SEAL-LIP 6V5029 - Caterpillar

System Operation Description:Use this procedure to troubleshoot the electrical system if a problem is suspected with the circuit that is for the throttle position sensor or if one of the diagnostic codes in Table 1 is active or easily repeated.
Table 1
Diagnostic Codes Table    
Code and Description     Conditions which Generate this Code     System Response    
91-8 Throttle Position Sensor abnormal frequency, pulse width, or period     The Electronic Control Module (ECM) detects an incorrect frequency on the throttle signal or an incorrect duty cycle on the throttle signal. The frequency is below 150 Hz or the frequency in above 1000 Hz. The duty cycle is less than 5 percent or the duty cycle is greater than 95 percent.
This code is used when the parameter for the "Desired Speed Input Configuration" is configured to "PWM".     The code is logged. The ECM flags the throttle position as invalid data and a default value of zero percent is used. The engine speed defaults to rated speed.    
1690-8 Throttle #2 Position Sensor abnormal frequency, pulse width, or period     The ECM detects an incorrect value for the throttle signal. The value for the analog input is outside the range of zero to five volts.
This code is used when the parameter for the "Desired Speed Input Configuration" is configured to "0 - 5 VDC".    The throttle position sensor provides the throttle signal to the engine's ECM. The output for rated speed is a pulse width modulated signal (PWM) at a constant frequency. The throttle position sensor produces a minimum duty cycle in the lowest position and a maximum duty cycle in the highest position of the sensor. When the sensor is in the lowest position, the ECM translates the sensor's output signal to a throttle position of 0 percent. When the sensor is placed in the highest position, the ECM translates the output signal to a throttle position of 100 percent.The ECM uses an automatic calibration function that allows the ECM to maximize the usable range of the sensor. The automatic calibration function assumes a range of PWM duty cycle at powerup. If the duty cycle of the sensor exceeds this initial range, the automatic calibration function adjusts the limits of the duty cycle in order to adjust for the new range.This application can also be equipped with a load sharing module. The load sharing module provides a throttle signal to the ECMin place of the throttle position sensor. The output of the load sharing module allows multiple generators to share the load equally. The speed signal from the load sharing module 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.The ECM calculates the desired engine rpm from the throttle signal. The throttle signal is valid when the duty cycle is in the range of 5 to 95 percent. If the ECM determines that the throttle signal is invalid,