CARRIER 3795468 - Caterpillar

Illustration 1 g02568439
Schematic of the push-button switch (Cushion-Hitch)This diagnostic code is associated with the Push Button Switch (Cushion-Hitch). The switch is connected to two inputs of the ECM. One contact is open and the other contact is grounded during proper operation.This FMI 03 means that the ECM has determined that the normally open contact and the normally closed contact are open.Note: The following test procedure may create other diagnostic codes. Ignore these diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 1293 FMI 03 is active before performing this procedure.System Response:When this diagnostic code occurs, a warning (Category 1) is shown on the monitor. The diagnostic code will cause the function that is controlled by the push switch to be inoperative. The function will remain in the last state. If the last state was ON, the state will stay ON. When the power is cycled on the ECM, the state goes OFF and the state cannot be turned ON.Test Step 1. CHECK THE GROUND CIRCUIT OF THE SWITCH IN THE HARNESS
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connector(s) from the ECM.
Measure the resistance between contact J2-22 (wire J766-PU) of the machine harness for the Transmission ECM and contact 5 (wire J766-PU) at the switch.Expected Result:The resistance is less than 5 ohms.Results:
OK - The resistance is less than 5 ohms. The circuit is correct. Proceed to Test Step 2.
NOT OK - The resistance is greater than 5000 ohms. The circuit is open. The machine harness has failed.Repair: Repair the machine harness or replace the machine harness.STOPTest Step 2. CHECK THE SWITCH CIRCUITS FOR A SHORT TO THE +BATTERY CIRCUIT
The machine harness connector(s) remains disconnected from the ECM.
The disconnect switch and the key start switch remain in the OFF position.
Disconnect contact 8 (wire R756-WH) and contact 9 (wire R757-BR) from the connector of the switch.
At the machine harness connector for the ECM, measure the resistance from contact 8 (wire R756-WH) and contact 9 (wire R757-BR) of the machine harness to all the contacts that are used in the machine harness connectors for the ECM.Expected Result:Each resistance measurement is greater than 5000 ohms.Results:
OK - Each resistance measurement is greater than 5000 ohms. The harness is correct. Proceed to Test Step 3.
NO - One or more of the measurements were less than 5 ohms. There is a short in the machine harness.Repair: The short is between wire R756-WH and the circuit with the lowest resistance measurement or the short is between wire R757-BR and the circuit with the lowest resistance measurement. Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK THE SWITCH CIRCUITS IN THE HARNESS
The machine harness remains disconnected from the ECM and the switch.
At the harness connector for the switch, connect a jumper wire between contact 8 (wire R756-WH) and contact 9 (wire R757-BR).
At the harness connector for the ECM, measure the resistance from contact J1-63