1998 JAGUAR X308 throttle

Driver Information
Chart
•

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: For definitions of Default Modes, see the foot of this table.
Poor
dr iveabilityEngine h e
sitates/poor
acceleration
Fue l
pump
Exhaus
t gas
recirculation
(EGR)
Air leakage Stop lamp swi t
ch
Throttl
e
sensors
Throttl
e
motor
Spark
plugs
fouled
Check f
o
r water ingress
into spark plug wells
Ignition coil fail
ure(s)
HT sh
o
rt to ground
(tracking) check rubber
boots for cracks/damage
ECM failu r
e
Check f
u
el pressure. For EGR information,
REFER to Section 303
-08 En gin
e Emission
Control.
F or i
ntake system information,
REFER to Section 303
-1 2
Intake Air Distribution

and F
ilt
ering
.
F or stop l
amp switch in
formation, refer to the
wiring diagrams. For throttle position sensor
tests,GO to Pinpoint Test D.
. Fo
r throttle motor
control circuit tests,GO to Pinpoint Test T.
. For
igni t
ion system,
REFER to Section 303
-07 En
gine Ignition
.
F or ECM
circuit tests,GO to Pinpoint Test
AD.
.
Engine backfiresFuel
pump
Air leakage MAF se

nsor
HO2 sensors
Spark plugs Check fo
r water ingress
into spark plug wells
HT sh o
rt to ground
(tracking) check rubber
boots for cracks/damage
Ignition coil fail
ure(s)
Chec
k fu
el pressure. For intake system
information,
REFER to Section 303
-12
Intake Air Distribution

and Filt
ering
.
F or MAF sensor ci
rcuit test
s,GO to Pinpoint Test
A.
. F or HO2 sensor
circui
t tests, check for DTC
indicating which sensor and follow indicated pinpoint test. For ignition system,
REFER to Section 303
-07 En
gine Ignition
.
Engine
s
urges
Air leakage
Fuel
pump
Stop lamp swit

ch
MAF s
e
nsor
Harness Throttl
e
sensors
Throttl
e
motor
Spark plugs
Check fo
r water ingress
into spark plug wells
HT sh o
rt to ground
(tracking) check rubber
boots for cracks/damage
ECM failu r
e
Fo
r
intake system,
REFER to Section 303
-1 2
Intake Air Distribution

and Filt
ering
.
Check fu
el pressure. For
stop lamp information,
refer to the wiring diagrams. For MAF sensor tests,GO to Pinpoint Test A.
. Fo
r throttle
position sensor tests,GO to Pinpoint Test D.
,
a n
dGO to Pinpoint Test
K.
. Fo
r throttle motor
circuit tests,GO to Pinpoint Test T.
. For ig
nition
system,
REFER to Section 303
-07 En
gine Ignition
.
F or ECM
circuit tests,GO to Pinpoint Test
AD.
.
Engine detonates/k
nocks
Fue
l
pump
HO2 sensors
Air leakage Blocked part-load breather
(s
ervice action S474)
Mass ai
r fl
ow (MAF) sensor
Chec
k fu
el pressure. Fo
r HO2 sensor circuit
tests, check for DTC indicating which sensor and
follow indicated pinpoint test. For intake system
information,
REFER to Section 303
-1 2
Intake Air Distribution

and Filt
ering
.
Check service action S474
. For MAF sensor
tests,GO to Pinpoint Test A.
.
No t
hrottle response
Traction contr
o
l invoked
Throttl
e
sensors
Throttl
e
motor
Fo
r th
rottle position sensor tests,GO to Pinpoint
Test D.
, andG O to Pinpoint
Test
K.
. Fo
r throttle

motor circuit tests,GO to Pinpoint Test T.
.
Cru i
se control inhibited or

disabled
Cru i
se control switch
Throttle

sensors
Stop lamp swit

ch
For cru
i
se control switches,
REFER to Section 310
-03
Speed Control
.
For th
rottle position sensor tests,GO to Pinpoint
Test D.
, andG O to Pinpoint
Test
K.
. For s t
op
light switch information, refer to the wiring diagrams.

Re
d
Engine
Failsafe
Mode
Lim
p-Home
P1224
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1229
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P01
22, P0123,
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P02
22, P0223
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P0121
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P11
22, P1123
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P12
22, P1223
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P11
21, P1632
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P12
51, P0560, P1658
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1631
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1611
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1633
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1609
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P05
06, P0507
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1656
Re

d
Engine
Failsafe
Mode
Engine
shut-down when combined with other
throttle failures
P1254
Re
d
Engine
Failsafe
Mode
Engine
shut-down when combined with other
throttle failures
P1250
Ambe
r
Engine
Failsafe
Mode
Cruis
e inhibited
P1516
Ambe

r
Engine
Failsafe
Mode
Cruis
e inhibited
P1517
Ambe

r
Engine
Failsafe
Mode
Cruis
e inhibited
P1571
Ambe

r
Engine
Failsafe
Mode
Cruis
e inhibited
P1696
Ambe

r
Engine
Failsafe
Mode
Cruis
e inhibited
P0568
Ambe

r
Engine
Failsafe
Mode
Cruis
e inhibited
P0570
Ambe

r
Engine
Failsafe
Mode
Cruis
e inhibited
P0569
Ambe

r
Engine
Failsafe
Mode
Cruis
e inhibited
P0567
Ambe

r
Engine
Failsafe
Mode
Cruis
e inhibited
P0566
Ambe

r
Engine
Failsafe
Mode
Cruis
e inhibited
P1697
Re

d
Re
stricted
Performance
Li
mp-Home unavailable. Reverse throttle
progression enabled
P05
60, P1254
Ambe

r
Re
stricted
Performance
Li
mp-Home unavailable. Reverse throttle
progression enabled. High idle speed
P12
50, P1254
Re

d
Re
stricted
Performance
Li
mp-Home unavailable. Reverse throttle
progression enabled
P1250
Ambe
r
Re
stricted
Performance
Engine
Speed Limit (runs normally, limited to

3000 rpm)
P01
16, P0117, P0118, P0125
Ambe

r
Re
stricted
Performance
Engine
Speed Limit (runs normally, limited to

3000 rpm)
P01
01, P0102, P0103, P0104
Ambe

r
Re
stricted
Engine
Speed Limit (runs normally, limited to
P03

00, P0301, P0302, P0303, P0304, P0305,
Warning
lightMess
age
De
fault Mode
DT
C

Default mode Definitions
MECHANIC
AL LIMP-HOME MODE:

No elec
tronic throttle operation (mechanical
operation for last quarter of pedal travel)
Ma
ximum 25° throttle opening,
depending on adjustment of th rottle mechanical linkage
Engine speed restri
cted to 3000
rpm maximum, by fuel cut-off
High i
dle speed (1200 rpm approx.)
Misfire
at idle, due
to cylinder cut as a means of control
ling idle speed (the misfire will switch cylinders, as the
strategy varies th e cylinder cut)
Cruise (speed) contr
o
l inhibited
REVERSE THROTTLE PROGRESSION ENABLED:
Elec
tronic throttle operation, limited to maximum 25°
Cruise (speed) contr
o
l inhibited
• NOTE: The throttle oper ation uses the same map as for reverse gear.
ENGINE SPEED LIMIT:
Engine runs
normally, up to 3000 rpm
Engine
speed restri
cted to 3000
rpm maximum, by fuel cut-off
Cruise (speed) contr o
l Inhibited
LIMP-HOME UNAVAILABLE:
Cruise (speed) contro
l inhibited
R
e
verse throttle pr
ogression engaged at second occurrence of DTC flagging
Diagnostic Trouble Code (D TC) Index
Performance3000
rpm)
P03
06,
P0307, P0308, P1313, P1314
Ambe
rRestri
cted
Performance
Engine
Speed Limit (runs normally, limited to

3000 rpm)
P03 27,
P0328, P0332, P0333, P1648
Ambe
rRestri
cted
Performance
R e
verse throttle pr
ogression enabled
P1474
AmberRestri
cted
Performance
Engine
Speed Limit (runs normally, limited to

3000 rpm)
P1230
Ambe rRestri
cted
Performance
Engine
Speed Limit (runs normally, limited to

3000 rpm)
P1671
Ambe rRestri
cted
Performance
Engine
Speed Limit (runs normally, limited to

3000 rpm)
P11 12,
P1113
Ambe
rRestri
cted
Performance
Gearbox defau l
t to 4th gear
P1601 (SC on
ly)
AmberRestri
cted
Performance
Gearbox defau l
t to 4th gear
P16
05 (
NA only)
Ambe
rRestri
cted
Performance
Gearbox defau l
t to 4th gear
P0702
Ambe
rRestri
cted
Performance
Gearbox defau l
t to 4th gear
P1795
Ambe
rRestri
cted
Performance
Gearbox defau l
t to 4th gear
P1796
Ambe
rRestri
cted
Performance
Gearbox defau l
t to 4th gear
P1797
Ambe
rRestri
cted
Performance
Gearbox defau l
t to 4th gear
P1605
Ambe
rNoneGearbox defau l
t to 4th gear
P0705 (SC on
ly)
Ambe
rNoneGearbox defau l
t to 4th gear
P0706
Ambe
rNoneGearbox defau l
t to 4th gear
P1720

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

P0122Throttle
position (TP) sensor 1 low
voltage
TP se ns
or to ECM sensing circuit 1
(TP sensor pin 3) open circuit or
high resistance
TP sensor fail
ure
F
o
r TP sensor circ
uit tests,GO to
Pinpoint Test D.
, and GO
to Pinpoint
Test K.
.
P0123Throttl e
position (TP) sensor 1
high voltage
TP se ns
or to ECM sensing circuit 1
(TP sensor pin 3) short circuit to
high voltage
TP sensor fail
ure
F
o
r TP sensor circ
uit tests,GO to
Pinpoint Test D.
, and GO
to Pinpoint
Test K.
.
P0125En
gine coolant temperature (ECT)
sensor response (for closed loop
fuel control)
Low/contaminated coolant Therm o
stat failure
ECT se
ns
or to ECM sensing circuit
high resistance, open circuit or
short circuit to high voltage
Che c
k coolant level and condition.
Check thermostat function. For ECT
sensor circuit tests,GO to Pinpoint
Test C.
.
P0131Right -
hand H02S sense circuit low
voltage
H02 S
disconnected
H0
2S to
ECM wiring open circuit
H0
2S short ci
rcuit to ground
H0
2S fail
ure
F
or R
ight-hand HO2S circuit tests,GO
to Pinpoint Test E.
.
P0132Right-
hand H02S sense circuit
high voltage
H02 S
sensing circuit short circuit to
high voltage
H0 2S groun
d braided shield open
circuit
H0 2S fail
ure
F
or R
ight-hand HO2S circuit tests,GO
to Pinpoint Test E.
.
P0133Right-
hand H02S sense circuit
slow response
Engine m
isfire
H02
S
disconnected
H0
2S mechanical damage

H0
2S to
ECM wiring intermittent
open circuit
H02 S
sensing circuit short circuit to
high voltage
H02S short ci
rcuit to ground
H02S groun

d braided shield open
circuit
H0 2S heater circuit faul
t
Exhaus
t leak

Low e
x
haust temperature
Injector fl
ow parti
ally blocked
Catal
y
st efficiency decrease
H0
2S fail
ure
Chec
k for 'en
gine misfire detected'
DTCs. For HO2S circuit tests,GO to
Pinpoint Test E.
.G
O to Pinpoint Test
F.
. Check for exhaust leaks,
REF
ER to Section 309
-00
Ex
haust
Sy
ste
m
.
Chec k inje
ctors,
REFER to Section 303
-04 Fu
el
Charging and Cont

rols
.
P0135Right
-
hand H02S heater circuit
malfunction
H02 S
disconnected
H0
2S h
eater power supply open
circuit
H0 2S heater to ECM wi
ring short
circuit or open circuit
H0 2S heater fai
lure
F
o
r right-hand HO2S heater circuit
tests,GO to Pinpoint Test F.
.
P0137Right-
hand catalyst monitor
sensor sense circuit low voltage
Catal y
st monitor sensor
disconnected
Catal y
st monitor sensor to ECM
wiring open circuit
Catal y
st monitor sensor short
circuit to ground
Cat a
lyst monitor sensor failure
F
or ri
ght-hand catalyst monitor sensor

circuit tests,GO to Pinpoint Test G.
.
P0138Right -
hand catalyst monitor
sensor sense circuit high voltage
Catal y
st monitor sensor sensing
circuit short circuit to high voltage
Catalyst
monitor sensor ground
braided shield open circuit
Cata
lyst monitor sensor failure
F
or ri
ght-hand catalyst monitor sensor

circuit tests,GO to Pinpoint Test G.
.
P0140Right -
hand catalyst monitor
sensor sense circuit no activity
Catal y
st monitor sensor
disconnected
Catal y
st monitor sensor
mechanical damage
Catal y
st monitor sensor to ECM
wiring open circuit
Catal y
st monitor sensor sensing
circuit short circuit to high voltage
Cataly
st monitor sensor short
circuit to ground
Catalyst
monitor sensor ground
braided shield open circuit
F or ri
ght-hand catalyst monitor sensor

circuit tests, GO to Pinpoint Test G.
.
Check f o
r exhaust leaks,
REFER to Section 309
-00 Ex
haust
Sy
ste
m
.
Chec k inje
ctors,
REFER to Section 303
-04 Fu
el
Charging and Con
t
rols
.

leak
/blockage
EVAP valve failure


P0444Evaporati

ve emissions system
(EVAP) valve circuit open circuit
EVAP t
o ECM drive circuit open
circuit or high resistance
EVAP failu
re
F
or evaporative emissions pinpoint
tests,
REFER to Section 303
-1
3 Evaporative

Emiss
ions
.
P0445Evaporati

ve emissions system
(EVAP) valve circuit short circuit
E
VAP to ECM drive circuit short
circuit to ground
EVAP failu
re
F
or evaporative emissions pinpoint
tests,
REFER to Section 303
-1
3 Evaporative

Emiss
ions
.
P0447Cani

ster close valve (CCV) circuit
open circuit
CCV to ECM
drive circuit open
circuit, high resi stance or short
circuit to ground
EVAP failu
re
F
or evaporative emissions pinpoint
tests,
REFER to Section 303
-1
3 Evaporative

Emiss
ions
.
P0448Cani

ster close valve (CCV) circuit
short circuit
CCV to
ECM drive circuit short
circuit to high voltage
CCV failure

F
or evaporative emissions pinpoint
tests,
REFER to Section 303
-1
3 Evaporative

Emiss
ions
.
P0452F

uel tank pressure (FTP) sensor
circuit low voltage
FTP
sensor disconnected
FTP

sensor to ECM sense circuit
open circuit or short circuit to
ground
FTP sen
sor to ECM power supply
circuit open circuit or short circuit
to ground
F
TP sensor failure
F
or evaporative emissions pinpoint
tests,
REFER to Section 303
-1
3 Evaporative

Emiss
ions
.
P0453F

uel tank pressure (FTP) sensor
circuit high voltage
FTP
sensor to ECM signal ground
circuit open circuit
F
TP sensor to ECM wiring (supply,
sense, signal, ground) short circuit
to each other
FTP
sensor to ECM sense circuit
short circuit to high voltage
F
TP sensor failure
F
or evaporative emissions pinpoint
tests,
REFER to Section 303
-1
3 Evaporative

Emiss
ions
.
P0460Fue

l level sense signal
performance
Fue
l level sensor
to instrument
cluster circuits in termittent short or
open circuit
F
uel level sensor failure
Instrument cluster
faul
t (incorrect
fuel level data)
F
or fuel level sensor
circuit tests,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
P0506Idl

e rpm lower than expected
Ai
r intake blockage
Acce

ssory drive overload
(defective/siezed component)
Thr
ottle valve stuck closed
Throttl

e assembly failure
Chec
k the air intake system.
REFER to Section 303
-1
2 Intake Air
Distribu

tion and Filtering
.
Check t
he accessory drive
components,
REFER to Section 303
-0
5 Accessory
Dr

ive
.
F
or throttle body information,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
P0507Idle rpm

higher than expected
Inta
ke air leak between MAF
sensor and throttle
Inta
ke air leak between throttle
and engine
Engine
breather leak
Cruis

e (speed) control vacuum
failure
Thr
ottle valve stuck open
Throttl

e assembly failure
Chec
k the air intake system.
REFER to Section 303
-1
2 Intake Air
Distribu

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

on Control
.
F
or cruise (speed) control information,


REFER to Section 310
-03
Speed
Control.
F
or throttle body information,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
P0560Vehicle voltage

malfunction
ECM battery
power supply open
circuit, high resistance
F
or ECM power supply circuit tests,
GO to Pinpoint Test AD.
.
P0566Cruise (speed) contr
ol
CANCEL
switch ON fault
Cru
ise (speed) control switches
internal steering wheel short circuit
to ground
For cru
ise (speed) control circuit tests,


REFER to Section 310
-03
Speed

P1122Acce
lerator pedal position (APP)
sensor circuit 'A' low voltage
A
PP sensor to ECM sense circuit
'A' (sensor pin 5) open circuit or
high resistance
Sensor power su
pply fault
APP s

ensor failure
For APP
sensor circuit tests,GO to
Pinpoint Test R.
, andG
O to Pinpoint
Test S.
.
P1123Acce
lerator pedal position (APP)
sensor circuit 'A' high voltage
A
PP sensor to ECM sense circuit
'A' (sensor pin 5) short circuit to
high voltage
APP s
ensor failure
For APP
sensor circuit tests, GO to
Pinpoint Test R.
, and G
O to Pinpoint
Test S.
.
P1221Acce
lerator pedal position (APP)
sensor circuit 'B'
range/performance
A
PP sensor to ECM sense circuit
'B' (sensor pin 3) open circuit,
short circuit or high resistance
Sensor power su
pply fault
Sensor r

eference ground fault
APP s

ensor failure
For APP
sensor circuit tests,GO to
Pinpoint Test R.
, andG
O to Pinpoint
Test S.
.
P1222Acce
lerator pedal position (APP)
sensor circuit 'B' low voltage
A
PP sensor to ECM sense circuit
'B' (sensor pin 3) open circuit or
high resistance
Sensor power su
pply fault
APP s

ensor failure
For APP
sensor circuit tests,GO to
Pinpoint Test R.
, andG
O to Pinpoint
Test S.
.
P1223Acce
lerator pedal position (APP)
sensor circuit 'B' high voltage
A
PP sensor to ECM sense circuit
'B' (sensor pin 3) short circuit to
high voltage
APP s
ensor failure
For APP
sensor circuit tests,GO to
Pinpoint Test R.
, andG
O to Pinpoint
Test S.
.
P1224Throttl
e control position error
Thro
ttle position adaptations not
performed after ba ttery disconnect
TP se
nsor disconnected
TP se

nsor to ECM sense circuits
open circuit, hi gh resistance
Throttl
e motor power relay failure
Throttl

e motor power relay to ECM
circuit fault
Throttl
e motor power relay power
supply open circuit
ECM ground circuit faul
t (relay coil
drive)
Th
rottle motor to ECM drive circuits

open circuit, short circuit, high
resistance
Throttl
e motor failure
Throttl

e assembly failure
Carry
out throttle adaptation
procedure. For TP sensor circuit
tests,GO to Pinpoint Test D.
, andG
O
to Pinpoint Test K.
. F
or throttle motor

circuit tests,GO to Pinpoint Test T.
.
F
or throttle body information,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
P1226Mechanica

l guard sensor
range/performance
Mechanica
l guard sensor to ECM
sense circuit open circuit, short
circuit or high resistance
Sensor power su
pply fault
Sensor r

eference ground fault
Mechanica

l guard sensor failure
Mechanica

l guard actuator
seized/spring broken
For mech
anical guard circuit tests,GO
to Pinpoint Test U.
. F
or sensor power
supply circuit tests,GO to Pinpoint
Test V.
. F
or sensor ground circuit
tests,GO to Pinpoint Test W.
. For
throttle body i
nformation,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
P1227Mechanica

l guard sensor circuit
low voltage
Mechanica
l guard sensor to ECM
sense circuit open circuit or high
resistance
Sensor power su
pply fault
Mechanica

l guard sensor failure
For mech
anical guard circuit tests,GO
to Pinpoint Test U.
. F
or sensor power
supply circuit tests,GO to Pinpoint
Test V.
. F
or throttle body
information,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
P1228Mechanica

l guard sensor circuit
high voltage
Mechanica
l guard sensor to ECM
sense circuit short circuit to high
voltage
Mechanica
l guard sensor failure
For mech
anical guard circuit tests,GO
to Pinpoint Test U.
. F
or throttle body
information,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.
P1229Throttl

e motor control circuit
mallfunction
Throttl
e motor disconnected
Th

rottle motor to ECM drive circuits

short circuit or open circuit
Throttl
e motor failure
Fo
r throttle motor circuit tests,GO to
Pinpoint Test T.
.
P1230Fue
l pump relay malfunction.
NOTE. This DTC covers the S/C
system fuel pump 1
F
uel pump relay failure
F

uel pump to ECM circuit fault
F

uel pump relay coil power supply
F
or fuel pump relay circuit tests,
REFER to Section 303
-04
Fuel
Charging and Con

trols
.

op
en circuit
ECM ground circuit faul
t (relay coil

drive)
P1235Vacuu m
switching valve (VSV) 1
circuit range/ performance
(mechanical guard position)
Vac u
um leak/blockage between the

throttle elbow and the throttle
vacuum actuator
Vacuu m
actuator failure
Mechanica
l
guard actuator
seized/spring broken
Carr y out mechanical checks
for
vacuum leak/blockag e, failed vacuum
actuator, and broken /siezed actuator
spring.
P1236Vacuu m
switching valve (VSV) 1
(vacuum) circuit failure
VSV 1 disconne cted

VSV 1 to ECM drive circu
i
t high
resistance, open circuit or short
circuit
VSV 1 powe r supply open
circuit
VSV 1 failu
r
e
For VSV tests,

REF
ER to Section 310
-03
Sp
eed
Control.
P1237Vacuu
m
switching valve (VSV) 2
(atmosphere) circuit failure
VSV 2 disconne cted

VSV 2 to ECM drive circu
i
t high
resistance, open circuit or short
circuit
VSV 2 power supply open
circuit
VSV 2 failu
r
e
For VSV tests,

REF
ER to Section 310
-03
Sp
eed
Control.
P1238Vacuu
m
switching valve (VSV) 3
(release) circuit failure
VSV 3 disconne cted

VSV 3 to ECM drive circu
i
t high
resistance, open circuit or short
circuit
VSV 3 powe r supply open
circuit
VSV 3 failu
r
e
For VSV tests,

REF
ER to Section 310
-03
Sp
eed
Control.
P1240Sensor r
e
fere
nce voltage
malfunction (throttle sensors, fuel
tank pressure se nsor) (ECM pins
EM10-21; EM11-8)
ECM t o
sensors reference voltage
short circuit to ground, short circuit
to high voltage, op en circuit, high
resistance
TP sensor , pedal position and
mechan
ical guard sensor(s), fuel
tank pressure sens or failure(s)
Fo
r sensor reference voltage circuit
tests,GO to Pinpoint Test V.
.
P1241Sensor re
ferenc
e voltage low
(throttle sensors, fuel tank
pressure sensor) (ECM pins EM10-
21; EM11-8)
ECM t o
sensors reference voltage
short circuit to ground
TP sensor , APP
and mechanical
guard sensor(s), fuel tank pressure
sensor failure(s)
F o
r sensor reference voltage circuit
tests,GO to Pinpoint Test V.
.
P1242Sensor re
ferenc
e voltage high
(throttle sensors, fuel tank
pressure sensor) (ECM pins EM10-
21; EM11-8)
ECM t o
sensors reference voltage
circuit open circuit, high resistance,
short circuit to high voltage
TP sensor , APP
and mechanical
guard sensor(s), fuel tank pressure
sensor failure(s)
F o
r sensor reference voltage circuit
tests,GO to Pinpoint Test V.
.
P1243Sensor re
ference ground
malfunction (throttle sensors, fuel
tank pressure sensor, ECT sensor,
IAT sensor, IAT sensor 2) (ECM
pins EM10-20; EM11-12)
ECM t o
sensors reference ground
circuit open circuit, high resistance
Throttle sensors, fuel
tank pressure

sensor, ECT sensor, IAT sensor,
IAT sensor 2 failures
F o
r sensor reference ground circuit
tests,GO to Pinpoint Test W.
.
P1245Engine crank signal low voltage Starter relay coi
l to ECM/BPM
circuit open circuit
For en gin
e crank circuit tests,GO to
Pinpoint Test X.
.
P1246Engine crank signal high voltage Starter relay coi
l to ECM/BPM
circuit short circuit to B+ voltage
B P
M failure
For en
gin
e crank circuit tests,GO to
Pinpoint Test X.
.
P1250Engine load
malfunction
Air in
take leak
Engine breath

er leak
TP sens

or circuit fault (DTC P0121)

Throttle
valve spring failure
Check air i
ntake system for leaks,
REFER to Section 303
-12
Intake Air
Distribution and Filterin

g
.
Check engi
ne breather system for
leaks,
REFER to Section 303
-08 En
gine
Emissi
on Control.
Se e
pinpoint test for P0121. For
throttle body information,
REFER to Section 303
-04 Fu
el
Charging and Con
t
rols
.
P1251Thr
o
ttle position malfunction
(engine off)
TP sensor to ECM wiri
ng open
circuit or high resistance
F o
r TP sensor circ
uit tests,GO to
Pinpoint Test D.
, andGO to Pinpoint