BEARING-SLEEVE 7T9014 - Caterpillar

System Operation Description:Use this procedure to troubleshoot the electrical system if a problem is suspected with the speed control or if the diagnostic code in Table 1 is active or easily repeated.
Table 1
Diagnostic Codes Table    
Code    Conditions which Generate this Code    System Response    
91-8 Throttle Position Sensor : Abnormal Frequency, Pulse Width, or Period     The Engine's Electronic Control Module (ECM) detects a sensor frequency that is less than 150 Hz or a sensor frequency that is greater than 1000 Hz for two seconds.
or
The ECM detects a duty cycle that is less than 5 percent or a duty cycle that is greater than 95 percent for one second.     The code is logged.
The throttle signal defaults to a zero percent duty cycle (low idle).    The speed control is used to provide a throttle signal to the engine control. The output for rated speed is a pulse width modulated signal. The signal varies with the position of the speed adjust potentiometer. The output signal is expressed as a percentage between 0 and 100 percent for the speed adjust potentiometer.The ECM calculates the desired engine speed. The desired engine speed is produced by the signal from the rated speed setting. The rated speed signal is valid when the duty cycle is in the range of 5 to 95 percent. If the rated speed signal is invalid, the engine will be set to the low idle.Some applications may choose not to use the speed control. Some applications may use a load sharing unit. The unit is configured to provide the engine control with a rated speed signal. Some of these units cannot provide a signal until the engine is running. In these cases, perform troubleshooting while the engine is running.
Illustration 1 g01384189
Typical schematic
Illustration 2 g01384192
P1 ECM connector (P1-10) Throttle
Illustration 3 g01384194
Customer connector (Terminal 66) Throttle
Illustration 4 g01234146
Location of ECM connectorsTest Step 1. Inspect Electrical Connectors and Wiring
Turn the main disconnect switch to the OFF position.
Thoroughly inspect the ECM connector J1/P1. Inspect the customer connector. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the circuit.
Check the harness and the wiring for abrasion and for pinch points.Expected Result:The components and wiring are free of the following problems: damage, corrosion, abrasion and incorrect attachment.Results:
OK - The wiring and connectors are OK. Proceed to Test Step 2.
Not OK - The wiring and/or connectors need repair.Repair: Repair the connectors or wiring and/or replace the connectors or wiring.STOPTest Step 2. Check the Voltage at the Speed Control
Turn the main disconnect switch to the ON position.
Connect the red probe of the digital multimeter to the +Battery terminal of the speed control. Connect the black probe of the digital multimeter to the −Battery terminal of the speed control.Expected Result:The digital multimeter reads 24 3 VDC.Results:
OK - The