ELBOW 2474806 - Caterpillar

Illustration 1 g00438565
Schematic for the Rocker Switch (Transmission Direction)The transmission direction switch has three inputs to the power train electronic control module (ECM). During normal operation, two of the inputs are open and the other input is grounded. This diagnostic code is detected when all of the inputs are open or shorted to the +battery. Before you perform this procedure use table 1 in order to determine the connector and the contacts that correspond to the faulty circuit. The fault is set in 30 seconds and the fault is cleared in one second.
Table 1
Status of Direction Switch    
Switch Position    G755-GY Circuit
R Switch
J1-14    G763-PU Circuit
N Switch
J1-13    G750-BU Circuit
F Switch
J1-30    
R     Closed     Open     Open    
N     Open     Closed     Open    
F     Open     Open     Closed    Note: Ensure that the desired fault is active.Note: The following procedure can create other faults that may be detected by the power train ECM. Ignore these created faults and clear the created faults when the diagnostic code is corrected.Possible causes of the diagnostic code are listed:
There is a harness fault.
There is a failed switch.System Response:The machine response is listed:
The transmission will lock in neutral until a valid neutral switch position is sensed.Test Step 1. CHECK FOR AN OPEN CIRCUIT.
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the machine harness connector J1 from the power train ECM.
At the machine harness connector for the power train ECM, check the continuity to ground of the switch contacts for the transmission direction switch that is activated and switch that is not activated. Refer to table 1 for the correct status of the transmission direction switch.Expected Result:The continuity check does NOT agree with table 1.Results:
YES - The continuity check does NOT agree with the previous table. The harness or the transmission direction switch is faulty. Proceed to Test Step 2.
NO - The continuity check agrees with the previous table. Proceed to Test Step 3.Test Step 2. CHECK THE TRANSMISSION DIRECTION SWITCH.
Disconnect the machine harness from the transmission direction switch.
Check the continuity to ground of the switch contacts for the transmission direction switch that is activated and switch that is not activated. Refer to table 1 for the correct status of the transmission direction switch.Expected Result:The continuity check does NOT agree with table 1.Results:
YES - The continuity check does NOT agree with the previous table. The transmission direction switch is faulty.Repair: Repair the switch or replace the switch. Stop.
NO - The continuity check agrees with the previous table.Repair: Repair the machine harness or replace the machine harness. Stop.Test Step 3. CHECK FOR A SHORT TO THE +BATTERY.
At the machine harness connector J1 for the power train ECM, check the continuity between the wire for the switch contact and the following contacts: J1-1, J1-6, J1-40 and J2-12.Expected Result:Continuity exists between one of the sources of the battery voltage and the switch circuit.Results:
YES - Continuity exists between one of the sources of battery voltage. The