JAGUAR X308 1998 2.G Workshop Manual

s
ystem (pressure).
Outputs from the ECM control the radiator fans control module, located behind the left hand side of the bumper, to operate
the fans in the series mode (slow), paralle l mode (Fast) or Off modes. Hysteresis in the temperature and pressure switching
values prevents 'hun ting' between modes.
Under hot operating conditions, the fans may continue to operat e for some time after the engine has been switched off, but
will stop automatically when the coolant te mperature has been sufficiently reduced.
Engine Coolant Temperature Sensor (ECT) and ECM

The engine coolant temperature (ECT) sensor is located in the coolant outlet pipe and reacts to engine coolant temperature
changes, providing an input to the Engine Control Module (ECM). The sensor has a negative te mperature coefficient so that
the sensor resistance decrea ses as temperature rises.
Temperature / Resistance Relationship Graph

T
emperature / Resistance
Relationship Table

Engi
ne Coolant Temperature Sensor (ECT) - Circuit Diagram

Intercooler Pump Relay - Circuit Diagram
T emper
ature (°C)
No
mi
nal Resistance (kOHM)
-2
015 .0
4
05.7
4
202.45
401.15
600.
584
800.3
2
1000.
184
ItemPar
t
Number
De
scrip
tion
1—Eng
i
ne Coolant Temperature (ECT) Sensor
2—Eng
i
ne to EMS Harness Connector
3—EMS Con
trol Modu
le

ItemPar
t Number
De
scription
1—Lug

gage compartment fuse box
2—I

ntercooler pump relay
3—I

ntercooler pump
4—Electr

onic control module

Engine Cooling - Engine Cooling
Diagn
osis and Testing
Related Faults / Codes

Adaptive
Fue
ling
Sym
p
tom Chart
Sy
m
ptom Chart
S
p
ecial Tool(s)

D
i
gital multimeter

Generi
c scan tool
Conditi
on
Possib
l
e Source
Acti
o
n
D
T
C P0171 System too lean bank
1 (A)
D T
C P0174 System too lean bank
2 (B)
Fuel delivery blockage Fu
el delivery pressure (low)
F
a
ulty injector (blocked)
Ai
r i
ntake system leak
F
u
el injector electrical fault
ECT sensor
faul
t
MAFM sensor fault IAT se
nsor fault

Thro
tt
le position sensor
fault
Mec hanica
l check
Mec
hanica
l check
Mec
hanica
l check
Mec
hanica
l check
Go t
o DTC P020
1 to 0208
Go t
o
DTC P0116 to 0118, P0125
Go t
o
DTC P0101 to 0103, P1104
Go t
o DTC P011
1 to 0113
Go t
o
DTC P0121 to 0123, P0222,
P0223
D T
C P0172 System too rich bank
1 (A)
D T
C P0175 System too rich bank
2 (B)
F u
el delivery pressure
(high)
F a
ulty injector (leaking)
F
u
el injector continuously
open
Ai r i
ntake system restricted

Fu
el injector electrical fault
ECT sensor
faul
t
MAFM sensor fault IAT sensor fault


Thrott

le position sensor
fault
Mec hanica
l check
Mec
hanica
l check
Mec
hanica
l check
Mec
hanica
l check
Go t
o DTC P020
1 to P0208
Go t
o
DTC P0116 to P0118, P0125
Go t
o
DTC P0101 to P0103, P1104
Go t
o DTC P011
1 to P0113
Go t
o
DTC P0121 to P0123, P0222,
P0223
Sy m
ptom
Possib
l
e Sources
Acti
o
n
D
T
C P0116 ECT circuit range / performance problem
Thermostat
Coo
l
ant level / contamination
Sensor out of range
Harness open circuit
Connector loose or corroded
*
*
*
*
*
GO to Pinpoint

Test A

*
D
T
C P0125 Insufficient coolant temperature for closed
loop fuel control
Thermostat
Coo l
ant level / contamination
Sensor out of range
Harness open circuit
Connector loose or corroded
*
*
*
*
*
GO to Pinpoint

Test A

*
D
T
C P0117 ECT circuit low input
Sensor o
p
en circuit
Harness open circuit
Harness short
*
*
*
GO to Pinpoint

Test B

*

Pinpoint test
A: P0116, P0125
Connector
loose or corroded
*
D
TC P0118 ECT circuit high input
Sensor short
Harness open circui

t
Harness short
Connector loose or corroded
*
*
*
*
GO to Pinpoint

Test C
*
D
TC P1474 Intercooler coolant pump relay malfunction
Intercooler pump relay
failure
Intercooler pump relay to ECM drive circuit
fault Intercooler pump relay coil ground circuit
fault Harness fault
Connector loose or corroded
Connector pins(s) bent or tracking between
connections ECM power supply fault
*
*
*
*
*
*
*
GO to Pinpoint

Test D
*
P
INPOINT TEST A : P0116, P0125
T
EST CONDITIONS
D
ETAILS/RESULTS/ACTIONS
A1

: RETRIEVE DTCS
•

NOTE: Battery and or ECM disconnection prior to scanning wi
ll erase all data, ensure that the correct DTC is present.
Conne
ct the scan tool
1
Have the DTC(s) and fr

eeze
frame data been recorded?
Yes GO to A2
A2: ENGINE
COOLANT SYSTEM CHECK
•

NOTE: Do not use the instrument display, if th
e ECT has failed this will not operate correctly.
Chec
k engine temperature rise using a thermocouple or
similar device.
1
Engine
temperature increasing?
Yes GO to A3
No Check coolant level
Check coolant for contamination
Check/test thermostat

A3: CHECK ECT SE
NSOR RANGE
All
o
w the engine to achieve any noted temperature within

the specified range, refer to temperature / resistance
relationship table or graph
1
I g
nition switch to position 0
2
D
i
sconnect PI004
Re
ar
of top hose
3
Meas
ure t
he resistance between sensor pins 1 and 2.
4
Tem
p
erature / resistance relationship OK?
Yes GO to A4
No Remove sensor and check temperature / resistance
relationship for 3 different temperatures. Renew as
required and test the syst em for normal operation.
A4: CHECK
HARNESS
CONTINUITY

I
gnition switch to position 0
1
Di

sconnect EM011
Inside E

CM housing
2
Me

asure the resistance between EM011/009 and
PI004/002.
3
I
s the resistance < 0.5 OHM?
Yes GO to A5
No Inspect harness / connector EM011/009, PI004/002 and
PI001/005 for corrosion, damage , bent or pushed back
pins. Repair as necessary and test the system for normal
operation.
A5: CHECK
HARNESS CONTINUITY
•

NOTE: To avoid a spurious result, disconnect connectors PI042 and PI006 (electronic throttle body) and PI035 (MAF
meter).

Ig
nition switch to position 0
1
Di
sc
onnect EM010
Inside E
C
M housing
2
Me
asure
the resistance between EM011/012 and
PI004/001.
3
I s
the resistance < 0.5 OHM?
Yes GO to A6
No Inspect harness/connector EM011/012, PI004/001,
PI001/006 and splices EMS02 / PIS01 for corrosion,
damage, bent or pushed back pins and repair as required.
Test the system for normal operation.
A6: CHECK HARNESS
CONTINUITY
•
NOTE
: Do not reconnect electronic thro
ttle body connectors PI042 and PI006.

Pinpoint test
B: P0117
I
gnition switch to position 0
1
Di

sconnect EM010
Inside E

CM housing
2
Meas

ure the resistance between the ECM connector
EM010/020 and the ECT connector PI004/001.
3
I
s the resistance < 0.5 OHM?
Yes GO to A7
No Inspect harness / connector EM010/020, PI004/001,
PI001/006 and splices EMS02 / PIS01 for corrosion,
damage, bent or pushed back pins. Repair as necessary
and reconnect all connectors.
Test the system for normal operation.
A7
: END
Perform

appropriate service drive cycle and check for the
presence of DTC.
1
Has
the fault code cleared?
Yes STOP
No Contact Jaguar Service
P
INPOINT TEST B : P0117
T
EST CONDITIONS
D
ETAILS/RESULTS/ACTIONS
B1

: RETRIEVE DTCS
•

NOTE: Battery and or ECM disconnection prior to scanning wi
ll erase all data, ensure that the correct DTC is present.

Connect
the scan tool
1
Have the DTC(s) and fr
eeze f
rame data been recorded?
Yes GO to B2
B2: CHECK ECT SEN
S
OR OPEN CIRCUIT
Ig
nition switch to position 0
1
D
i
sconnect PI004
Re
ar
of top hose
2
Meas
ure t
he resistance between the ECT sensor pins 1
and 2.
3
Re si
stance > 30 kOHM?
Yes Renew sensor and proceed to B6
No GO to B3
B3: CHECK HARNESS
CONTINUITY