ROD 9R4464 - Caterpillar

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P1 ECM connector (P1-4) 8 VDC supply (P1-5) Digital return (P1-66) Throttle position (P1-68) Secondary throttle position
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Terminals on the machine connector (Terminal 8) 8 VDC supply (Terminal 9) Digital return (C15) (Terminal 10) Throttle (Terminal 11) Secondary throttle C15) (Terminal 15) Digital return (C11) (Terminal 38) Secondary throttle C11)
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J403/P403 for the throttle position sensor (A) 8 V supply (B) Digital return (C) Throttle position
Perform a 45 N (10 lb) pull test on each of the wires in the circuit.
Check the allen head screw from each ECM connector for the proper torque. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" for the correct torque value.
Check the harness and the wiring for abrasion and for pinch points.Expected Result:All of the connectors, pins and sockets are completely coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The harness and connectors appear to be OK. Proceed to Test Step 2.
Not OK - The connectors and/or wiring are not OK.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem.STOPTest Step 2. Inspect the Throttle Pedal Assembly
Inspect the throttle pedal assembly for components that are loose, bent, missing, or worn.
Slowly depress the pedal and release the pedal.Expected Result:The throttle pedal assembly operates smoothly without excessive drag. The pedal springs back smoothly to the low idle position without assistance.Results:
OK - The throttle pedal assembly functions properly. Proceed to Test Step 3.
Not OK - The throttle pedal assembly is in poor repair.Repair: Repair the throttle pedal assembly or replace the throttle pedal assembly, as required.STOPTest Step 3. Check the Status for "Throttle Position"
Connect the Caterpillar Electronic Technician (ET) to the service tool connector.
Restore the electrical power to the ECM.
Observe the status for "Throttle Position" on Cat ET while you operate the throttle pedal through the entire range of travel.Expected Result:The status is zero percent when the throttle pedal is released. The status progressively increases to 100 percent when the throttle pedal is fully depressed.Results:
OK - The throttle position sensor is working properly.Repair: There may be an intermittent electrical problem with the harness or the connectors. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - The throttle position that is displayed on Cat ET does not correspond to the movement of the throttle pedal. Proceed to Test Step 4.Test Step 4. Check the Supply Voltage at the Sensor
Disconnect the connector for the throttle position sensor.
Restore the electrical power to the ECM.
Measure the voltage across terminal A (8 V supply) and terminal B (digital return) on the harness side of the connector.
Remove the electrical power from the ECM.Expected Result:The supply voltage measures 8.0 0.4 VDC at the sensor connector.Results:
OK - The correct voltage is measured at the sensor connector. The sensor is receiving the correct supply voltage. Proceed to Test Step