
F or purge
valve circuit tests,GO to
Pinpoint Test B.
.
P0447Canist
er close valve (CCV)
circuit open circuit.
CCV power su pply ci
rcuit; open
circuit, short circuit
CCV to ECM drive circuit;
open
circuit, high resistance, short circuit to B+ voltage
CCV failure
Fo
r CCV circuit tests,GO to Pinpoint

Test C.
.
P0448Canist
er Close Valve (CCV)
circuit short circuit
Cani st
er close valve to ECM drive

circuit; short circuit to ground
Cani st
er close valve failure
F
o
r CCV circuit tests,GO to Pinpoint

Test C.
.
P0452 Fu
el tank Pressure (FTP)
sensor circuit; low voltage (low pressure)
FTP sen
sor disconnected
FTP sen

sor to ECM sense circuit;
open circuit, short circuit to ground
FTP sens
or to ECM power supply
circuit open circuit, short circuit to ground
FT
P sensor failure
For FT
P se
nsor circuit tests,GO to
Pinpoint Test D.
.
P0453Fu
el tank Pressure (FTP)
sensor circuit; high voltage
(high pressure)
FTP sen
sor to ECM signal ground
circuit open circuit
F T
P sensor to ECM wiring
(supply, sense, signal ground),
short circuit to each other
FTP sen
sor to ECM sense circuit
short circuit to B+ voltage
For FT P se
nsor circuit tests,GO to
Pinpoint Test D.
.
FT
P sensor failure
Sym
ptom Chart

Pinpoint Tests
P
INPOINT TEST A : P0442; SYSTEM LEAK DETECTED
•
NOTE: For K-Line or Vacutec equipment connection, see bulletin 05.1-29, or Vacutec operating instructions
TE

ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
A

1: CHECK PIPEWORK, ETC FOR LEAKS
Carr

y out a visual inspection of all accessible pipes, connectors and components. Rectify any faults
noted.
1
U
sing K-line or Vacutec equipment, check the
joints/connections in the following order:
Fi
ller cap
Cani

ster purge valve
Underfl

oor purge line connectors
Carbon

canister connections and vapor hoses
Cani

ster close valve and it's atmospheric port (disconnect the air vent tube if necessary)
2
Was

a fault found?
Yes Rectify the fault as necessary. Re peat the K-line or Vacutec test. CLEAR the DTC. Carry out a full
Evaporative system monitor drive cycle. Recheck DT Cs. For additional information, see "diagnostic
drive cycles" above.
No GO to A2
.
A2: CHECK
THE CA
NISTER PURGE VALVE FOR FLOW
Ru
n the engine.
1
Make sure the canister purge

valve is operating.
2
Using a flowmeter

(or a small piece
of paper) at the CCV inlet tube, confirm flow through the canister
purge valve.
3
Is th
ere flow through the canister purge valve?
Yes Possible intermittent faul t with vapor hoses, O-ring seals. Carefully check condition of hoses and
seals. Replace any suspect seals. Repeat the K-line or Vacutec test. CLEAR the DTC. Carry out a full
Evaporative system monitor drive cycle. Recheck DT Cs. For additional information, see "diagnostic
drive cycles" above.
No INSTALL a new canister purge valve.
REFER to Evaporative Emission Canister Purge Valve
- in t
his section.
CLEAR the DTC. Carry out a full Evap orative system monitor drive cycle.
P
INPOINT TEST B : P0444, P0445; PURGE VALVE CIRCUIT OPEN/SHORT CIRCUIT
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
B1: CHECK

THE PURGE VALVE DRIV
E CIRCUIT FOR HIGH RESISTANCE
Turn the ignition swi
tch to the OFF
position.
1
Di
sconnect the battery negative terminal.
Vehicles with AJ26 engine:
Disc
onnect the ECM electrical connector, EM15
Di

sconnect the purge valve electrical connector, EM39
Meas

ure the resistance between EM15,
pin 03 (PN) and EM39, pin 02 (PN)
Vehicles with AJ27 engine:
Disc
onnect the ECM electrical connector, EM80
Di

sconnect the purge valve electrical connector, EM39
Meas

ure the resistance between EM80, pin 01 (UY) and EM39, pin 02 (UY)
2
Is th

e resistance greater than 5 ohms?
Yes REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the
DTC. Carry out a full Evaporative system monitor drive cycle. For additional information, see

"d
iagnostic drive cycles" above.
No GO to B2
.
B2: CHECK THE PURGE VALVE DR
IV
E CIRCUIT FOR SHORT TO GROUND
Re
connect the battery negative terminal.
1
Meas
ure t
he resistance between EM39, pin 02 (PN for vehicles with AJ26
engine, UY for vehicles with
AJ27 engine), and GROUND.
2
Is t
he resistance less than 10,000 ohms?
Yes REPAIR the short circuit. For addi tional information, refer to the wiring diagrams. CLEAR the DTC.
Carry out a full Evaporative system monitor drive cycle.
No INSTALL a new purge valve,
REFER to Evaporative Emission Canister Purge Valve
- in thi
s section.
CLEAR the DTC. Carry out a full Evaporative system monitor drive cycle. Recheck DTCs. For additional
information, see "diagnostic drive cycles" above. If the DTC is repeated, contact dealer technical
support for advice on possible ECM failure.
PI
NPOINT TEST C : P0447, P0448; CANISTER CLOSE VALVE CIRCUIT OPEN/SHORT CIRCUIT
TE
S
T
CONDITIONS
D E
TAILS/RESULTS/ACTIONS
C1
: CH
ECK THE CCV DRIVE CIRCUIT FOR HIGH RESISTANCE
Turn the ignition swi
t
ch to the
OFF position.
1
Disc
onnect the battery negative terminal.
Vehicles with AJ26 engine:
Disc onne
ct the ECM electrical connector, EM13
Di
sc
onnect the CCV electrical connector, CV01
Meas
ure t
he resistance between EM13, pi
n 04, (OK) and CV1, pin 02 (OK)
Vehicles with AJ27 engine:
Disc onne
ct the ECM electrical connector, EM80
Di
sc
onnect the CCV electrical connector, CV01
Meas
ure t
he resistance between EM80,
pin 02 (GU) and CV1, pin 02 (GU)
2
Is the res
istance greater than 5 ohms?
Yes REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the
DTC. Carry out a full Evaporative system monitor drive cycle. For additional information, see
"diagnostic drive cycles" above.
No GO to C2
.
C2: CH
ECK THE CCV DRIVE CIRCUI
T FOR SHORT CIRCUIT TO GROUND
Re
connect the battery negative terminal.
1
Meas
ure t
he resistance between CV01,
pin 02 (OK for vehicles with AJ26 engine, GU for vehicles with
AJ27 engine), and GROUND.
2
Is t
he resistance less than 10,000 ohms?
Yes REPAIR the short circuit. For addi tional information, refer to the wiring diagrams. CLEAR the DTC.
Carry out a full Evaporative system monitor drive cycle.
No INSTALL a new CCV. CLEAR the DTC. Carry out a fu ll Evaporative system monitor drive cycle.
Recheck DTCs. For additional inform ation, see "diagnostic drive cycles" above. If the DTC is repeated,
contact dealer technical support for advice on possible ECM failure.
P INPOINT TES
T D : P0452, P0453; FUEL TANK
PRESSURE (FTP) SENSOR LOW/HIGH VOLTAGE
TES
T
CONDITIONS
DE
TAILS/RESULTS/ACTIONS
D
1:
CHECK THE FTP SENSOR SENSE CIRCUIT FOR HIGH RESISTANCE
Turn the ignition swi
t
ch to the OFF
position.
1
Disc
onnect the battery negative terminal.
2

Vehicles with AJ26 en
gine:
D

isconnect the ECM electrical connector, EM11
Di

sconnect the FTP sensor electrical connector, FP01
Meas

ure the resistance between EM11,
pin 07 (RG) and FP01, pin 02 (RG)
Vehicles with AJ27 engine:
D
isconnect the ECM electrical connector, EM81
Di

sconnect the FTP sensor electrical connector, FP01
Meas

ure the resistance between EM81,
pin 16 (RG) and FP01, pin 02 (RG)
Is th
e resistance greater than 5 ohms?
Yes REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the
DTC. Carry out a full Evaporative system monitor drive cycle. For additional information, see
"diagnostic drive cycles" above.
No GO to D2
.
D2: CHECK
THE FTP SENSOR SENSE CI
RCUIT FOR SHORT CIRCUIT TO GROUND
R
econnect the battery negative terminal.
1
Meas

ure the resistance between
FP01, pin 07 (RG) and GROUND.
2
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.
Carry out a full Evaporative system monitor drive cycle.
No GO to D4
.
D3: CHECK
THE FTP SENSOR SENSE CIRCUI
T FOR SHORT CIRCUIT TO HIGH VOLTAGE
Turn the ignition swi
tch to the ON
position.
1
Measure the
voltage between FP
01, pin 02 (RG) 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.
Carry out a full Evaporative system monitor drive cycle.
No GO to D4
.
D
4: CHECK THE FTP SENSOR SIGNAL GROUND CIRCUIT FOR HIGH RESISTANCE
Di

sconnect the battery negative terminal.
Vehicles with AJ26 engine:
D
isconnect the ECM electrical connector, EM10
Meas

ure the resistance between EM11, pin 12 (BG) and FP01, pin 01 (BG)
Meas

ure the resistance between EM10, pin 20 (BG) and FP01, pin 01 (BG)
Vehicles with AJ27 engine:
Re
connect the ECM electrical connector, EM81
D

isconnect the ECM electrical connector, EM82
D

isconnect the ECM electrical connector, EM83
Meas

ure the resistance between EM82, pin 07 (BG) and FP01, pin 01 (BG)
Meas

ure the resistance between EM83, pin 13 (BG) and FP01, pin 01 (BG)
1
Is either resi

stance
greater than 5 ohms?
Yes REPAIR the high resistance circui t. This circuit includes harness splice, EMS02. For additional
information, refer to the wiring diagrams. CLEAR the DTC. Carry out a full Evaporative system
monitor drive cycle. For additional informat ion, see "diagnostic drive cycles" above.
No GO to D5
.
D5:
CHECK THE FTP SENSOR SIGNAL GROUND
CIRCUIT FOR SHORT CIRCUIT TO GROUND
R
econnect the battery negative terminal.
1
Meas

ure the resistance between
FP01, pin 01 (BG) and GROUND.
2
Is
the resistance less than 10,000 ohms?

Th
e engine management system provides optimum control of
the engine under all operating conditions using several
strategically placed sensors and any necessary actuators. Electronic engine control consists of:
engine
control module
throttle posi

tion sensor
engi

ne coolant temperature sensor
cam

shaft position sensor
c

rankshaft position sensor
mass air

flow sensor
intake air temper

ature sensor
kn

ock sensor
heat

ed oxygen sensor
Electronic Engine Control
Engine

Control Module (ECM)

The ECM incorporates a comprehensive monitoring and diagnostic capability including software variations to ensure system
compliance with the latest diagnostic and emissions legislation in different markets. The engine control module controls the
coil on plug ignition system, electronic fuel system, cr uise control and the electronic throttle control system.
The ECM responds to input signals received from sensors relating to engine operatin g conditions and provides output signals
to the appropriate actuators. These outp ut signals are based on the evaluated input signals which are compared with
calibrated data tables or maps held within th e ECM before the output signal is generated.
The ECM needs the following inputs to calibrate the engine properly:
cam
shaft position
It
em
Par
t Number
De
scription
1—Knock

sensor
2—Engine

coolant temperature sensor
3—Cranksh

aft position sensor
4—D

ownstream oxygen sensor
5—Upstream oxygen sensor
6—Camshaft position

sensor
P
arts List
engi

ne rpm
engi

ne coolant temperature
amount

of engine detonation

generates a signal when th
e dr
ive plate passes the sensor
sen
ds the ECM signals indicating crankshaft position and engine speed
is e

ssential for calculating spark timing
En

gine Coolant Temperature (ECT) Sensor
sen
ds the ECM a signal indicating the temperature of the engine coolant
is a t

emperature dependent resistor with a negative temperature coefficient (resistance changes inversely with
respect to temperature) and is constantly monitored by the ECM
Intake Air Temperature (IAT) Sensor

is m
ounted in the same housing as the MA
F sensor but is not a serviceable item
sen
ds the ECM a signal indicating the temperature of the air entering the engine
is a t

emperature dependent resistor which has a negative
temperature coefficient (its resistance changes inversely
with respect to ambient temperature).
Knock S
ensor (KS)
is a pi
ezo-electric device which sends a signal
to the ECM indicating engine detonation
Between 700 and 6800 rpm, the ECM will retard individual cylinder ignition timing when detonation occurs while allowing
the other cylinders to continue operating normally.
During acceleration, at critical load and speed conditions, the ECM retards ignition timing to prevent the onset of detonation.
H
eated Oxygen Sensor (HO2S)
are
positioned upstream of the catalytic convertor
is equipped with

a heating element wh
ich improves the response time of the sensors during engine warm-up
h
as the ability to generate a voltage signal proportional to the oxygen content of the exhaust gases leaving the
engine
pr
ovides feedback information to the ECM used to calc
ulate fuel delivery and provide optimum gas emissions
Variable V
alve Timing (VVT) Solenoid
R
efer to section 303-01.