0321692 JOHNSON GROMMET

Illustration 1 g00932431
Circuit schematic for the service brake pedal position (switch 2)
Test Step 1. Inspect Electrical Connectors and Wiring
Illustration 2 g01152483
Pin locations for the ECM connector
(P1-64) Input 13 (service brake pedal position switch 2)
Thoroughly inspect ECM vehicle harness connector J1/P1, the firewall bulkhead connector and the terminal P1-64 (service brake pedal position (switch 2)). 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 Pedal Switch 2 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 status screen on Cat ET.
Turn the ignition key switch to the ON position.
Start the engine. Ensure that the air system is charged if the vehicle is equipped with air brakes. Depress the service brake while the status of the service brake pedal position (switch 2) is being observed. Also, release the service brake while the status of the service brake pedal position (switch 2) is being observed. Refer to Table 1 for the status of the switch or for the status of the pedal position.Note: If the status indicates "Not Installed", check the programming of the "Transmission Style". This parameter must be programmed to "Automatic Option 2", "Automatic Option 3", "AT/MT/HT Option 2", or "AT/MT/HT Option 3".Expected Result:The switch status changes per the information in Table 1.Results:
Yes - The switch is operating normally.STOP
No - The ECM is not reading the switch status change. Proceed to Test Step 3.Test Step 3. Check the Switch Circuit
Table 2
Table for Status of Service Brake Pedal Position (Switch 2)
Condition of Switch Circuit Switch Status Circuit
Terminal 64 is open. ON Open
Terminal 64 connected to terminal 5. OFF Closed
Turn the ignition key switch to the OFF/RESET position.
Fabricate a jumper wire 100 mm (4 inch) long. Crimp a Deutsch pin to both ends of the wires.
Disconnect vehicle harness connector P1 from the ECM.
Connect a breakout T to ECM connector J1 and connect P1 to the breakout T.
Install the jumper into terminal 64 (service brake pedal position switch 2) of the breakout T. Connect the other end of the jumper to ECM connector P1-52 (unswitched +Battery) of the breakout T.
Turn the ignition key switch to the ON position.
Verify that Cat ET is connected to the data link connector.
Access the status screen of Cat ET.
While the status of the service brake pedal position (switch 2) is being monitored on the Cat ET status screen, slowly remove the jumper from terminal 52 (unswitched +Battery). Now, slowly insert the jumper into the terminal 52 (unswitched +Battery). Refer to Table 2.Expected Result:The switch status changes per the information in Table 2.Results:
Yes - The ECM is functioning properly. Proceed to Test Step 4.
No - The ECM is not functioning properly.Repair: Perform the following repair:
Temporarily connect a test ECM.
Remove all jumpers and replace all connectors.
Recheck the system for active diagnostic codes.
Repeat the test step.
If the problem is resolved with the test ECM, reconnect the suspect ECM.
If the problem returns with the suspect ECM, replace the ECM.
Verify that the repair eliminates the problem. STOPTest Step 4. Insert a Jumper at the Service Brake Pedal Position (Switch 2)
Table 3
Table for Status of the Service Brake Pedal Position (Switch 2)
Condition of Switch Circuit Switch Status Circuit
The wires to the service brake pedal position switch 2 are disconnected. OFF Open
The wires to the service brake pedal position switch 2 are connected. On Shorted
Turn the ignition key switch to the OFF/RESET position.
Ensure that ECM vehicle harness connector J1/P1 is connected.
Find the switch for the service brake pedal position (switch 2) in the vehicle.
Disconnect the wires from the switch terminals.
Turn the ignition key switch to the ON position.
Verify that Cat ET is connected to the data link connector.
Access the status screen on Cat ET.
While the switch status is being monitored on the Cat ET status screen, slowly connect the switch wires and slowly disconnect the switch wires. Refer to Table 3.Expected Result:The switch status changes per the information in Table 3.Results:
Yes - The switch status changes.Repair: Perform the following repair:Replace the faulty switch.Verify that the repair eliminates the problem.STOP
No - The switch status does not change. There is a problem in the harness between the switch and the ECM. Proceed to Test Step 5.Test Step 5. Insert a Jumper at the Bulkhead Connector