1998 JAGUAR X308 Mass air flow

is
of the 'hot-wire' type (the resistan
ce of the wire varies as incoming air passing over it has a cooling effect)
provides f
eedback to the ECM to perm
it monitoring of mass air flow
is NO
T serviceable, necessitating its renewal should a fault occur
Mass Air Flo
w (MAF) Sensor
Location

DT
C
De
scription
Possib
le Source
Acti
on
P0101Mass ai

r flow (MAF) sensor
range/performance
Bl
ocked air filter
Air

intake leak
Engine

breather leak
Throttl

e control malfunction
MAF

sensor to ECM sensing circuit
high resistance
MAF
sensor to ECM sensing circuit
intermittent short circuit to ground
MAF
sensor supply circuit high
resistance
MAF
sensor failure
Chec
k the air filter element, check the

air intake system for leaks,
REFER to Section 303
-1
2 Intake Air
Distribu

tion and Filtering
.
Chec
k the engine breather system for
leaks,
REFER to Section 303
-08
Engine
Emissi

on Control
.
F
or throttle control circuit tests,GO to
Pinpoint Test T.
. Fo
r MAF sensor
circuit tests,GO to Pinpoint Test A.
.
P0102Mass ai
r flow (MAF) sensor sense
circuit low voltage
Bl
ocked air filter
MAF

sensor to ECM sensing circuit
high resistance or open circuit
MAF
sensor to ECM sensing circuit
intermittent short circuit to ground
MAF
sensor supply circuit open
circuit or short circuit to ground
MAF
sensor failure
Chec
k the air filter element,
REFER to Section 303
-1
2 Intake Air
Distribu

tion and Filtering
.
For MAF
sensor circuit tests, GO to
Pinpoint Test A.
.
P0103Mass ai
r flow (MAF) sensor sense
circuit high voltage
MAF
sensor to ECM reference
ground circuit open circuit
MAF
sensor to ECM sensing circuit
short circuit to high voltage
MAF sensor
failure

For MAF
sensor circuit tests,GO to
Pinpoint Test A.
.
P0106BARO ci
rcuit, low voltage
BARO f
ailure (internal ECM fault)
Contact deal
er technical support for
advice on possible ECM failure.
P0107BARO ci
rcuit, high voltage
BARO f
ailure (internal ECM fault)
Contact deal
er technical support for
advice on possible ECM failure.
P0111In
take air temperature (IAT)
sensor range/performance
Bl
ocked air filter
Air

intake leak
Engine

breather leak
IAT sensor to

ECM wiring open
circuit or high resistance
IAT se
nsor to ECM sensing circuit
short circuit to high voltage
IAT sensor fail
ure
Chec
k the air filter element, check the

air intake system for leaks,
REFER to Section 303
-1
2 Intake Air
Distribu

tion and Filtering
.
Chec
k the engine breather system for
leaks,
REFER to Section 303
-08
Engine
Emissi

on Control
.
F
or IAT sensor circuit tests,GO to
Pinpoint Test B.
.
P0112In
take air temperature (IAT)
sensor sense circuit high voltage
(low air temperature)
IAT sensor to
ECM wiring open
circuit or high resistance
IAT se
nsor to ECM sensing circuit
short circuit to high voltage
IAT sensor fail
ure
F
or IAT sensor circuit tests,GO to
Pinpoint Test B.
.
P0113In
take air temperature (IAT)
sensor sense circuit low voltage
(high air temperature)
IAT sensor to
ECM wiring short
circuit to ground
IAT sensor fail
ure
F
or IAT sensor circuit tests,GO to
Pinpoint Test B.
.
P0116E
ngine coolant temperature (ECT)
sensor range / performance
Low/contaminated coolant Therm
ostat failure
ECT se

nsor to ECM sensing circuit
high resistance when hot
ECT se
nsor to ECM sensing circuit
intermittent high resistance
ECT sensor
failure
Che
ck coolant level and condition.
Check thermostat function. For ECT
sensor circuit tests,GO to Pinpoint
Test C.
.
P0117E
ngine coolant temperature (ECT)
sensor sense circuit high voltage
(low coolant temperature)
ECT se
nsor disconnected
ECT se

nsor to ECM sensing circuit
high resistance, open circuit or
short circuit to high voltage
ECT sensor
failure
F
or ECT sensor circuit tests,GO to
Pinpoint Test C.
.
P0118E
ngine coolant temperature (ECT)
sensor sense circuit low voltage
(high coolant temperature)
Engine
overheat condition
ECT se

nsor to ECM wiring short
circuit to ground
ECT sensor
failure
Chec
k engine for overheating. For ECT

sensor circuit tests,GO to Pinpoint
Test C.
.
P0121Thro
ttle position (TP) sensor
circuit rang e/performance
TP sensor
to ECM wiring open
circuit or high resistance
TP se
nsor to ECM sensing circuits 1

or 2 short circuit to high voltage
TP sensor
failure
F
or TP sensor circ
uit tests,GO to
Pinpoint Test D.
, and G
O to Pinpoint
Test K.
.
D
iagnostic Trouble Code (DTC) Index

Pinpoint Tests
f
ailure
P1611Thr

ottle angle malfunction
TP sensor
circuit fault (refer to
P0121)
APP sensor circuit faul
t (refer to
P0121)
Throttl
e assembly failure
ECM failu

re
Se
e pinpoint tests for components
listed. For throttle body information,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
Contact deal
er technical support for
advice on possible ECM failure.
P1612Throttl
e offset malfunction
TP sensor
circuit fault (refer to
P0121)
APP sensor circuit faul
t (refer to
P0121)
Throttl
e assembly failure
ECM failu

re
Se
e pinpoint tests for components
listed. For throttle body information,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
Contact deal
er technical support for
advice on possible ECM failure.
P1637CAN AB
S/TCCM token missing
CAN
open circuit fault - ABS/TCCM
to ECM
CAN s
hort circuit fault
ABS/TCCM failu

re
ECM failu

re
F
or network circuit tests,
REFER to Section 418
-00
Module
Comm

unications Network
.
P1638CAN INST token missingCAN

open circuit fault - INST to
ECM
CAN s
hort circuit fault
INST

failure
ECM failu

re
F
or network circuit tests,
REFER to Section 418
-00
Module
Comm

unications Network
.
P1642CAN c

ircuit malfunction
CAN s
hort circuit fault
Control modul

e failure - check for
additional logged DTCs to locate
control module source
F
or network circuit tests,
REFER to Section 418
-00
Module
Comm

unications Network
.
P1643CAN TC

M token missing
CAN
open circuit fault - TCM to
ECM
CAN s
hort circuit fault
TCM failure


ECM failu

re
F
or network circuit tests,
REFER to Section 418
-00
Module
Comm

unications Network
.
P1646F

uel pump 2 relay malfunction.
NOTE: This DTC applies only to
the S/C fuel pump 2
F
uel pump 2 relay failure
F

uel pump 2 relay to ECM circuit
fault
F
uel pump 2 relay coil power
supply open circuit
ECM ground circuit faul
t (relay coil
drive)
F
or fuel pump 2 relay circuit tests,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
P

INPOINT TEST A : DTC P0101, P0102, P0103; MASS AIR FLOW (MAF) SENSOR
RANGE/PERFORMANCE, HIGH/LOW VOLTAGE
•
NOTE: Before commencing this
test, check the air filter for blockage, the engine air inta ke and breather systems for
leaks, and the TPS for additional DTCs.
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
A1: CHECK

THE MAF SENSOR SENS
E CIRCUIT FOR HIGH RESISTANCE
Di
sconnect the battery negative terminal.
1
D

isconnect the ECM electrical connector, EM12.
2
Di

sconnect the MAF sensor electrical connector, PI35.
3
Meas

ure the resistance between EM12, pin 13 (GY) and PI35, pin 02 (GY).
4
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. TEST the system for normal operation.
No GO to A2
.
A2: CHECK
THE MAF SENSOR SENSE CI
RCUIT FOR SHORT TO HIGH VOLTAGE
R
econnect the battery negative terminal.
1
Turn the ignition swi

tch to the ON
position.
2
M
easure the voltage between the MAF sensor electrical connector, PI35, pin 02 (GY) and GROUND.
3
Is th

e voltage greater than 3 volts?

Yes
R
EPAIR the short circuit. For addi
tional information, refer to the wiring diagrams. CLEAR the DTC.
TEST the system for normal operation.
No GO to A3
.
A3: CHECK THE MAF SENSO
R SENS
E CIRCUIT FOR SHORT TO GROUND
• NO
TE: The short to GROUND may be intermittent. Move the
wiring to attempt to reproduce the conditions under which
the DTC was logged, and visually inspect the harness for any signs of chafing, see "visual inspection chart".
Turn the ignition swit
ch to the OFF
position.
1
Measure t
he resistance between PI35, pin 02 (GY) 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.
TEST the system for normal operation.
No GO to A4
.
A4: CHEC K THE MA
F SENSOR SUPPLY CIRCUIT VOLTAGE
Re
conn
ect the ECM electrical connector, EM12.
1
Turn the ignition swi
t
ch to the ON
position.
2
Me
asure the voltage between the MAF sensor electrical connector, PI35, pin 01 (WU) and GROUND.
3
Is the vol
t
age greater than 10 volts?
Yes GO to A5
.
No
REP
AIR the circuit between the MAF sensor electric
al connector, PI35, pin 01 (WU) and BATTERY. This
circuit includes the EMS control rela y, fuse 12 of the EMS fuse board, and splices in the harness. For
additional information, refer to the wiring diagrams. CLEAR the DT C. TEST the system for normal
operation.
A5: CHECK THE MAF SENSO
R SUPPLY CIRCUIT FOR HIGH RESISTANCE
Di
sc
onnect the battery negative terminal.
1
Di
sc
onnect the EMS fuse board electrical connector, EM20.
2
Meas
ure t
he resistance between EM20,
pin 10 (WU) and PI35, pin 01 (WU).
3
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. TEST the system for normal operation.
No INSTALL a new MAF sensor.
REFER to Mass Air Flow (MAF) Sensor
in this
section.
CLEAR the DTC. TEST the system for normal operation.
P INPOINT TES
T B : DTC P0111, P0112, P0113;
INTAKE AIR TEMPERATURE (IAT) SENSOR
RANGE/PERFORMANCE, HIGH/LOW VOLTAGE
•
NOTE: Before commencing this
test, check the air filter for blockage and the engine air intake and breather systems for
leaks.
TE S
T
CONDITIONS
D E
TAILS/RESULTS/ACTIONS
B1: CHECK
THE IAT SENSOR
SENS
E CIRCUIT FOR HIGH RESISTANCE
Disc
onnect the battery negative terminal.
1
D
i
sconnect the ECM electrical connector, EM12.
2
Di
sc
onnect the MAF sensor electrical connector, PI35.
3
Me
asure
the resistance between EM12, pin 12 (UP) and PI35, pin 03 (UP).
4
Is th
e res
istance greater than 5 ohms?
Yes REPAIR the high resistance circui t. For additional information, refer to the wiring diagrams. CLEAR
the DTC. TEST the system for normal operation.
No GO to B2
.
B2: CHECK
THE IAT SENSOR SENSE CIRCUIT FOR SHORT TO HIGH VOLTAGE
R
e
connect the battery negative terminal.
1
Turn the ignition swi
t
ch to the ON
position.
2
Measure the voltage between PI 35,
pin 03 (UP) and GROUND.
3

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.
TEST the system for normal operation.
No GO to B3
.
B3: CHECK
THE IAT SENSOR SENS
E CIRCUIT FOR SHORT TO GROUND
Turn the ignition swi
tch to the OFF
position.
1
Meas
ure the resistance between PI35, pin 03 (UP) 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.
TEST the system for normal operation.
No INSTALL a new MAF sensor.
REFER to Mass Air Flow (MAF) Sensor

in this section.
CLEAR the DTC. TEST the system for normal operation.
PI
NPOINT TEST C : DTC P0116, P0117, P0118
; ENGINE COOLANT TEMPERATURE (ECT) SENSOR
RANGE/PERFORMANCE, HIGH/LOW VOLTAGE
•
NOTE: Before commencing this
test, check the coolant level and condition, check the operation of the thermostat, rectify
as necessary.
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
C1: CHECK THE ECT SEN

SOR SENS
E CIRCUIT FOR HIGH RESISTANCE
Di
sconnect the battery negative terminal.
1
D

isconnect the ECM electrical connector, EM11.
2
D

isconnect the ECT sensor electrical connector, PI04.
3
Meas

ure the resistance between EM11, pin 09 (UY) and PI04, pin 02 (UY).
4
Is th

e resistance greater than 5 ohms?
Yes
REPAIR the high resistance circui t. For additional information, refer to the wiring diagrams. CLEAR
the DTC. TEST the system for normal operation.
No GO to C2
.
C2: CHECK THE ECT SEN
SOR SENSE CI
RCUIT FOR SHORT TO HIGH VOLTAGE
R
econnect the battery negative terminal.
1
Turn the ignition swi

tch to the ON
position.
2
Meas
ure the voltage between PI04, pin 02 (UY) and GROUND.
3
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.
TEST the system for normal operation.
No GO to C3
.
C3: CHECK THE ECT SEN
SOR SENSE CIRCUIT FOR SHORT TO GROUND
Turn the ignition swi

tch to the OFF
position.
1
Meas
ure the resistance between PI04, pin 02 (UY) 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.
TEST the system for normal operation.
No INSTALL a new ECT sensor. REFER to Section 303
-0
3A Engine Cooling
/
30
3
-0
3B Supercharger
Coo

ling
. CLEA
R the DTC. TEST the sy
stem for normal operation.
P
INPOINT TEST D : DTC P0121, P0122,
P0123; THROTTLE POSITION (TP) SENSOR
RANGE/PERFORMANCE, HIGH/LOW VOLTAGE
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
D1: CHECK

THE TP SENSOR SENS
E CIRCUIT FOR HIGH RESISTANCE
Di
sconnect the battery negative terminal.
1

E
lectronic Engine Controls - Engine
Control Module (ECM) Adaptation
Gen
eral Procedures
When to car

ry out adaptations
DTCs P1000/P1111 Conditions for adaptation
Fuelling Adaptations Drive Cycle
•
NOTE: Make sure the engine is at normal operating
temperature. (75°C, 167°F) 1.
Whenever the battery is disconnected, the Engine Control
Module (ECM) adaptations are reset to a "green" ECM
condition. In this condition, certain functions of the ECM are
inhibited, and the ECM must "r elearn" these functions. To
enable the ECM to do this, the vehicle will have to perform
some maneuvres which it may, or may not, do during a normal
road test. The routine in this pr ocedure should be carried out at
Pre-Delivery Inspection, and after any emissions related
rectification work involving the disconnection of the battery.
2. When the DTCs relating to a rectified concern are cleared,
P1000 (system checks not complete since last memory clear)
will be flagged. This DTC does no t indicate a failure, just that
diagnostic drive cycles need to be performed. The vehicle's on-
board diagnostic system will confirm that all the diagnostic
drive cycles are complete by flagging P1111, (system checks
complete since last memory clear)
1. Make sure these conditions are checked and corrected, if
necessary, before carrying ou t the adaptation procedure.
MechanicalElectrical
Engi
ne oil level correct
Coo

lant level correct
F

uel level greater than
30%, less than 80%
F
uel filler cap correctly
fitted/secure, seal in good condition
Al
l rectification work
relating to DTCs completed
F
uel, ignition and cooling
systems in good order
Al
l Diagnostic Trouble
Codes (DTCs) cleared
Al
l rectification work
relating to DTCs completed
F
uses
Harnes

ses
E

lectrical connectors

1.
Either
the Jaguar approved diagnostic system (where
available), or a scan tool should be connected to measure the
Mass Air Flow rate. Most generi c scan tools should be capable
of reading this parameter.
Depending on road conditions and dealer location, it may be
difficult to achieve the road sp eeds necessary to reach the air
flow indicated. It is possible to reach these air flow figures by
inducing a load on the vehicle, (making use of hills, using a
lower gear ratio, etc) or, if no alternative is possible, by
restraining the vehicle and re aching the air flow figure
Si
te
Mass Air Flow
(gra
ms/second)
D
riving Conditions
1Up t

o 7 g/s
Idle
in
P for 2 minutes
21
0 to 14 g/s
O
pen throttle in
P for 2 minutes
31
8 to 22 g/s
O
pen throttle in
P or D with
guidance * for 2 minutes
42
5 to 30 g/s
D
rive with guidance * for 2
minutes

Diagnostic Monitor Comp
letion
stat
ionery in
D.
WARNING: This should not be attempted without the vehicle
being in a safe area and suitably chocked. Failure to follow this
instruction may result in personal injury.
Without using the Jaguar approved diagnostic system or a scan
tool with system readiness capability, it will not be possible to
confirm when the adaptations are complete, unless P1111,
(system checks complete since last memory clear) is flagged. If
such equipment is not available, ALL the diagnostic monitors
will have to run to enable DTC P1111 to be flagged. In some US
states, this code is a requirem ent for annual emissions tests.
1. The dri v
e cycles detailed here w
ill enable the monitors to run,
but only after fuelling adaptations are complete.
Entry C
onditions
Di
agno
stic
Engine

S p
eed
Ve
h
icle
Speed
Mass Air Flow
(gra ms/sec
ond)
Ti
m
e to
Completion
Catalyst Monitor1 100
to

1600 rpm
50 to
72

kph (31 to 45
mph)
5 to
30 g/s
23
se
conds
HO2S6
00 t
o
2500 rpm
29 to

113 kph
(18 to 70
mph)
4 to
16 g/s
F
u
el cut for
more than 10 seconds, but less than 30 seconds *
Catalyst Monitor SensorN/ AN/A10
to 90 g/s
14
0
seconds
F
u
el System
N/
AN/AMore than 6 g/s33 se
conds
AACVN/
A61 to

121 kph
(38 to 75
mph)
4 to
16 g/s
F
u
el cut for 2
seconds *
P /
N switch
1
800
to

2200 rpm
80 to

101 kph
(50 to 63
mph)
N/ A31 se
conds
Evaporative

em is
sions
N/
A48 to
89

kph (30 to 55
mph)
and idle
R e
fer to drive
cycles for leak
tests in this section
Re
fer to drive
cycles for leak
tests in this section
2. During the drive cycle, drive gent ly, avoiding hard acceleration,
braking or cornering and rough roads.
1. Drive at 84 to 97 kph (52 to 60 mph) for 40 seconds.
2. Accelerate to 113 kph (70 mph).
3. Close the throttle, (ideally at the start of a descent)
continue with closed throttle for 10 seconds. (* Fuel
cut)
4. Drive at 56 to 64 kph (35 to 40 mph), holding the throttle as steady as possib le, on a flat level road for
30 seconds minimum.

El
ectronic Engine Controls -
Mass Air Flow (MAF) Sensor
Remo
val and Installation
Remov
a
l
1.
Disc onne
ct battery ground cable (IMPORTANT, see SRO
86.15.19 for further information).

2. Disc
onnect connector from MAF sensor.

3. Re
move bolts securing MAF sensor to air cleaner.

4. Re
move air cleaner cover.
Re
lea
se clips.

5. Re
lease band clip - trunking to MAF sensor and remove
assembly.
Di sc
ard sensor seals