GUIDE-TAP 9M6591 - Caterpillar

Illustration 1 g03800020
Schematic of the Left Joystick Position Sensor
This diagnostic code is associated with the Left Joystick Left/Right Position Sensor. The sensor provides an input signal to the ECM. This diagnostic code is recorded when the ECM determines that the voltage of the signal is above normal. The position sensor is a PWM sensor that operates at a frequency of approximately 500 80 Hz. The duty cycle of the signal will vary. The signal will vary approximately 20% at the joystick in the full rearward position. The signal will vary by approximately 80% at the joystick in the full forward position. When the joystick is in the center position, the duty cycle will be approximately 50%.The possible causes of this diagnostic code are listed:
The sensor for the power supply circuit is open.
The sensor for the return circuit is open.
The signal circuit is open.
The signal circuit is shorted to a voltage source.
The sensor has failed.
The ECM has failed. ECM failure is unlikely. Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all of the connections in the circuit are clean. Verify that all of the connections in the circuit are secure. Verify that all of the connections in the circuit are in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure. Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the problem has been corrected. Verify that CID 2476 FMI 03 is active before performing this procedure.System Response:The diagnostic will generate a level 2 warning. The machine will be brought to a stop and the park brake will be engaged. The park brake will remain engaged until the diagnostic has been cleared and the hystat lever has been returned to the neutral position.Test Step 1. Check The Sensor Power Supply
Turn the key start switch to the ON position.
At the harness connector for the left joystick, insert 7X-1710 Multimeter Probes along the contact for the power supply 1 (wire 126-PK(Pink)) and along ground contact 2 (wire 203-BK(Black)). Do not disconnect the machine harness from the connector for the joystick.
Measure the (12 VDC) battery voltage of the sensor power supply. Expected Result:The (12 VDC) battery voltage measurement is available.Results:
OK - The (12 VDC) battery measurement is correct. Proceed to Test Step 2.
NOT OK - The measurement is not correct. Repair: Either the wire for the sensor ground in the circuit 203-BK(Black) or the supply wire 126-PK(Pink) has a bad connection or an open in the machine harness. Refer to the Electrical System Schematic. Examine all of the connectors that are in the circuit. Verify that all circuit connections are clean. Verify that all circuit connections are secure. Verify that all circuit connections are in good condition. Repair or replace the machine