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Engine Control System (4JH1) 6E-177
DTC P1120 (Symptom Code 1) (Flash Code 21)
Circuit Description
The accelerator pedal position (APP) sensor is mounted
on the intake throttle assembly. The engine control
module (ECM) uses the APP sensors to determine the
amount of acceleration or deceleration desired by the
person driving the vehicle via the fuel injection control.
The APP sensor has the following circuits.
•
5 volts reference circuit
•
Low reference circuit
•
APP sensor signal circuit
The ECM supplies 5 volts to the APP sensor on the 5
volts reference circuit. The ECM also provides a ground
on the low reference circuit. The APP sensor provides a
signal to the ECM on the APP sensor signal circuit,
which is relative to the position changes of the
accelerator pedal angle. The ECM monitors the APP
sensor signal for voltages outside the normal range of
the APP sensor. If the ECM detects an excessively high
APP sensor signal voltage, this DTC will set.
Condition for Running the DTC
•
The ignition switch is ON.
Condition for Setting the DTC
•
The ECM detects that the APP sensor signal
voltage is more than 4.5 volts for 0.5 seconds.
Action Taken When the DTC Sets
•
The ECM illuminates the malfunction indicator
lamp (MIL) when the diagnostic runs and fails.
•
The ECM uses an engine speed substitution of
1400 RPM.
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
•
If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
DTC P1120 (Symptom Code 1) (Flash Code 21)
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.
4. Monitor the Diagnostic Trouble Code (DTC)
Information with the scan tool.
Does the DTC fail this ignition?
Go to Step 3
Go to Diagnostic
Aids
3
1. Turn OFF the ignition.
2. Disconnect the accelerator pedal position (APP)
sensor harness connector.
3. Turn ON the ignition, with the engine OFF.
4. Observe the Accelerator Pedal Position (APP)
parameter with the scan tool.
Does the APP parameter less than the specified
value?
1%
Go to Step 4
Go to Step 5
4
1. Turn OFF the ignition.
2. Connect a test lamp between the low reference
circuit of the APP sensor harness (pin 1 of E-22
connector) and battery voltage.
3. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?
Go to Step 11
Go to Step 8
5
1. Turn OFF the ignition.
2. Connect a DMM between the 5 volts reference
circuit of the APP sensor harness (pin 3 of E-22
connector) and a known good ground.
3. Turn ON the ignition, with the engine OFF.
Is the DMM voltage more than the specified value?
4.5 volts
Go to Step 6
Go to Step 9
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...