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6E-112 Engine Control System (4JH1)
DTC P0251 (Symptom Code 7) (Flash Code 53)
Circuit Description
The engine control module (ECM) calculates the
desired fuel injection quantity and timing using data sent
from various sensors. These desired data are sent to
the fuel injection pump control unit (PCU) via a
controller area network (CAN) communication bus. The
PCU also receives signals from the internal inputs:
pump camshaft position (CMP) sensor that is located
inside the fuel injection pump to determine the cam ring
rotation angle and the fuel injection pump speed. The
fuel temperature (FT) sensor is internal the PCU. These
values are used to compare the desired values sent
from the ECM then PCU determines the injection timer
piston position and fuel injection quantity, and actuates
timing control valve (TCV) & fuel injection solenoid
valve based on control maps in the PCU. The PCU also
compares the engine speed signal sent from the ECM
and the fuel injection pump speed. If the PCU detects
that the doubled fuel injection pump speed is
excessively lower than engine speed, this DTC will set.
Condition for Running the DTC
•
The fuel injection pump CMP sensor signal is
generated.
•
The crankshaft position (CKP) sensor signal is
generated.
•
The engine speed is higher than 500 RPM.
Condition for Setting the DTC
•
The PCU detects that the doubled fuel injection
pump speed is lower than engine speed by 690
RPM for longer than 0.2 seconds.
Action Taken When the DTC Sets
•
The ECM illuminates the malfunction indicator
lamp (MIL) when the diagnostic runs and fails.
•
The ECM cuts fuel injection.
Condition for Clearing the MIL/DTC
•
The ECM turns OFF the MIL when the diagnostic
runs and does not fail.
•
A history DTC clears after 40 consecutive driving
cycles without a fault. Or clear with the scan tool.
Diagnostic Aids
•
Electrical or magnetic interference may affect
intermittent condition.
•
If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
Notice:
•
Fuel injection pump CMP sensor is internal to the
fuel injection pump assembly.
•
PCU is part of the fuel injection pump assembly.
DTC P0251 (Symptom Code 7) (Flash Code 53)
Schematic Reference:
Engine Controls Schematics
Connector End View Reference:
Engine Controls
Connector End Views or Engine Control Module (ECM)
Connector End Views
Step Action
Value(s)
Yes
No
1
Did you perform the Diagnostic System Check-
Engine Controls?
Go to Step 2
Go to Diagnostic
System Check-
Engine Controls
2
1. Install the scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine. If the engine does not start,
crank over the engine.
4. Monitor the Diagnostic Trouble Code (DTC)
Information with the scan tool.
Is DTC P0335 (Symptom Code B, D or E), P1335
(Symptom Code A) or P1345 (Symptom Code A)
set?
Go to Applicable
DTC
Go to Step 3
3
1. Start the engine.
2. Monitor the DTC Information with the scan tool.
3. Accelerate the engine between idle and W.O.T.
(accelerator pedal full travel) many times.
Does the DTC fail this ignition?
Go to Step 4
Go to Diagnostic
Aids
Summary of Contents for 4ja1
Page 2: ......
Page 34: ...6A 12 ENGINE MECHANICAL Cooling and Lubricating System N m kg m lb ft RTW46AXF000701...
Page 35: ...ENGINE MECHANICAL 6A 13 Intake Manifold 4JA1TC 4JH1TC N m kg m lb ft RTW36AXF000201...
Page 36: ...6A 14 ENGINE MECHANICAL EGR Valve EGR Pipe EGR Cooler RTW46AXF000801...
Page 37: ...ENGINE MECHANICAL 6A 15 Exhaust Manifold and Turbocharger 4JA1L RTW46AXF000901...
Page 39: ...ENGINE MECHANICAL 6A 17 Engine Electricals N m kg m lb ft RTW36AXF000501...
Page 40: ...6A 18 ENGINE MECHANICAL Fuel Injection System 4JA1L N m kg m lb ft RTW86AXF000201...
Page 41: ...ENGINE MECHANICAL 6A 19 Fuel Injection System 4JA1TC N m kg m lb ft RTW46AXF001201...
Page 42: ...6A 20 ENGINE MECHANICAL Fuel Injection System 4JH1TC N m kg m lb ft RTW46AXF001301...
Page 43: ...ENGINE MECHANICAL 6A 21 Engine Mounting Bracket N m kg m lb ft 022R300001...
Page 162: ...MEMO...
Page 187: ...FUEL SYSTEM 6C 5 For EURO III model RTW46AMF000201...
Page 220: ...MEMO...
Page 225: ...ENGINE ELECTRICAL 6D 5 TORQUE SPECIFICATIONS GENERATOR N m kg m Ib ft RTW86DLF000101...
Page 226: ...6D 6 ENGINE ELECTRICAL STARTER MOTOR N m kg m Ib ft RTW86DLF000201...
Page 254: ...MEMO...
Page 261: ...Engine Control System 4JH1 6E 7 Engine Controls Schematics Power Distribution 1 RTW86EXF004801...
Page 262: ...6E 8 Engine Control System 4JH1 Power Distribution 2 RTW86EXF004901...
Page 263: ...Engine Control System 4JH1 6E 9 Starting System RTW86EXF005001...
Page 264: ...6E 10 Engine Control System 4JH1 Charging System RTW86EXF005101...
Page 265: ...Engine Control System 4JH1 6E 11 ECM Power and PCU RTW86EXF003001...
Page 266: ...6E 12 Engine Control System 4JH1 ECM Ground and DLC RTW86EXF005201...
Page 267: ...Engine Control System 4JH1 6E 13 Gauges and Warning Lamps RTW86EXF003201...
Page 269: ...Engine Control System 4JH1 6E 15 MAF IAT Vacuum Pressure and ECT Sensors RTW86EXF003401...
Page 275: ...Engine Control System 4JH1 6E 21 1 Legend 1 Vehicle Speed Sensor VSS...
Page 536: ...MEMO...
Page 558: ...6H 2 ACCELERATOR CONTROL REMOVAL AND INSTALLATION 4JA1T L RHD RTW46HLF000301...
Page 559: ...ACCELERATOR CONTROL 6H 3 4JA1T L LHD RTW46HLF000601...
Page 560: ...6H 4 ACCELERATOR CONTROL 4JA1TC 4JH1TC RHD RTW46HLF000201...
Page 561: ...ACCELERATOR CONTROL 6H 5 4JA1TC 4JH1TC LHD PTW46BMF000101...
Page 564: ...No TF4JE WE 1101...