fuel pressure ISUZU TF SERIES 2004 Service Manual

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–75
When control current flows to the timing control valve
(TCV) coil, the valve needle opens and the fuel annular
chamber flows through the orifice to the feed pump inlet.
Consequently, the pressure of the annular chamber
decreases and the hydraulic stopper is moved to the
retard side.
The timing control valve (TCV) acts as a variable
throttle, using the rapid opening and closing (cycling) of
the valve needle in the timing control valve (TCV).
At normal operation, the TCV controls the pressure
acting on the annular chamber so that the hydraulic
stopper cam move to any position, from the retard
position to the advance position. At this time, the duty
ratio is set by the pump control unit (PSG).
Duty ratio is the ratio of the time that the timing control
valve (TCV) is opened to one complete timing control
valve (TCV) operating cycle. A duty ratio change of
100% to 0% is an advance in injection timing. (The
VP44 displays an ON duty ratio.)The engine control module (ECM) contains
characteristic maps of the start of injection,
corresponding to engine operating conditions (engine
load, engine speed and engine coolant temperature).
The pump control unit (PSG) is constantly comparing
the set start of injection timing and the actual start of
injection timing. If there is a difference, the timing
control valve (TCV) is controlled by the duty ratio. (The
actual start of injection timing is determined from the
pump camshaft speed sensor.) (1) Coil
(2) From Annular Chamber
(3) To Feed Pump
(4) Orifice
(5) Valve Needle
Engine Load
Engine Speed
Engine Coolant
TemperatureEngine
Control
Module
(ECM)Pump
Control
Unit
(PSG)
Pump Camshaft
Speed Sensor
Timing
Control
Valve
(TCV)

6E–114 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONSECM Diagnostic Trouble CodesFlash
CodeCodeSymptom
CodeMILDTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure PartsRelated
ECM Pin
No.Related
Multiple
DTC4JA1-TC
(MT)4JH1-TC
(MT)4JH1-TC
(AT)
65 P0100 7 ON Mass Air Flow (MAF) Sensor
Voltage Supply Circuit High
InputMAF sensor power supply
voltage is more than 5.2V.ECM uses mass air flow
1600mg/strk & EGR 10%
conditions as substitute.MAF sensor power supply
voltage is below 5.2V.1. Sensor power supply
circuit short to battery
voltage circuit.
2. MAF sensor malfunction.
3. ECM malfunction.83 —
9 ON Mass Air Flow (MAF) Sensor
Voltage Supply Circuit Low
InputMAF sensor power supply
voltage is below 4.6V.MAF sensor power supply
voltage is more than 4.6V.1. Sensor power supply
circuit short to ground
c i r c u i t .
2. MAF sensor malfunction.
3. ECM malfunction.83 —
B ON Mass Air Flow (MAF) Sensor
Output Circuit Low Input1. Engine speed is between
600rpm and 5000rpm.
2. MAF sensor output is
below -33.7mg/strk.MAF sensor output is more
than -27.4mg/strk.1. Sensor power supply
circuit open circuit.
2. Sensor signal circuit
open or short to ground
c i r c u i t .
3. Sensor heater harness
o p e n c i r c u i t .
4. Poor connector
c o n n e c t i o n .
5. MAF sensor malfunction.
6. ECM malfunction.8 3 /
88P0110(1)
C ON Mass Air Flow (MAF) Sensor
Output Circuit High Input1. Engine speed is between
600rpm and 5000rpm.
2. MAF sensor output is
more than 1378mg/strk
(4JA1-TC) or 1784mg/
strk (4JH1-TC).MAF sensor output is below
1378mg/strk (4JA1-TC) or
1784mg/strk (4JH1-TC).1. Sensor signal circuit
short to voltage circuit.
2. Sensor ground circuit
open or short to voltage
c i r c u i t .
3. MAF sensor malfunction.
4. ECM malfunction.8 8 /
92P0110(1)
34 P0105 1 ON Vacuum Pressure Sensor
Circuit High InputVacuum sensor output
voltage is more than 4.4V.1. Fuel injection quantity is
r e d u c e d .
2. ECM use 615hpa
conditions for
turbocharger waste gate
control.Vacuum sensor output
voltage is below 4.4V.1. Sensor signal circuit
short to voltage circuit.
2. Sensor ground circuit
open or short to voltage
c i r c u i t .
3. Vacuum sensor
m a l f u n c t i o n .
4. ECM malfunction.8 5 /
93P0115(1) —
2 ON Vacuum Pressure Sensor
Circuit Low InputVacuum sensor output
voltage is below 0.5V.Vacuum sensor output
voltage is more than 0.5V.1. Sensor power supply
circuit open circuit.
2. Sensor signal circuit
open or short to ground
c i r c u i t .
3. Poor connector
c o n n e c t i o n .
4. Vacuum sensor
m a l f u n c t i o n .
5. ECM malfunction.8 2 /
85——

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–115
34 P0105 7 ON Vacuum Pressure Sensor
Voltage Supply Circuit High
InputVacuum sensor power
supply voltage is more than
5.2V.1. Fuel injection quantity is
r e d u c e d .
2. ECM use vacuum sensor
output voltage 5.0V
condition as substitute.Vacuum sensor power
supply voltage is below 5.2V.1. Sensor power supply
circuit short to battery
voltage circuit.
2. Vacuum sensor
m a l f u n c t i o n .
3. ECM malfunction.82 — —
9 ON Vacuum Pressure Sensor
Voltage Supply Circuit Low
InputVacuum sensor power
supply voltage is below 4.5V.Vacuum sensor power
supply voltage is more than
4.5V.1. Sensor power supply
circuit short to ground
c i r c u i t .
2. Vacuum sensor
m a l f u n c t i o n .
3. ECM malfunction.82 — —
23 P0110 1 ON Intake Air Temperature (IAT)
Sensor Circuit High InputIAT sensor output voltage is
more than 4.7V.ECM use 0 deg. C conditions
as substitute.IAT sensor output voltage is
below 4.7V.1. Sensor signal circuit
open or short to voltage
c i r c u i t .
2. Sensor ground circuit
open or short to voltage
c i r c u i t .
3. Poor connector
c o n n e c t i o n
4. IAT sensor malfunction.
5. ECM malfunction.8 4 /
92P0100(B)/







P0100(C)
2 ON Intake Air Temperature (IAT)
Sensor Circuit Low InputIAT sensor output voltage is
below 0.3V.IAT sensor output voltage is
more than 0.3V.1. Sensor signal circuit
short to ground circuit.
2. IAT sensor malfunction.
3. ECM malfunction.84 —
14 P0115 1 ON Engine Coolant Temperature
(ECT) Sensor Circuit High
InputECT sensor output voltage is
more than 4.7V.1. ECM uses fuel
temperature as
s u b s t i t u t e .
2. ECM uses 60 deg. C
condition for injection
t i m i n g c o n t r o l .
3. ECM uses -25 deg. C
condition (4JA1-TC) or -
15 deg. C condition
(4JH1-TC) for glow time
control.ECT sensor output voltage is
below 4.7V.1. Sensor signal circuit
open or short to voltage
c i r c u i t .
2. Sensor ground circuit
open or short to voltage
c i r c u i t .
3. Poor connector
c o n n e c t i o n
4. ECT sensor malfunction.
5. ECM malfunction.8 9 /
93P0105(1)
2 ON Engine Coolant Temperature
(ECT) Sensor Circuit Low
InputECT sensor output voltage is
below 0.3V.ECT sensor output voltage is
more than 0.3V.1. Sensor signal circuit
short to ground circuit.
2. ECT sensor malfunction.
3. ECM malfunction.89 —
15 P0180 B ON Fuel Temperature Sensor
Circuit Range/PerformanceFT sensor output is high
temperature (more than 150
deg. C) or low temperature
(below -40 deg. C).The ECM use 75 deg. C
conditions as substitute.FT sensor output is correct
temperature range between
150 deg. C and -40 deg. C.1 . E C M m a l f u n c t i o n .
2. PSG (pump control unit)
malfunction.—— Flash
CodeCodeSymptom
CodeMILDTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure PartsRelated
ECM Pin
No.Related
Multiple
DTC4JA1-TC
(MT)4JH1-TC
(MT)4JH1-TC
(AT)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–117
64 P0243 3 ON Turbocharger Wastegate
Solenoid "A" Range/
Performance1. Intake air temperature is
between -50 deg. C and
2 0 0 d e g . C .
2. Engine coolant
temperature is between -
50 deg. C and 150 deg.
C .
3. Barometric pressure is
between 0hpa and
3 5 0 0 h p a .
4. Low vacuum pressure
condition. (Desired
vacuum pressure - actual
vacuum pressure is more
than 50hpa.)1. Fuel injection quantity is
r e d u c e d .
2. EGR EVRV becomes
1 0 % c o n d i t i o n . 1. Engine speed is between
500rpm and 6000rpm.
2. Correct vacuum pressure
condition. (Desired
vacuum pressure - actual
vacuum pressure is less
than 50hpa.)1. Turbocharger wastegate
control EVRV
m a l f u n c t i o n .
2. Vacuum line is
o b s t r u c t e d .
3. Vacuum is leaking.
4. Vacuum pump
m a l f u n c t i o n .
5. Vacuum sensor
m a l f u n c t i o n .
6. Turbocahrger wastegate
v a l v e m a l f u n c t i o n .
7. ECM malfunction.8 5 /
96——
4 ON Turbocharger Wastegate
Solenoid "A" Low Wastegate control EVRV
circuit open or short to
ground circuit.1. Fuel injection quantity is
r e d u c e d .
2. EGR EVRV becomes
1 0 % c o n d i t i o n .
3. Wastegate control EVRV
becomes 32% condition.Wastegate control EVRV
circuit is correct condition.1. Wastegate control EVRV
circuit open or short to
g r o u n d c i r c u i t .
2. Wastegate control EVRV
m a l f u n c t i o n .
3. ECM malfunction.96 — —
5 ON Turbocharger Wastegate
Solenoid "A" Range/
Performance1. Intake air temperature is
between -50 deg. C and
2 0 0 d e g . C .
2. Engine coolant
temperature is between -
50 deg. C and 150 deg.
C .
3. Barometric pressure is
between 0hpa and
3 5 0 0 h p a .
4. High vacuum pressure
condition. (Desired
vacuum pressure - actual
vacuum pressure is less
than -50hpa.)1. Fuel injection quantity is
r e d u c e d .
2. EGR EVRV becomes
1 0 % c o n d i t i o n . 1. Engine speed is between
500rpm and 6000rpm.
2. Correct vacuum pressure
condition. (Desired
vacuum pressure - actual
vacuum pressure is more
than -50hpa.)1. Turbocharger wastegate
control EVRV
m a l f u n c t i o n .
2. Vacuum regulating valve
m a l f u n c t i o n .
3. Vacuum pump
m a l f u n c t i o n .
4. Vacuum sensor
m a l f u n c t i o n .
5. ECM malfunction.8 5 /
96——
6 ON Turbocharger Wastegate
Solenoid "A" Malfunction1. Engine coolant
temperature is between -
50 deg. C and 150 deg.
C .
2. EGR control EVRV 0%
c o n d i t i o n .
3. No DTC relating to MAF
sensor, vacuum sensor &
I A T s e n s o r .
4. Large amount of mass air
flow. (= Incorrect boost
pressure condition)
(Desired mass air flow -
actual mass air flow is
less than -56mg/strk.)1. Correct amount of mass
air flow. (= Correct boost
pressure condition)
(Desired mass air flow -
actual mass air flow is
more than -56mg/strk.)1. Turbocharger wastegate
a c t u a t o r m a l f u n c t i o n .
2. Vacuum line malfunction.

































3. ECM malfunction.
——— Flash
CodeCodeSymptom
CodeMILDTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure PartsRelated
ECM Pin
No.Related
Multiple
DTC4JA1-TC
(MT)4JH1-TC
(MT)4JH1-TC
(AT)

6E–118 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
64 P0243 8 ON Turbocharger Wastegate
Solenoid "A" HighWastegate control EVRV
circuit short to voltage circuit.1. Fuel injection quantity is
r e d u c e d .
2. EGR EVRV becomes
1 0 % c o n d i t i o n .
3. Wastegate control EVRV
becomes 32% condition.Wastegate control EVRV
circuit is correct condition.1. Wastegate control EVRV
circuit short to voltage
c i r c u i t .
2. Wastegate control EVRV
m a l f u n c t i o n .
3. ECM malfunction.96 — —
53 P0251 6 ON Injection Pump Malfunction 1. No pump camshaft
s p e e d s e n s o r e r r o r .
2. High pressure solenoid
valve control pulse width
does not match with
desired fuel injection
quantity. 1. MAB (fuel cutoff solenoid
v a l v e ) i s o p e r a t e d .
2. Desired injection quantity
becomes 0mg/strk.No recovery until condition
match in the next ignition key
cycle.1. PSG (pump control unit)
m a l f u n c t i o n .
2. Pump camshaft speed
sensor malfunction.——
7 ON Injection Pump Malfunction 1. No pump camshaft
s p e e d s e n s o r e r r o r .
2 . N o C K P s e n s o r e r r o r .
3. Difference of engine
speed and doubled pump
camshaft speed is more
than 720rpm (4JA1-TC)
or 690rpm (4JH1-TC). 1. No pump camshaft
s p e e d s e n s o r e r r o r .
2 . N o C K P s e n s o r e r r o r .
3. Difference of engine
speed and doubled pump
camshaft speed is below
800rpm (4JA1-TC) or
6 9 0 r p m ( 4 J H 1 - T C ) .
No recovery until in the
next ignition key cycle. 1. Missing CKP sensor
p u l s e s .
2. Electrical interference.
3. Magnetic interference.
4. PSG (pump control unit)
malfunction.91 —
9 ON Injection Pump Malfunction No pump map programmed
in the PSG (pump control
unit) or PSG malfunction.No recovery until condition
match in the next ignition key
cycle.PSG (pump control unit)
malfunction. — —
A ON Injection Pump Malfunction EEPROM or A/D converter
malfunction in the PSG
(pump control unit).Fuel injection quantity is
reduced.EEPROM or A/D converter
no malfunction in the PSG
( p u m p c o n t r o l u n i t ) .
No recovery until in the next
ignition key cycle.PSG (pump control unit)
malfunction.
——
B ON Injection Pump Malfunction PSG (pump control unit)
recognized high pressure
solenoid valve drive circuit
error.No fail-safe function. No recovery until condition
match in the next ignition key
cycle.PSG (pump control unit)
malfunction.
——
D ON Injection Pump Malfunction PSG (pump control unit)
could not measure the high
pressure solenoid valve drive
voltage.PSG (pump control unit)
malfunction.
——
E ON Injection Pump Malfunction ECM could not accept PSG
(pump control unit) message.1. MAB (fuel cutoff solenoid
v a l v e ) i s o p e r a t e d .
2. Desired injection quantity
becomes 0mg/strk.ECM accepts PSG (pump
control unit) message.1. CAN high circuit open,
short to ground or short
t o v o l t a g e c i r c u i t .
2. CAN low circuit open,
short to ground or short
t o v o l t a g e c i r c u i t .
3 . E C M m a l f u n c t i o n .
4. PSG (pump control unit)
malfunction.9 9 /
100P1650(A)/











P1651(B) Flash
CodeCodeSymptom
CodeMILDTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure PartsRelated
ECM Pin
No.Related
Multiple
DTC4JA1-TC
(MT)4JH1-TC
(MT)4JH1-TC
(AT)

6E–120 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
67 P0381 4 ON Glow Plug Indicator Circuit
Voltage LowGlow plug indicator circuit
open or short to ground
circuit.No fail-safe function. Glow plug indicator circuit is
correct condition.1. Glow plug indicator
circuit open or short to
g r o u n d c i r c u i t .
2. Glow plug indicator lamp
m a l f u n c t i o n .
3. ECM malfunction.43 —
8 ON Glow Plug Indicator Circuit
Voltage HighGlow plug indicator circuit
short to voltage circuit.ECM malfunction.
——
32 P0400 3 ON Exhaust Gas Recirculation
Flow Excessive Detected1. Intake air temperature is
between 15 deg. C and
1 0 0 d e g . C .
2. Engine coolant
temperature is between
55 deg. C and 100 deg.
C (4JA1-TC) or 35 deg. C
and 100 deg. C (4JH1-
T C ) .
3. Barometric pressure is
between 850hpa and
1 1 0 0 h p a .
4. Small amount of mass air
flow. (Desired mass air
flow - mass air flow is
more than 150mg/strk)Fuel injection quantity is
reduced. 1. Engine speed is between
1500rpm and 3100rpm
(4JA1-TC) or 1500rpm
and 3200rpm (4JH1-TC).



















2. Injection quantity is
below 32mg/strk (4JA1-
TC) or 40mg/stk (4JH1-
T C ) .
3. Correct amount of mass
air flow.1. EGR valve is stuck at
o p e n p o s i t i o n .
2. EGR EVRV malfunction.
3 . A i r i n t a k e i s o b s t r u c t e d .
4. Air intake is leaking.
5. MAF sensor malfunction.
6. ECM malfunction.
8 8 /
97—
4 ON Exhaust Gas Recirculation
Circuit Short to Ground or
Open CircuitEGR EVRV circuit open or
short to ground circuit.Fuel injection quantity is
reduced and EGR EVRV
10% conditions as substitute.EGR EVRV circuit is correct
condition.1. EGR EVRV circuit open
or short to ground circuit.
2. EGR EVRV malfunction.
3. ECM malfunction.97 —
5 ON Exhaust Gas Recirculation
Flow Insufficient Detected1. Intake air temperature is
between 15 deg. C and
100 deg. C.
2. Engine coolant
temperature is between
55 deg. C and 100 deg.
C (4JA1-TC) or 35 deg. C
and 100 deg. C (4JH1-
T C ) .
3. Barometric pressure is
between 850hpa and
1 1 0 0 h p a .
4. Large mount of mass air
flow. (Desired mass air
flow - mass air flow is
below -150 mg/strk)Fuel injection quantity is
reduced. 1. Engine speed is between
1500rpm and 3100rpm
(4JA1-TC) or 1500rpm
and 3200rpm (4JH1-TC).



















2. Injection quantity is
below 32mg/strk (4JA1-
TC) or 40mg/stk (4JH1-
T C ) .
3. Correct amount of mass
air flow.1. EGR valve is stuck at
c l o s e p o s i t i o n .
2. EGR valve operating
vacuum hose is clogged
or disconnected.
3. EGR EVRV malfunction.


4. MAF sensor signal circuit
short to voltage circuit.
5. MAF sensor malfunction.
6. ECM malfunction.8 8 /
97—
8 ON Exhaust Gas Recirculation
Circuit Short to BatteryEGR EVRV circuit short to
voltage circuit.Fuel injection quantity is
reduced & EGR EVRV 10%
conditions as substitute.EGR EVRV circuit is correct
condition.1. EGR EVRV circuit short
t o v o l t a g e c i r c u i t .
2. EGR EVRV malfunction.
3. ECM malfunction.97 — Flash
CodeCodeSymptom
CodeMILDTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure PartsRelated
ECM Pin
No.Related
Multiple
DTC4JA1-TC
(MT)4JH1-TC
(MT)4JH1-TC
(AT)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–127
51 P1630 A ON Fuel Injection Quantity
Circuit MalfunctionThe PSG (pump control unit)
detects high pressure
solenoid valve control circuit
malfunction due to high
current.Fuel injection quantity is
reduced.The PSG (pump control unit)
detects correct high pressure
solenoid valve control circuit.PSG (pump control unit)
malfunction.
——
B ON Fuel Injection Quantity
Circuit MalfunctionThe PSG (pump control unit)
detects high pressure
solenoid valve control circuit
malfunction due to
continuous current.1. MAB (fuel cutoff solenoid
v a l v e ) i s o p e r a t e d .
2. Desired injection quantity
becomes 0mg/strk.No recovery. PSG (pump control unit)
malfunction.
——
44 P1650 A ON CAN Device Offline CAN controller detects Bus-
off or canceling.MAB (fuel cutoff solenoid
v a l v e ) i s o p e r a t e d . CAN controller detects
correct Bus signal.1. CAN high circuit open,
short to ground or short
t o v o l t a g e c i r c u i t .
2. CAN low circuit open,
short to ground or short
t o v o l t a g e c i r c u i t .
3. Poor connector
c o n n e c t i o n .
4. Electrical interference.
5. ECM malfunction.
6. PSG (pump control unit)
malfunction.9 9 /
100P1651(B)
B ON CAN Device Hang-up CAN controller does not
react under engine running.CAN controller reacts
correctly under engine
running.1 . E C M m a l f u n c t i o n .
2. PSG (pump control unit)
malfunction.——
45 P1651 A ON CAN Malfunction The PSG (pump control unit)
does not recognize CAN
signal from the CAN
controller.1. MAB (fuel cutoff solenoid
v a l v e ) i s o p e r a t e d .
2. Desired injection quantity
becomes 0mg/strk.The PSG (pump control unit)
recognizes CAN signal from
the CAN controller.1 . E C M m a l f u n c t i o n .
2. PSG (pump control unit)
malfunction.——
B ON CAN Malfunction The ECM does not read CAN
signal from the PSG (pump
control unit).The ECM reads CAN signal
from the PSG (pump control
unit).1. CAN high circuit open,
short to ground or short
to voltage circuit.
2. CAN low circuit open,
short to ground or short
to voltage circuit.
3. Poor connector
connection.
4. Electrical interference.
5. ECM malfunction.
6. PSG (pump control unit)
malfunction.9 9 /
100P1650(A)
77 P1690 4 OFF Check Engine Lamp (MIL)
Circuit Voltage LowCheck engine lamp circuit
open or short to ground
circuit.No fail-safe function. Check engine lamp circuit is
correct condition.1. Check engine lamp
circuit open or short to
g r o u n d c i r c u i t .
2. Check engine lamp
malfunction
3. ECM malfunction.42 B****
8 OFF Check Engine Lamp (MIL)
Circuit Voltage HighCheck engine lamp circuit
short to voltage circuit.ECM malfunction.
—— Flash
CodeCodeSymptom
CodeMILDTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure PartsRelated
ECM Pin
No.Related
Multiple
DTC4JA1-TC
(MT)4JH1-TC
(MT)4JH1-TC
(AT)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–141
Condition for setting the DTC and action taken when the DTC sets
Circuit description
The ECM monitors altitude from the barometric
pressure sensor. To apply specified vacuum pressure to
the turbocharger wastegate valve, ECM sends control
signal to the wastegate control solenoid depending on
altitude.
Then, apply vacuum pressure to the turbocharger
wastegate valve is monitored by the ECM form the
vacuum pressure sensor output signal. The ECM
controls wastegate control solenoid based on signal
from vacuum pressure sensor output.
The output voltage ex cessively high or low, DTC P0105
(Symptom Code 1) or P0105 (Symptom Code 2) will be
stored.
The supply voltage is out of range, DTC P0105
(Symptom Code 7) or P0105 (Symptom Code 9) will be
stored.
Diagnostic Aids
An intermittent may be caused by the following:
Poor connections.
Misrouted harness.
Rubbed through wire insulation.
Broken wire inside insulation.
Check for the following conditions:
Poor connection at ECM-Inspect harness connectors
for backed out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal to wire connection.
Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the DTC P0105 display on the Tech 2 while moving
connectors and wiring harnesses. A change in the
display will indicate the location of the fault.
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
34 P0105 1 ON Vacuum Pressure Sensor
Circuit High InputVacuum sensor output
voltage is more than 4.4V.1. Fuel injection quantity is
r e d u c e d .
2. ECM use 615hpa
conditio ns for
turbo cha rge r wa ste gate
contro l. 2 ON Vacuum Pressure Sensor
Circuit Low InputVacuum sensor output
voltage is below 0.5V.
7 ON Vacuum Pressure Sensor
Volta ge Supply Circuit High
InputVacuum senso r po wer supply
voltage is more than 5.2V.1. Fuel injection quantity is
r e d u c e d .
2. ECM use vacuum sensor
output voltage 5.0V
condition as substitute. 9 ON Vacuum Pressure Sensor
Volta ge Supply Circuit Lo w
InputVacuum senso r po wer supply
voltage is below 4.5V.

6E–184 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Condition for setting the DTC and action taken when the DTC sets
Circuit description
The ECM monitors altitude from the barometric
pressure sensor. To apply specified vacuum pressure to
the turbocharger wastegate valve, ECM sends control
signal to the wastegate control solenoid depending on
altitude.
Then, apply vacuum pressure to the turbocharger
wastegate valve is monitored by the ECM form the
vacuum pressure sensor output signal. The ECM
controls wastegate control solenoid based on signal
from vacuum pressure sensor output.
If the vacuum pressure sensor detected vacuum
pressure is excessively low or high due to faulty vacuum
line, vacuum pump or turbocharger wastegate valve,
DTC P0243 (Symptom Code 3), P0243 (Symptom Code
5) or P0243 (Symptom Code 6) will be stored.
If the wastegate control solenoid circuit is open or short
to ground circuit, DTC P0243 (Symptom Code 4) will be
stored.
If the wastegate control solenoid circuit is short to
voltage circuit, DTC P0243 (Symptom Code 8) will be
stored.
Diagnostic Aids
An intermittent may be caused by the following:
Poor connections.
Misrouted harness.
Rubbed through wire insulation.
Broken wire inside insulation.
Turbocharger wastegate valve sticking or broken.
Misrouted vacuum hose.
Faulty vacuum pump or regulating valve.
Check for the following conditions:
Poor connection at ECM-Inspect harness connectors
for backed out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal to wire connection.
Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the DTC P0243 display on the Tech 2 while moving
connectors and wiring harnesses. A change in the
display will indicate the location of the fault.
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
64 P0243 3 ON Turbocharger Wastegate
So le no id "A" Ra nge/
Pe rfo rma nce1. Intake air temperature is
between -50 deg. C and
2 0 0 d e g . C .
2. Engine coolant
temperature is between -
50 deg. C and 150 deg.
C. 1. Fuel injection quantity is
r e d u c e d .
2. EGR EVRV becomes 10%
co nditio n.
4 ON Turbocharger Wastegate
So le no id "A" Lo w Wastegate control EVRV
circuit open or short to ground
circuit.1. Fuel injection quantity is
r e d u c e d .
2. EGR EVRV becomes 10%
c o n d i t i o n .
3. Wastegate control EVRV
be co mes 32% conditio n.
5 ON Turbocharger Wastegate
So le no id "A" Ra nge/
Pe rfo rma nce1. Intake air temperature is
between -50 deg. C and
2 0 0 d e g . C .
2. Engine coolant
temperature is between -
50 deg. C and 150 deg.
C. 1. Fuel injection quantity is
r e d u c e d .
2. EGR EVRV becomes 10%
co nditio n.
6 ON Turbocharger Wastegate
So le no id "A" Malfunctio n1. Engine coolant
temperature is between -
50 deg. C and 150 deg.
C .
2. EGR contro l EVRV 0%
co nditio n.
8 ON Turbocharger Wastegate
So le no id "A" HighWastegate control EVRV
circuit short to voltage circuit.1. Fuel injection quantity is
r e d u c e d .
2. EGR EVRV becomes 10%
c o n d i t i o n .
3. Wastegate control EVRV
be co mes 32% conditio n.

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–197
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM is calculates an injection quantity and an
injection timing using the various sensors. And the PSG
controls the high pressure solenoid valve depending on
programmed pump map data.
The signal of desired injection quantity and actual injec-
tion quantify are ex changed via the CAN-bus between
the PSG and ECM.
If the relation of engine speed signal and doubled pump
camshaft speed signal ex cessively large, DTC P0251
(Symptom Code 7) will be stored.
If the CAN high or low circuit is defected, DTC P0251
(Symptom Code E) will be stored.
Diagnostic Aids
An intermittent may be caused by the following:
Poor connections.
Misrouted harness.
Rubbed through wire insulation.
Broken wire inside the insulation.
Check for the following conditions:
Poor connection at ECM and PSG-Inspect harness
connectors for backed out terminals, improper
mating, broken locks, improperly formed or damaged
terminals, and poor terminal to wire connection.
Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the “Injection Quantity” display on the Tech2 while
moving connectors and wiring harness related to the
sensor.
Diagnostic Trouble Code (DTC) P0251 (Symptom Code 6) (Flash Code 53)
Injection Pump Malfunction
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
53 P0251 6 ON Injection Pump Malfunction 1. No pump camshaft speed
se nsor erro r.
2. High pressure solenoid
v a lv e co ntro l pulse w idth
doe s no t ma tch with
desired fuel injection quan-
tity. 1. MAB (fuel cutoff solenoid
valve) is operated.
2. Desired injection quantity
becomes 0mg/strk.
7 ON Injection Pump Malfunction 1. No pump camshaft speed
se nsor erro r.
2. No CKP senso r e rror.
3. Difference of engine speed
and doubled pump cam-
shaft speed is more than
720rpm (4JA1-TC) or 690
rpm (4JH1-TC).
9 ON Injection Pump Malfunction No pump map programmed in
the PSG (pump co ntrol unit)
or PSG malfunction.
A ON Injection Pump Malfunction EEPROM or A/D converter
malfunctio n in the PSG (pump
control unit).Fuel inje ctio n qua ntity is
reduced.
B ON Injection Pump Malfunction PSG (pump control unit) rec-
ognized high pressure sole -
noid valve drive circuit error.No fa il-sa fe fun ctio n.
D ON Injection Pump Malfunction PSG (pump control unit) could
no t me asure the high pres-
sure solenoid valve drive volt-
age.
E ON Injection Pump Malfunction ECM could not accept PSG
(pump co ntrol unit) messa ge.1. MAB (fuel cutoff solenoid
valve) is operated.
2. Desired injection quantity
becomes 0mg/strk.
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2Go to On Board
Diagnostic
(OBD) System
Check