CAB GP 1025820 - Caterpillar

Illustration 1 g03099076
Schematic of the transmission controlThis diagnostic code is associated with the transmission direction control switch. The transmission direction control switch is connected to three inputs of the transmission Electronic Control Module (ECM). Two contacts are open and the other contact is grounded during proper operation.This FMI 03 means that the ECM has determined that both circuits have been open for at least 30 seconds.Note: The following test procedure may create other diagnostic codes. Ignore these diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0623 FMI 03 is active before performing this procedure.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 from the joystick harness assembly.
Measure the resistance between contact 2 (wire J764-BR) of the machine harness and frame ground.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 5.
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 OPERATION OF THE SWITCH (NEUTRAL POSITION)
The machine harness remains disconnected from the switch harness assembly.
Move the switch to the neutral position.
Connect one lead from a multimeter to contact 2 (wire J764-BR) of the joystick harness assembly.
Connect the other lead from a multimeter to contact 3 (wire M983-PU) of the joystick harness assembly.
Measure the resistance between contact 2 and contact 3. Note the resistance.
Disconnect the lead from contact 3 and connect the lead to contact 6 (wire C950-BU).
Measure the resistance between contact 2 and contact 6. Note the resistance.Expected Result: