V-BELT 2803790 - Caterpillar

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The "Park Brake Pressure" Switch is located on the park brake housing on the engine side of the transmission.
(1) "Park Brake Pressure" Switch
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"Park Brake Pressure" Switch connections
This diagnostic code is associated with the "Park Brake Pressure" switch. The switch supplies two inputs to the "Transmission/Chassis ECM". The switch allows the ECM to detect whether the parking brake is applied or the parking brake is not applied. The ECM expects the two switch inputs to be connected through the switch contacts when the parking brake is applied. The ECM expects the normally open (N/O) contact to be grounded when the park brake is not applied. When the ECM detects that the switch inputs are not connected and the N/O contact is not grounded, the ECM will activate an FMI 03 diagnostic code for voltage above normal.Possible conditions that can cause this diagnostic code are listed below:
One or both of the switch circuits are open in the machine harness.
The ground circuit is open in the machine harness.
The switch has failed.
The ECM has failed. A failure of the Tranmsission/Chassis ECM is unlikely.Note: Ensure that all safety information, warnings, and instructions are read and understood before any operation or procedures are perfromed. Perfrom the following safety measures before you begin to troubleshoot the machine:
Move the machine to a surface that is hard and level.
Lower all of the implements to the ground.
Toggle the parking brake switch to the ON position.
Place chocks in the front of the wheels and behind the wheels.
Shut off the engine.Note: 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 connections in the circuit are clean, that all connections are secure and that all connections 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.
Table 1
Contact states of the "Park Brake Pressure" Switch
Park Brake Status N/O Input J1-35 (wire R736-PK(Pink)) N/C Input J1-40 (wire C491-PU(Purple))
Applied Open Grounded
Not Applied Grounded Open
Short-to-Battery Open Open Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Test Step 1. CHECK THE INPUT CIRCUITS OF THE SWITCH FOR AN OPEN
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the machine harness connector from the switch.
At the machine harness connector for the switch, connect a jumper wire between the normally open (N/O) contact B (wire R736-PK(Pink)) and the normally closed (N/C) contact C (wire C491-PU(Purple)).
Disconnect the machine harness connector J1 from the Transmission/Chassis ECM.
At the machine harness connector for the "Transmission/Chassis ECM", J1, measure the resistance between N/C contact J1-40 (wire C491-PU(Purple)) and N/O contact J1-35 (wire R736-PK(Pink)). Expected Result:The resistance measurement is less than 5 ohms.Results:
OK - The resistance measurement is less than 5 ohms. The input circuits of the switch are