FLANGE-JOINT 1T0364 - Caterpillar

System Operation Description:Use this procedure under the following situation:Use this procedure to determine if the service brake pedal position (switch 1) is operating properly.Service Brake Pedal Position (Switch 1)The switch for the service brake pedal position (switch 1) is normally closed when the respective pedal is released. Depressing the brake pedal should open the individual circuit. This switch is OEM supplied. The service brake pedal position (switch 1) is typically a pressure switch.This switch may not be connected to an input on the Engine Control Module (ECM). The parameter "Service Brake Pedal Position Switch 1" determines the input to the ECM. If the parameter is programmed to "J1/P1:45" a switch must be connected to terminal 45. If the parameter is programmed to one of the J1939 options, the switch position will be transmitted to the ECM over the J1939 data link. If a problem is suspected with the J1939 data link, refer to Troubleshooting, "Powertrain Data Link Circuit - Test".
Illustration 1 g00864414
Typical circuit schematic for the service brake pedal position (switch 1)The return wire may be connected to P1-3, P1-5, or P1-18.Test Step 1. Inspect Electrical Connectors and Wiring.
Illustration 2 g01152482
Pin locations on ECM connector (P1-5) AP sensor/switch sensor common (P1-45) Service brake pedal position switch
Thoroughly inspect ECM vehicle harness connector J1/P1, the firewall bulkhead connector and the terminals for the following switches in the connectors:
Terminal 5 (AP Sensor/Switch Sensor Common )
Terminal 45 (Service Brake Pedal Position (Switch 1))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 switches.Refer to Illustration 2.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and wiring for abrasion and pinch points from the sensor to the ECM.Expected Result:All connectors, pins and sockets are completely coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion or of pinch points.Results:
OK - Proceed to Test Step 2.
Not OK - Repair: Perform the following repair:Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem.STOPTest Step 2. Check the Status of the Service Brake Switch on Caterpillar Electronic Technician (ET)
Table 1
Table for Status of the Service Brake Pedal Position    
Switch Position or Pedal Position    Status    Circuit    
The service brake pedal is depressed.     OFF     Open    
The service brake pedal is released.     ON     Closed    
Access the Cat ET status screen.
Turn the ignition key switch to the ON position.
Depress the service brake while the status of the service brake pedal position (switch 1) is being observed. Also, release the service brake while the status of the service brake pedal position (switch 1) is being observed.Refer to Table 1 for the status of the switch or for the status of the