SHEET ASSEM. 5V3728 - Caterpillar

Illustration 1 g01428132
Schematic for the Left Conveyor Master Switch of the Implement ECM for the AS4251C ScreedThis diagnostic code is associated with the Left Conveyor Master Switch. The FMI 02 means that the ECM determined that the signal is intermittent, erratic, or incorrect. The ECM could be receiving invalid combinations from the circuit.System Response:When this diagnostic code is active, the following occurs:
Switch defaults to the automatic mode.
Operator station fault lamp is active.Note: The Implement (Screed) ECM is located under the Screed Platform. Test Step 1. CHECK THE CONTINUITY OF THE SWITCH IN THE OFF (CENTER) POSITION
Turn the key start switch to the OFF position.
Remove the switch from the dash.
Unplug the switch from the wire harness.
With the switch in the OFF (Center) position, check the resistance from terminal 2 to the following terminals: terminal 1 and terminal 3.Expected Result:The resistances should be greater than 5000 ohms.Results:
OK - The resistances are greater than 5000 ohms. Proceed to Test Step 2.
NOT OK - The resistance is less than 5000 ohms on one of the readings.Repair: The switch has failed. Replace the switch.STOPTest Step 2. CHECK THE CONTINUITY OF THE SWITCH IN THE MANUAL POSITION
Press and hold the switch in the MANUAL position.
With the switch in the MANUAL position, check the resistance from terminal 2 to terminal 1 and to terminal 3.Expected Result:The resistance should be less than 5 ohms on terminals 1 and 2. The resistance should be greater than 5000 ohms on terminals 2 and 3.Results:
OK - The resistances are correct. Proceed to Test Step 3.
NOT OK - The resistance is not less than 5 ohms from terminal 1 to terminal 2 or the resistance is not greater than 5000 ohms from terminal 3 to terminal 2.Repair: The switch has failed. Replace the switch.STOPTest Step 3. CHECK THE CONTINUITY OF THE SWITCH IN THE REVERSE POSITION
Press and hold the switch in the REVERSE position.
With the switch in the REVERSE position, check the resistance from terminal 2 to terminal 1 and to terminal 3.Expected Result:The resistance should be less than 5 ohms from terminal 3 to terminal 2. The resistance should be greater than 5000 ohms from terminal 1 to terminal 2.Results:
OK - The resistances are correct. Proceed to Test Step 4.
NOT OK - The resistance is not less than 5 ohms from terminal 3 to terminal 2 or the resistance is not greater than 5000 ohms from terminals 2 to terminal 1.Repair: The switch has failed. Replace the switch.STOPTest Step 4. CHECK THE HARNESS
The disconnect switch and the key start switch remain in the OFF position.
The machine harness remains disconnected from the switch.
Disconnect the J1 and J2 machine harness connectors from the ECM.
Measure the resistance from contact J1-27 (wire C835-GN) of the machine harness to all the contacts that are used in machine harness connectors for the ECM.
Measure the resistance from contact J1-28 (wire K722-YL) of the machine harness to all the contacts that are used in machine harness connectors for the ECM.Expected Result:Each resistance measurement is greater than 5000 ohms.Results:
YES