HOUSING AS-REAR AXLE 1312529 - Caterpillar

Illustration 1 g01060794
Schematic of the Transmission Auto/Manual SwitchThis diagnostic code is associated with the Transmission Auto/Manual switch. This switch has two inputs to the ECM: normally open (wire 977-YL) and normally closed (wire 973-BR). During normal operation, one switch input is open and the other input is grounded. If each input is in the same state, the ECM will detect a diagnostic code. This diagnostic code is detected when both switch inputs are open at the same time.The possible causes of this diagnostic code are listed:
Short to the + battery terminal.
The circuit is open.
A failed switch
The ECM may have failed. The failure of an ECM is unlikely.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 0368 FMI 03 is active before performing this procedure.Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.Note: 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 connections in the circuit are clean, secure, and in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure. System Response:The autoshift is disabled.Test Step 1. CHECK THE CIRCUIT FOR THE SWITCH.
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the J1 machine harness connector from the ECM.
At the J1 machine harness connector, measure the resistance from contact J1-26 (wire 977-YL) to contact J1-45 (wire J764-BR) with the switch in the Manual position.
At the J1 machine harness connector, measure the resistance from contact J1-26 (wire 977-YL) to contact J1-45 (wire J764-BR) with the switch in the Auto position.
At the J1 machine harness connector, measure the resistance from contact J1-27 (wire 973-BR) to contact J1-45 (wire J764-BR) with the switch in the Manual position.
At the J1 machine harness connector, measure the resistance from contact J1-27 (wire 973-BR) to contact J1-45 (wire J764-BR) with the switch in the Auto position.Expected Result:The resistance should measure less than 5 ohms in one switch position. The resistance should measure greater than 5000 ohms for the other switch position.Results:
YES - The resistance is correct for each measurement. Proceed to test step 3.
NO - The resistance measurement is greater than 5000 ohms for both measurements. The harness or the switch has failed. Proceed to test step 2.Test Step 2. CHECK FOR A SHORT.
Disconnect the switch from the harness.
At the J1 machine harness connector, measure the resistance from contact J1-26 and contact J1-27 to all other J1 and J2 contacts.Expected Result:The resistance measurement should be greater than 5000 ohms for each measurement.Results:
OK - The resistance measurement is greater than 5000 ohms for each measurement.Repair: Replace the switch. Proceed to Test Step 3.
NOT OK - The resistance measurement is not greater than 5000 ohms for one or