ECM JAGUAR X308 1998 2.G Repair Manual

The air cleaner assembl y
consists of a tw
o piece box containing the ai r filter, an airflow/temperature unit (MAF sensor) and
the air intake duct which connects to the top of the throttle assembly. The engine full load breather feeds into the intake
duct from the bank 1 camshaft cover. Two tuned stubs on the air intake duct reduce the intake noise level.
Temperature Sensor

A second intake air temperature sensor (IAT sensor 2) is fitted at the outlet of the bank 1 charge air cooler. The sensor
provides an input to the ECM.
Air Intake Asse mbly

Evaporative E
missions - Evaporative Emissions
Description an
d Operation

To reduce the emission of fuel vapour, th e fuel tank is vented to atmosphere through activated charcoal adsorption canister
(s) which collects the fuel droplets. The ch arcoal is periodically purged of fuel when the EVAP Canister Purge Valve opens
the vapour line between the canister(s) and the air intake induct ion elbow. This action allows manifold depression to draw
air through the canister atmospheric vent, taking up the deposited fuel from the charcoal adsorber and burning the resulting
fuel vapour in the engine.
The EVAP Canister Purge Valve is controlled by the engine management system ECM. Purging is carried out in accordance
with the engine management fu eling strategy (see below).
The fuel tank vapour outlet is via a removeable flange assemb ly on the top surface of the tank. The vapour storage canister
or canisters are fitted on the underside of the vehicle below the rear seats.
There are three variants of the evaporativ e system. All systems use the charcoal adsorber storage canisters and purge valve
and operate as described above. The specific features of each system are described below. The evaporative systems are
designated as :
sin g
le canister system
ru
nn
ing loss system
ru
nn
ing loss with On-board Re-fueling Vapour Recovery (ORVR) system
EVAP Canister Purge Valve

Ite
m
Par
t
Number
De
scr
iption
1—EVAP canister purge v
alve
2—Valve s
olenoid connector
3—Vapour outlet to indu
ction elbow
4—Vapour
inlet from canister(s)
5—Vacuum contro
l pi
pe from induction elbow
6—Vacuum contro
l pi
pe to vapour pressure control va
lve - applicable to single canister systems only
7—Vacuum
control connection to EVAP valve

The E
VAP canister purge valve controls th
e flow rate of fuel vapour drawn into the engine during the canister purge
operation. The valve is opened by a vacu um feed from the induction elbow : the vacu um feed is controlled by the integral
valve solenoid and is applied when the so lenoid is energised. The solenoid is pulsed on (energised) and off by a fixed
frequency (100Hz) variable pulse width control signal (pulse width modulation). By varying the pulse on to off time, the
ECM controls the duty cycle of the valve (time that the valve is open to time closed) and thus the vapour flow rate to the
engine.
With no ECM signal applied to the va lve solenoid, the valve remains closed.
Can
ister Purge Operation
The
following pre-conditions are ne
cessary for purging to commence :
aft
er battery disconnection/reconnection, engine
management adaptations must be re-instated.
engine has run for
at least 8 seconds.
engi

ne coolant temperature is not less than 70 °C.
engine

not running in the fuel
cut off condition (eg overrun).
t
he adaptive fuel correction
function has not registered a rich or lean failure
t
he evaporative emission leak test has not failed
no faults have been diagnosted in th
e rel
evant sensor and valve circuits -
Air Flow Meter (AFM), Engine Coolant
Temperature sensor, Evaporativ e Canister Purge valve and Canister Close Valve (CCV).
If these conditions have been satisfied, purging is started. If any failures are registered, purging is inhibited.
The canister(s) is purged during each driv e cycle at various rates in accordance with the prevailing engine conditions. The
engine management software st ores a map of engine speed (RPM) against engine load (grams of air inducted / rev). For
any given engine speed and load, a vapour purge rate is assigned (purge rate increases with engine speed and load).
The preset purge rates are base d on the assumption of a vapour concentratio n of 100%. The actual amount of vapour is
measured by the closed loop fueling system : the input of evaporative fuel into the engine causes the outputs from the
upstream oxygen sensors to change, the am ount of change providing a measure of the vapour concentration. This feedback
causes the original purge rate to be adju sted and also reduces the amount of fuel input via the injectors to maintain the
correct air to fuel ratio.
Engine speed/load mapping and the corresp onding purge rates are different for single canister, running loss and ORVR
evaporative systems.

The ru nning loss
system has the following features :
a
normall
y open pressure control valve is fi
tted at the lefthand side of the tank.
two charcoal
canisters are connected in series to reduce th
e concentration of fuel in vapour vented to atmosphere.
a t
ank pressure sensor and canister close
valve are fitted to allow the on-board di agnostic facility to test for leaks in
the fuel and evaporative system.
The pressure control valve allows continuo us venting of vapour to the charcoal canisters during normal running but prevents
fuel entering the vent line duri ng refueling. Fuel vapour from the tank passes through the valve to the lefthand canister and
a third pipe connects the valve to the fill er neck. When refueling, the difference in pressure betw een the tank interior and
the open filler neck causes the valve to cl ose, shutting off the vapour vent line. Wh en the fuel cap is replaced, the pressures
are equalised and the pressure control valve opens the vent line to the canisters.
The canister close valve is a solenoid operated device controlled by the ECM. The valve is normally open and is closed only
during the leak test sequence.
The fuel pressure sensor is fitted to th e evaporative loss flange and provides a volt age to the ECM which is proportional to
Ite
m
Par
t
Number
De
scr
iption
1—Vapour outl
et rol
lover valve
2—Evaporative flan
ge assembly
3—Tank vapour outlet pipe
4—Breather pipe
5—Pressure control
valve
6—Vapour pipe to canister
7—Charcoal cani
sters
8—Cani
st
er close valve
9—Vent pi
pe ai
r filter
10—Canister purge ou
tlet pipe
11—Vapour pipe conn
ecting canisters
12—EVAP canister purge v
a
lve
13—Vacuu
m
control signal from induction elbow
14—EVAP pu
rge valve outlet to induction elbow

Running Loss Sys
tem

The system has the
following features :
o
n
-board refueling vapour recovery (ORVR) to reduce the fu
el vapour vented directly to atmosphere from the filler
nozzle when refueling.
two ch arcoal
canisters are connected in series to reduce th
e concentration of fuel in vapour vented to atmosphere.
a t
ank pressure sensor and canister close
valve are fitted to allow the on-board di agnostic facility to test for leaks in
the fuel and evaporative system.
The canister close valve is a solenoid operated device controlled by the ECM. The valve is normally open and is closed only
during the leak test sequence.
The fuel pressure sensor is fitted to th e evaporative loss flange and provides a volt age to the ECM which is proportional to
tank vapour pressure.
Op era
tion of ORVR System
The ORVR system enabl
e
s fuel vapour generated during re-fueling to be collected by
the charcoal canisters. During normal
running of the vehicle, the vapour is collected and purged in the same way as for non-ORVR systems.
Ite
m
Par
t
Number
De
scr
iption
1—Grade vent
valve outl
et
2—Vapour outl
et from fil
l level vent valve (FLVV)
3—F
L
VV pressure relief valve outlet pipe
4—N
a
rrow diameter fuel filler tube
5—Charcoal can
i
sters
6—Cani
st
er close valve
7—Vent pi
pe ai
r filter
8—Vapour pipe
conn
ecting canisters
9—Canister purge ou
tlet pipe
10—EVAP canister purge v a
lve (engine bay)
11—Vacuu
m
control signal from induction elbow
12—EVAP pu
rge valve outlet to induction elbow

Running Loss with On-board R
efuelin
g Vapour Recovery (ORVR) System

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?