ECM JAGUAR X308 1998 2.G Repair Manual
[x] Cancel search | Manufacturer: JAGUAR, Model Year: 1998, Model line: X308, Model: JAGUAR X308 1998 2.GPages: 2490, PDF Size: 69.81 MB
Page 1079 of 2490

F
or evaporative emissions components,
REFER to: Evaporative Emissions
(30
3-13
Evaporative Emissions, Diagnosis and Testing).
For ECT sensor tests,
REFER to: Electronic Engine Controls
(30
3-14
Electronic Engine Co ntrols, Diagnosis and
Testing).
Engine stalls
soon after start
F
uel pump relay
ECM relay
Harness damage Fue
l pump
Engine coolan
t temperature
(ECT) sensor
Fue
l lines
F
uel pressure regulator
Air leakage
Check f
or DTCS. For fuel pump and ECM relay
tests,
REFER to: Fuel Charging and Controls
(30
3-04
Fuel Charging and Controls, Diagnosis and Testing).
Check fuel pressure.
REFER to: Fuel System Pressure Check
(31
0-
00 Fuel System - Genera l Information, General
Procedures).
For ECT sensor tests,
REFER to: Electronic Engine Controls
(30
3-14
Electronic Engine Co ntrols, Diagnosis and
Testing).
For fuel line information,
REFER to: Fuel Tank and Lines
(31
0-01 Fuel
Tank and Lines, Description and Operation).
For fuel pressure regulator,
REFER to: Fuel Charging and Controls
(30
3-04
Fuel Charging and Controls, Diagnosis and Testing).
For intake system information,
REFER to: Intake Air Distribution and Filtering
(30
3-12 Intake Air Distribution and Filtering,
Description and Operation).
Engine hesi
tates/poor acceleration
Fue
l pump
Air leakage
F
uel pressure regulator
Fue
l lines
Harness damage Throttl
e sensors
Throttl
e motor
Spark
plugs fouled, gapped
incorrectly
Ignition coil
failure(s)
Check f
or water ingress into
spark plug wells
HT sho
rt to ground (tracking)
check rubber boots for cracks/damage
Exhaus
t gas recirculation (EGR)
(SC only)
Chec
k fuel pressure,
REFER to: Fuel System Pressure Check
(31
0-
00 Fuel System - Genera l Information, General
Procedures).
For intake system information,
REFER to: Intake Air Distribution and Filtering
(30
3-12 Intake Air Distribution and Filtering,
Description and Operation). For fuel pressure regulator,
REFER to: Fuel Charging and Controls
(30
3-04
Fuel Charging and Controls, Diagnosis and Testing).
For fuel lines information,
REFER to: Fuel Tank and Lines
(31
0-01 Fuel
Tank and Lines, Description and Operation).
For throttle position se nsor and throttle motor
relay tests,
REFER to: Electronic Engine Controls
(30
3-14
Electronic Engine Co ntrols, Diagnosis and
Testing).
For spark plug tests, GO to Pinpoint Test B.
.
For ign
ition system tests, GO to Pinpoint Test
A.
. F
or EGR information,
REFER to: Engine Emission Control
(30
3-08
Engine Emission Cont rol, Description and
Operation).
Engine ba
ckfires
Fue
l pump
Fue
l lines
Air leakage
Mass ai
r flow (MAF) sensor
Spark plugs
Check f
or water ingress into
spark plug wells
HT sho
rt to ground (tracking)
check rubber boots for cracks/damage
Chec
k fuel pressure,
REFER to: Fuel System Pressure Check
(31
0-
00 Fuel System - Genera l Information, General
Procedures).
For fuel pump and lines,
REFER to: Fuel Tank and Lines
(31
0-01 Fuel
Tank and Lines, Description and Operation).
For intake system,
REFER to: Intake Air Distribution and Filtering
(30
3-12 Intake Air Distribution and Filtering,
Description and Operation). For MAF sensor tests,
Page 1083 of 2490

Diagnostic Trouble Code (D
TC) index
D
iagnostic Trouble Code (DTC) Index
DT
C
De
scription
Possib
le Source
Acti
on
P0300Ran
dom misfire detected
ECM t
o ignition coil primary circuit
faults (cylinder misfire detected
DTCs also logged)
Ignition coil
ground circuit; open
circuit, high resistance
F
uel injector circuit fault(s)
(injector DTCs also logged)
Ignition coil
failure(s)
Check f
or water ingress into spark
plug wells
HT sho
rt to ground (tracking)
check rubber boots for
cracks/damage
Spark plug
failure/fouled/incorrect
gap
Cy
linder compression low
F
uel delivery pressure (low/high)
F
uel injectors restricted/leaking
Fuel contamination
P
AS pulley bolts loose (see Service
Actions)
W
orn camshaft/broken valve
springs
For ign
ition system tests,GO
to Pinpoint Test A.
. For
inje
ctor circuit tests,
REFER to: Fuel Charging and
Controls (30
3-04 Fuel
Charging and Controls,
Description and Operation).
Check compressions. For
spark plug tests,GO to
Pinpoint Test B.
.
Check fuel
pressure,
REFER to: Fuel System
Pressure Check (31
0-00 Fuel
System - General
Information, General
Procedures).
For fuel injectors,
REFER to: Fuel Charging and
Controls (30
3-04 Fuel
Charging and Controls,
Diagnosis and Testing).
For fuel tank and lines
information,
REFER to: Fuel Tank and
Lin
es
(310-01 Fuel Tank and
Lines, Description and
Operation).
Check PAS pulley bolt torque
(REFER to technical service
bulletins). For engine
information,
REFER to: Specifications
(3
03-01 Engine,
Specifications).
P0301Misfire
detected, Cyl 1
R
EFER to possible sources for P0300
R
EFER to actions for P0300.
P0302Misfire
detected, Cyl 3
P0303Misfire
detected, Cyl 5
P0304Misfire
detected, Cyl 7
P0305Misfire
detected, Cyl 2
P0306Misfire
detected, Cyl 4
P0307Misfire
detected, Cyl 6
P0308Misfire
detected, Cyl 8
P0351Igni
tion coil primary/secondary circuit
malfunction, cyl 1
ECM to
ignition module primary
circuit open circuit, short circuit to
ground, high resistance
Igni
tion module to ignition coil
primary circuit open circuit, short
circuit to ground, high resistance
Ignition modu
le ground circuit
open circuit, hi gh resistance
Ignition coil
failure
Ignition modul
e failure
F
or ignition circuit tests,GO to
Pinpoint Test A.
.
P0352Igni
tion coil primary/secondary circuit
malfunction, cyl 3
P0353Igni
tion coil primary/secondary circuit
malfunction, cyl 5
P0354Igni
tion coil primary/secondary circuit
malfunction, cyl 7
P0355Igni
tion coil primary/secondary circuit
malfunction, cyl 2
P0356Igni
tion coil primary/secondary circuit
malfunction, cyl 4
P0357Igni
tion coil primary/secondary circuit
malfunction, cyl 6
P0358Igni
tion coil primary/secondary circuit
malfunction, cyl 8
P1313Misfire rate
catalyst damage, Right-hand
cylinders. NOTE. This DTC will flag only
when accompanied by a random or
individual cylinder misfire DTC; P0300,
R
efer to possible causes for P0300-P0308
R
efer to actions for P0300-
P0308.
Page 1084 of 2490

Pinpoint Tests
P0301 t
o P0304
P1314M
i
sfire rate catalyst damage, Left-hand
cylinders. NOTE. This DTC will flag only
when accompanied by a random or
individual cylinder misfire DTC; P0300 to
P0308
P1316M i
sfire excess emission. NOTE. This DTC
will flag only when accompanied by an
individual cylinder misfire DTC; P0300 to
P0308
P1367Ignit i
on monitor (ignition module 1)
Ignition modu
le
1 disconnected
Ignition modul e
1 to ECM circuits
open circuit, short circuit to ground
or short circuit to B+ voltage
Ignition modul e
1 ground circuit
fault
Ignition coil relay fai
lure
Ignition coil open/short
circuit
Ignition module
1 failure
F
o
r ignition circuit tests,GO to
Pinpoint Test A.
.
P1368Igniti
on monitor (ignition module 2)
Ignition modu
le
2 disconnected
Ignition modul e
2 to ECM circuits
open circuit, short circuit to ground
or short circuit to B+ voltage
Ignition modul e
2 ground circuit
fault
Ignition coil relay fai
lure
Ignition coil
open/short
circuit
Ignition modul
e
2 failure
F
o
r ignition circuit tests,GO to
Pinpoint Test A.
.
PINPOINT TES
T A : DTC P0300, P0351, P0352, P0353, P0354, P0355, P0356, P0357, P0358;
RANDOM MISFIRE DETECTED, COIL PRIMARY/SECONDARY CIRCUIT MALFUNCTION
• NO
TE: Unless multiple cylinder misfires are apparent, only on
e circuit will normally need to be tested. The DTC set will
indicate which cylinder is misfiring.
TE S
T
CONDITIONS
D E
TAILS/RESULTS/ACTIONS
A1
: CH
ECK COIL FUNCTI
ON BY SUBSTITUTION
Swap the suspect coi l
for a known good unit.
1
CLEAR t
h
e DTC. TEST the syst
em for normal operation.
2
Do
es the same DTC reoccur? The DTC will indicate if the same cylinder is misfiring.
Yes GO to A2
.
No
INST
ALL a new coil.
REFER to: Ignition Coil
-On-Plug
LH
(30
3-07 Engine Ignition, Removal and Installation) /
Ignition Coil
-On-Plu g
RH
(30
3-07 Engine Ignition, Removal and Installation).
CLEAR the DTC. TEST the system for normal operation.
A2: CHECK THE IGNIT
ION COIL SUPPLY VOLTAGE
Disc
onne
ct the relevant ignition
coil electrical connector(s).
1
Turn the ignition swit
ch to the ON
position.
2
Measure the voltage between:
Cyl 1 PI18, pin
1 (PW) and GROUND
Cy
l 2 PI22, pin
1 (PW) and GROUND
Cy
l 3 PI19, pin
1 (PW) and GROUND
Cy
l 4 PI23, pin
1 (PW) and GROUND
Cy
l 5 PI20, pin
1 (PW) and GROUND
Cy
l 6 PI24, pin
1 (PW) and GROUND
Cy
l 7 PI21, pin
1 (PW) and GROUND
Cy
l 8 PI25, pin
1 (PW) and GROUND
3
Is
t
he voltage less than 10.5 volts?
Yes REPAIR the relevant ignition coil su pply voltage circuit. This circuit includes the ignition coil relay and
ignition modules. For additional information, refer to the wiring diagrams. CLEAR the DTCs. TEST the
Page 1085 of 2490

system fo
r normal operation.
No GO to A3
.
A3
: CHECK THE IGNITION COIL GROUND CIRCUIT FOR HIGH RESISTANCE
Turn the ignition swi
tch to the OFF
position.
1
Disc
onnect the relevant ignition module
electrical connector(s), EM27 and EM29.
2
Meas
ure the resistance between:
Cy
l 1 PI18, pin 2 (GU) and EM27, pin 08 (GU)
Cy
l 2 PI22, pin 2 (GB) and EM29 pin 08 (GB)
Cy
l 3 PI19, pin 2 (GR) and EM29, pin 11 (GR)
Cy
l 4 PI23, pin 2 (GS)
and EM27, pin 07 (GS)
Cy
l 5 PI20, pin 2 (GO) and EM29, pin 07 (GO)
Cy
l 6 PI24, pin 2 (GK) and EM27, pin 12 (GK)
Cy
l 7 PI21, pin 2 (GW) and EM27, pin 11 (GW)
Cy
l 8 PI25, pin 2 (GP) an
d EM29, pin 12 (GP)
3
Is th
e resistance greater than 5 ohms?
Yes REPAIR the high resistance circui t. This circuit includes in-line connector, PI01. For additional
information, refer to the wiring diagrams. CLEAR the DTCs. TEST the system for normal operation.
No GO to A4
.
A4:
CHECK THE POWER SUPPLIES TO THE IGNITION MODULES
Turn the ignition swi
tch to the ON
position.
1
Meas
ure the voltage between EM27, pin 10 (PW) and GROUND.
2
Meas
ure the voltage between EM29, pin 10 (PW) and GROUND.
3
Are both
voltages greater than 10 volts?
Yes GO to A5
.
No
REPAIR the circuit between EM27, pin 10 (PW) and/or EM29, pin 10 (PW). This circuit includes the
ignition coil relay, and the harness splice, EMS22. For additional information, refer to the wiring
diagrams.
A5:
CHECK THE GROUNDS TO THE IGNITION MODULES
Turn the ignition swi
tch to the OFF
position.
1
Meas
ure the resistance between EM27, pin 09 (B) and GROUND.
2
Meas
ure the resistance between EM27, pin 09 (B) and GROUND.
3
Is either resi
stance
greater than 5 ohms?
Yes REPAIR the high resistance circui t. This circuit includes the harness splice, EMS04. For additional
information, refer to the wiring diagrams. CLEAR the DTCs. TEST the system for normal operation.
No GO to A6
.
A6: CHECK
THE CIRCUIT BETWEEN THE IGNITION
MODULES AND THE ECM FOR HIGH RESISTANCE
Di
sconnect the battery negative terminal.
1
D
isconnect the ECM electrical connector, EM13.
2
Meas
ure the resistance between the following:
Cy
l 1 EM27, pin 02 (LGU) and EM13, pin 26 (LGU)
Cy
l 2 EM29, pin 02 (LGP) and EM13, pin 34 (LGP)
Cy
l 3 EM29, pin 05 (LGW) and EM13, pin 25 (LGW)
Cy
l 4 EM27, pin 03 (LGS) and EM13, pin 33 (LGS)
Cy
l 5 EM29, pin 03 (LGO) and EM13, pin 24 (LGO)
Cy
l 6 EM27, pin 06 (LGR) and EM13, pin 32 (LGR)
Cy
l 7 EM27, pin 05 (LGK) and EM13, pin 23 (LGK)
Cy
l 8 EM29, pin 06 (LGY) and EM13, pin 31 (LGY)
3
Is th
e resistance greater than 5 ohms?
Yes REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the
DTCs. TEST the system for normal operation.
No INSTALL a new ignition module for the affected cy linder(s). CLEAR the DTCs. TEST the system for
normal operation. If the DTC is re peated, contact dealer technical support for advice on possible ECM
failure.
Page 1095 of 2490

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
Page 1096 of 2490

RE
PAIR the circuit between the EGR valve and battery. This circuit includes the EMS relay and the
EMS fuse box. For additional info rmation, refer to the wiring diagrams. CLEAR the DTC. TEST the
system for normal operation.
No GO to A2
.
A2: CHECK THE EGR VALVE COIL WIND
INGS FOR CONTINUITY
Meas
ure t
he resistance between pins 04 and 06 of the EGR valve.
1
Meas
ure t
he resistance between pins 01 and 03 of the EGR valve.
2
Is either resi
stance
greater
than 80 ohms?
Yes INSTALL a new EGR valve.
REFER to Exhaust Gas Recirculation (EGR) Valve
- in thi
s section.
CLEAR the DTC. TEST the syst em for normal operation.
No GO to A3
.
A3: CHECK THE EGR VALVE COIL WINDINGS TO
POWER SUPPLY CIRCUIT FOR CONTINUITY
Meas
ure t
he resistance between pins 02 and 03 of the EGR valve.
1
Meas
ure t
he resistance between pins 05 and 06 of the EGR valve.
2
Is either resi
stance greater
than 80 ohms?
Yes INSTALL a new EGR valve.
REFER to Exhaust Gas Recirculation (EGR) Valve
- in thi
s section.
CLEAR the DTC. TEST the syst em for normal operation.
No GO to A4
.
A4: CHECK THE EGR VALVE T
O ECM
CIRCUITS FOR HIGH RESISTANCE
Disc
onnect the battery negative terminal.
Vehicles with AJ26 engine:
D i
sconnect the ECM electrical connector, EM12
Meas
ure t
he resistance between the following:
PI34, pin
0
4 (YU) and EM12, pin 01 (YU)
PI34,
pi
n 01 (YG) and EM12, pin 02 (YG)
PI34, pin
0
6 (YN) and EM12, pin 03 (YN)
PI34,
pi
n 03 (YR) and EM12, pin 04 (YR)
Vehicles with AJ27 engine:
D i
sconnect the ECM electrical connector, EM85
Meas
ure t
he resistance between the following:
PI34, pin
0
4 (YU) and EM85, pin 03 (YU)
PI34, pi
n 01 (YG) and EM85, pin 04 (YG)
PI34, pi
n 06 (YR) and EM85, pin 09 (YR)
PI34, pi
n 03 (YR) and EM85, pin 10 (YR)
1
Are an
y of the resistances 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 A5
.
A5: CHECK THE EGR VALVE T
O ECM CIRCUITS FOR SHORT TO HIGH VOLTAGE
R
e
connect the battery negative terminal.
1
Meas
ure t
he voltage between the following:
PI34, pin
0
4 (YU) and GROUND
PI34, pin
0
1 (YG) and GROUND
PI34, pin
0
6 (YN) and GROUND
PI34, pin
0
3 (YR) and GROUND
2
Are any of th
e volt
ages 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
Page 1097 of 2490

GO to A6.
A6: CHECK
THE EGR VALVE TO ECM
CIRCUITS FOR SHORT TO GROUND
Meas
ure the resistance between the following:
PI34, pin
04 (YU) and GROUND
PI34, pin
01 (YG) and GROUND
PI34, pin
06 (YN) and GROUND
PI34, pin
03 (YR) and GROUND
1
Are
any of the resistances 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 Contact dealer technical support for advice on possible ECM failure.
Page 1107 of 2490

Intake Air Distribution and Filtering - Intake Air Distribution and Filtering
Description an
d Operation
I
ntake Air Distribution and Filtering - Normally Aspirated Vehicles
Air Intake Asse
mbly
The air cleaner assembly consists of a two piece box containing the air filter, an airflow/temperature unit and the air intake
duct which connects to the top of the throttle assembly. The en gine full load breather feeds into the intake duct from the
bank 1 camshaft cover. A tuned stub on the ai r intake duct reduces the intake noise level.
Mass Air Flow and Temperature Sensors
The intake air is monitored by the Mass Air Flow (MAF) sensor assembly which is fitted at the outlet of the air filter
assembly. Two sensors are incorporated in the MAF sensor assembly, measuring air flow and temperature (temperature
sensor arrowed); both sensors provide anal ogue signal inputs to the engine control module (ECM) and are further described
in Section 303-14.
Page 1109 of 2490

P
arts List
CAUTION: Do not attempt to renew or adjust the throttle cable without consulting the relevant procedure. Two
procedures apply: reconnection of an original cable (19.70.04) or the fitting of a new cable (19.20.06).
The filtered air from the intake duct is drawn downwards through the throttle body to the intake elbow on which the throttle
body is mounted. The airflow through the throttle body is vari ed by the electrically operated throttle valve according to
driver demand and engine mana gement system requirements.
The throttle body assembly has the following features:
Con
vential cable operated input shaft connected to the accelerator pedal.
M
echanical guard to limit throttle angl
e should driver demand exceed ECM co ntrolled parameters and a mechanical
back-up in the event of a throttle motor failure.
Vacuum actuator for operation of the mech anical guard in cru
ise control mode.
Thr
ottle valve (blade) to regula
te air flow into the engine.
Thermostatic air valve to allow and con
t
rol air by-pass around the throttle.
D
C electric motor to operate the thro
ttle in response to ECM control.
Three
sensors (accelerator pedal, mechan
ical guard and the throttle valve) to relay positional information about the
input shaft to the ECM.
R
eturn and control springs fitted to th
e input shaft, mechanical guard, thro ttle valve and dc motor drive gear.
Throttle Cont
rol Modes
There are seven throttle control
modes:
1. 1. Normal
It
em
Par
t Number
De
scription
1—Acce
lerator pedal and mechanic
al guard position sensors
2—Throttl
e (blade)
position sensor
Throttle Body
Page 1110 of 2490

2.2. Cruise
3. 3. Mechanica l
guard
4. 4. Fixed idle
5. 5. Redundancy
6. 6. Full authority
7. 7. Engine shut-down
Normal mode occurs when the EC M uses the mechanical and monitoring arrangem ent of the throttle valve to control throttle
opening. The ECM does not permit driver demand to be exceeded but it can be restricted to allow for such features as
stability / traction control, or engine power limitation.
The ECM determines engine idle speed by controlling the throttle valve motor to vary the blade angle between the non-
adjustable preset limits of the mechanic al guard and the throttle valve motor.
Cruise mode is engaged as a result of the ECM calculating and controlling the required throttle valve opening via the
vacuum system. When the driver releases the throttle pedal, the input shaft disengages from the mechanical guard or the
vacuum actuator pulls the guard away from th e throttle valve. The throttle pedal will feel light should it be pushed again to
accelerate (pressing the pedal further will re-engage the input shaft with the mechanical guard and restore normal feel).
The ECM utilizes sensors to monitor the relative positions of the mechanical guard and throttle valve and adjusts them to
maintain the set cruise speed.
Mechanical guard mode permits full mechanical operation of the throttle if the ECM detects that a problem has been
encountered with the throttle valve position sensor, dc motor, associated harnesses / connecto rs or the ECM.
Fixed idle mode occurs when any two of the three sensors (two input shaft sensors and the mechanical guard sensor) fail.
The ECM will assume values which represent a blade angl e of approximately 2,5° and 1200 rpm (unloaded) maximum
engine speed.
Redundancy mode occurs when any one of the three sensors (two input shaft sensors and the mechanical guard sensor)
fails. The operational pair will be deemed to be safe to co ntinue without intervention, but cruise will be inhibited.
Full authority mode is invoked when a mech anical guard failure occurs which indicates that the guard is stuck fully open.
The red warning lamp will be lit and road speed will be li mited to 120 kph.
Engine shut-down mode will occur followin g multiple failures, such as mechanical guard mode following full authority mode
(or vice versa) or the throttle blade sticks.
Intake Elbow
The intake elbow directs the metered airflow from the electronic throttle to the intake manifold. Stub pipes on both sides of