DIAPHRAGM 4W1034 - Caterpillar

Illustration 1 g02570176
Connections of the Upshift Switch
This diagnostic code is associated with the Upshift Switch. The Upshift 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 both circuits are open.Possible causes of this diagnostic code are listed:
There is a failure in the harness.
The switch has failed.Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all of the connections in the circuit are clean and secure. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0622 FMI 03 is active before performing this procedure.Note: Use a digital multimeter for the measurements in this procedure.
Table 1
Upshift Switch
Switch Position G760-WH(White) Circuit
N/O J1-41 G768-GN(Green) Circuit
N/C J1-40
Depressed Closed Open
Released Open Closed System Response:Transmission upshifts are disabled.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 switch harness assembly.
Measure the resistance between contact 2 (wire 202-BK(Black)) 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 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 OPERATION OF THE SWITCH IN THE RELEASED POSITION
The machine harness remains disconnected from the switch