COVER 4577976 - Caterpillar

tool to perform a "Wiggle Test". If faults are indicated then go to the appropriate procedure. STOPTest Step 4. Disconnect The Sensor In Order To Create An Open Circuit
Turn the keyswitch to the OFF position.
Disconnect the sensor connector of the sensor with the Voltage Below Normal diagnostic code.
Turn the keyswitch to the ON position.Note: Wait at least 10 seconds for activation of the diagnostic codes.
Access the "Active Diagnostic Code" screen of the electronic service tool. Check for an active Voltage Above Normal diagnostic code.Expected Result:A Voltage Above Normal diagnostic code for the disconnected sensor is now active.Results:
OK - A Voltage Below Normal diagnostic code was active before disconnecting the sensor. An Voltage Above Normal diagnostic code became active after disconnecting the sensor.Repair: Perform the following procedure:Replace the sensor.Use the electronic service tool in order to clear all logged diagnostic codes.
Inspect the seals of the connectors for damage. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Connect the sensor and check that the fault is eliminated.
If the fault returns, perform the following procedure:
Temporarily connect a new sensor to the harness but do not install the new sensor in the engine.
Use the electronic service tool to verify that the replacement sensor eliminates the fault.
If the diagnostic code is eliminated, install the replacement sensor.
Use the electronic service tool to clear the logged diagnostic codes.STOP
Not OK - There is a short circuit between the sensor harness connector and the ECM. Leave the sensor disconnected. Proceed to Test Step 6.Test Step 5. Create a Short Circuit Between the Signal and the Common Terminals at the Sensor Harness Connector
Disconnect the suspect sensor connector P100 for the coolant temperature sensor or disconnect P103 for the inlet manifold temperature sensor.
Turn the keyswitch to the ON position.Note: Wait at least 10 seconds for the activation of any diagnostic fault codes.
Fabricate a jumper wire 150 mm (6 inch) long. Crimp a terminal to both ends of the wire.
Monitor the "Active Diagnostic Code" screen on the electronic service tool before installing the jumper wire and after installing the jumper wire.
Install the jumper on the engine harness connector for the suspect sensor, P100 for the coolant temperature sensor and P103 for the intake manifold temperature sensor. Install one end of the jumper at the sensor signal (terminal 1). Install the other end of the jumper at the common connection (terminal 2).Note: Wait at least 10 seconds for activation of the Voltage Below Normal diagnostic code.Expected Result:A Voltage Below Normal diagnostic code is active when the jumper is installed. A Voltage Above Normal diagnostic code is active when the jumper is removed.Results:
OK - The engine harness and the ECM are OK.Repair: Perform the following repair:
Temporarily connect a new sensor to the harness but do not install the new sensor in the engine.
Use the electronic service tool to verify that the replacement sensor eliminates the fault.
If the diagnostic code is eliminated, install the replacement sensor.
Use the electronic service tool to clear the logged diagnostic codes.STOP
Not OK - The Voltage Above Normal diagnostic code remains