0318816 JOHNSON PLUG,Exhaust hsg.

Illustration 1 g02265653
Schematic for the 834G Wheel Tractor (BPC), 836G Landfill Compactor (BRL), and 988G Wheel Loader (BNH)Schematic for the 814F Wheel Dozer (BGF), 815F Soil Compactor (BKL), and 816F Landfill Compactor (BMR)
Illustration 2 g02271513
Schematic for the 814F Wheel Dozer (BGF), 815F Soil Compactor (BKL), and 816F Landfill Compactor (BMR)Schematic for the 824G II Wheel Tractor (AWW), 950G II Wheel Loader (AYB), and 826G II Landfill Compactor (AYH)
Illustration 3 g02265676
Schematic for the 824G II Wheel Tractor (AWW), 950G II Wheel Loader (AYB), and 826G II Landfill Compactor (AYH)Test Step 1. Inspect Electrical Connectors and Wiring
Remove the electrical power from the ECM.
Thoroughly inspect the J1/P1 ECM connector. Thoroughly inspect the connector for the engine shutdown switch. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect".
Check the ECM connector (allen head screw) for the proper torque. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and the wiring for abrasion and for pinch points.Expected Result:All of the connectors, pins, and sockets are coupled and/or inserted. The harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The harness and connectors appear to be OK. Proceed to Test Step 2.
Not OK - The connectors and/or wiring are not OK.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 coupled.Verify that the repair eliminates the problem.STOPTest Step 2. Check the Switch Status on Cat ET
Connect Cat ET to the service tool connector.
Restore the electrical power to the ECM.
Observe the status for "Shutdown Switch" on Cat ET while you operate the engine shutdown switch.
Remove the electrical power from the ECM.Expected Result:The status is "On" with the switch in the STOP position. The status is "Off" with the switch in the RUN position.Results:
OK - The switch is operating normally.Repair: Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" if an intermittent electrical problem is suspected.STOP
Not OK - The status of the shutdown switch is incorrect. Proceed to Test Step 3.Test Step 3. Short the Wires at the Switch
Disconnect the connector for the engine shutdown switch.
At the switch connector, install a jumper wire between the pin for Engine Shutdown Switch (NC)and the pin for Digital Sensor Return.
Restore the electrical power to the ECM and observe the status for "Shutdown Switch" on Cat ET.The status should be "Off".
Remove the electrical power from the ECM.
Remove the jumper wire.
At the switch connector, install the jumper wire between the pin for Engine Shutdown Switch (NO)and the pin for Digital Sensor Return.
Restore the electrical power to the ECM and observe the status for "Shutdown Switch" on Cat ET.The status should be "On".
Remove the electrical power from the ECM.
Remove the jumper wire.Expected Result:The status is "Off" with the jumper wire between the pin for Engine Shutdown Switch (NC) and the pin for Digital Sensor Return. The status changes to "On" with the jumper wire between the pins for Engine Shutdown Switch (NO) Digital Sensor Return.Results:
OK - The wiring from the connector to the ECM is OK. There is a problem with the switch.Repair: Temporarily connect a new switch. Verify that the new switch solves the problem before you permanently install the new switch.STOP
Not OK - The ECM did not detect the shorts. There is a problem in the harness and/or the ECM. Proceed to Test Step 4.Test Step 4. Short the Switch Inputs at the ECM
Remove the electrical power from the ECM.
Install a 208-0059 Adapter Cable As (70-PIN BREAKOUT) at the J1/P1 ECM connector.
Install a jumper wire between the pin for Engine Shutdown Switch (NC) and the pin for Digital Sensor Return at the breakout.
Restore the electrical power to the ECM and observe the status for "Shutdown Switch" on Cat ET.The status should be "Off".
Remove the electrical power from the ECM.
Remove the jumper wire from the breakout.
Install the jumper wire between the pin for Engine Shutdown Switch (NO) and the pin for Digital Sensor Return at the breakout.
Restore the electrical power to the ECM and observe the status for "Shutdown Switch" on Cat ET.The status should be "On".
Remove the electrical power from the ECM.Expected Result:The status is "Off" with the jumper wire between the pin for Engine Shutdown Switch (NC) and the pin for Digital Sensor Return. The status changes to "On" with the jumper wire between the pins for Engine Shutdown Switch (NO) and Digital Sensor Return.Results:
OK - The ECM properly reads the inputs for the shutdown switch at the ECM connector P1 but not at the connector for the switch.Repair: The wiring harness is faulty. Repair the wiring harness. Verify that the repair eliminates the problem.STOP
Not OK - The ECM is not reading the inputs for the shutdown switch properly.Repair: Verify your results.Replace the ECM. Refer to electronic troubleshooting Troubleshooting, "Replacing the ECM" before replacing the ECM.STOP