SENSOR 4875646 - Caterpillar

Unexpected Motion Detected
The following description applies to these event codes (EID) only.
E575 "Unexpected Drive Motor Forward Speed Detected"
E576 "Unexpected Drive Motor Rearward Speed Detected"Higher than expected response from the hystat motor will cause these events to be logged. Significant response in the direction opposite of the expected response from the hystat motor will also cause these events to be logged.Triggering an E575 or E576 will cause the machine to perform an immediate machine shutdown if traveling at speed less than 10 km/h (6 mph), and will stop the machine quicker than an operator can respond to a pump and/or motor failure. Inputs used to measure the difference between the actual travel speed and travel speed commanded by the operator are:
Motor Speed sensor signals
Engine Speed sensor signals
Drive Pressure sensor signalsIf a significant difference is detected for a certain length of time, the machine is brought to a stop quickly. When the difference is detected, the appropriate event code is logged. The keyswitch must be cycled before the event will be cleared and the machine will be allowed to operate.Causes of an Unexpected Motion Detected Event
Noncurrent Machine Software - Earlier machine software could produce "nuisance" uncommanded movement diagnostics (UCMD). Ensure that the current machine flash file is applied.
The Pump Stuck at Maximum Displacement - The motor will be running at the crossover gear ratio when a speed is commanded within the pump range. The machine will not be able to slow down to a stop.
Motor Stuck at Minimum Displacement - The actual speed of the motor will be too high compared to the desired speed of the motor. The drive loop pressure will be excessive while not under load.
Pressure Sensor - If the diagnostic for the drive pressure is active, the pressure defaults to intermediate pressure. A rimpull reduction can cause a false diagnostic to be set.Troubleshooting
Note: Check the hydraulic tank for any debris or contamination. If metal particles are visible, replace the hydraulic oil filter. Use a filter cutter and inspect the particles. Brass or bronze particles can be the result of a pump or motor failure.
Table 1
Troubleshooting for EID codes 0575 and 0576 ONLY
Test Steps Results and Recommended Responses
Before troubleshooting, clear the active E575 or E576 event code. Turn the keyswitch to the OFF Position, wait 5 seconds, turn the keyswitch to the ON Position.
Proceed to step 1.
1. Is there an active hystat drive pressure sensor or solenoid fault?
Relevant Sensor Faults:
CID 3561 = Drive Circuit Forward Pressure Sensor.
CID 3562 = Drive Circuit Reverse Pressure Sensor.
CID 3563 = Drive Motor #1 Solenoid.
CID 3564 = Drive Motor #2 Solenoid. YES - Fix the relevant sensor fault. Refer to Troubleshooting, "Sensor Signal (Analog Active) - Test" or, "Solenoid Valve - Test".
Proceed to Step 2 when complete.
NO - Proceed to test step 2.
2. Is there an active Datalink Fault? YES - Fix the Datalink Fault. Refer to Troubleshooting, "Cat Data Link - Test".
Proceed to test step 3.
NO - Proceed to step 3.
3. Operate the machine. Does a new E575 or E576 event