LIGHTING SYSTEM GROUP 1S2306 - Caterpillar

Illustration 3 g01185326
Typical throttle assembly (1) Sensor mounting face (2) Sensor drive key (3) Mounting screw holes
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Throttle block assembly (1) Mounting screw holes (2) Sensor housing (3) Sensor drive slot
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Throttle block assembly (1) Mounting screw holes (2) Sensor drive slot (3) Sensor mounting face
Verify that the keyswitch is in the OFF position.
Note the sensor orientation in the throttle assembly and the sensor connector for the harness routing prior to sensor removal. Remove the digital throttle position sensor from the throttle assembly. Thoroughly inspect the connector and the harness for signs of abrasion.
Connect a multimeter that is capable of measuring a PWM duty cycle to terminal "C" of the breakout "T".
Turn the keyswitch to the ON position.
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 5.Expected Result:When the sensor is removed from the throttle assembly and the sensor slot is released, the duty cycle is 10 percent or less. When the sensor slot is moved to the maximum position, the duty cycle increases to 90 percent or more.Results:
OK - The digital throttle position sensor is working correctly. Refer to the OEM dealer for correct replacement of the throttle assembly. STOP
Not OK - The digital throttle position sensor is faulty. Check the throttle assembly in order to ensure that the throttle assembly is not causing damage to the sensor. If the throttle assembly is causing damage to the sensor, refer to the OEM dealer for correct replacement of the throttle assembly. If the throttle assembly appears OK, replace the digital throttle position sensor.STOPTest Step 11. Route the Supply Bypass Wires to the Digital Throttle Position Sensor
Turn the keyswitch to the OFF position.
Temporarily remove the signal wire for the digital throttle position sensor from P1:53.
Remove terminal "C" (digital throttle position sensor signal) from the digital throttle position sensor connector.
Route the new wiring from the ECM to the digital throttle position sensor.
Turn the keyswitch to the ON position.
Check the duty cycle of the digital throttle position sensor on the electronic service tool while the digital throttle assembly is being moved over the full range.Expected Result:The duty cycle is between 10 and 22 percent with the throttle assembly in the low idle position, and the duty cycle is between 75 and 90 percent with the throttle assembly in the high idle position.Results:
OK - Repair: Perform the following repair:The wiring from the ECM to the digital throttle position sensor appears faulty. Permanently install new wiring.Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.STOP
Not OK - Double check the wiring, the P1/J1 connectors and the digital throttle position sensor connector. If a fault still exists, repeat the test procedure from Test Step 1.STOP