Perkins NJ Series Troubleshooting Manual page 145

SENR9982-01
Expected Result:
The duty cycle is between approximately 10 and 22
percent with the throttle pedal assembly in the low
idle position, and the duty cycle is between 75 and
90 percent with the throttle pedal assembly in the
high idle position.
Results:
•
OK – A good signal from the digital throttle position
sensor is reaching the ECM. Verify that the ECM
is receiving the correct battery voltage. If the ECM
is receiving the correct battery voltage, temporarily
connect a test ECM and verify that the fault is
resolved. If the fault is rectified with the test ECM,
reconnect the suspect ECM. If the fault returns with
the suspect ECM, replace the ECM. STOP.
• Not OK – There is a fault with signal wire in the
harness. Proceed to Test Step 11.
Test Step 10. Remove the Digital Throttle
Position Sensor from the Throttle Pedal
Assembly
Illustration 44
Throttle pedal assembly
(1) Sensor mounting face
(2) Sensor drive key
(3) Mounting screw holes
Illustration 45
Throttle block assembly
(1) Mounting screw holes
(2) Sensor housing
(3) Sensor drive slot
Illustration 46
Throttle block assembly
(1) Mounting screw holes
(2) Sensor drive slot
(3) Sensor mounting face
A. Verify that the keyswitch is in the OFF position.
B. Note the sensor orientation in the throttle pedal
assembly and the sensor connector for the
harness routing prior to sensor removal. Remove
the digital throttle position sensor from the throttle
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pedal assembly. Thoroughly inspect the connector
and the harness for signs of abrasion.
C. Connect a multimeter that is capable of measuring
a PWM duty cycle to terminal "C" of the breakout
"T".
D. Turn the keyswitch to the ON position.
E. Display the duty cycle output of the digital throttle
position sensor while the sensor slot is released.
Use a screwdriver to advance the sensor slot to
the maximum position. Refer to Illustration 46.
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Troubleshooting Section
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