PLATE 1076547 - Caterpillar

Transmission ECM
The following is a list of Diagnostic Trouble Codes (DTCs) that are associated with the ECM Location Code circuits of the machine.
Table 1
Transmission ECM (MID 81)
DTC Code Description System Response
1326-2 ECM Location Code: Data Erratic, Intermittent, or Incorrect The Transmission ECM will be disabled. The ECM location code is defined by wires going from the ECM location code pins on the ECM to ground. The combination of wires connected to ground corresponds with the software on the ECM. If the incorrect wires are connected to ground, or the incorrect version of the ECM software is installed a 1326-2 diagnostic code will occur.Possible causes of an FMI 2 Diagnostic code are:
The wires for the location code are open or the wires are shorted.
The wrong software is installed on an ECM.
Illustration 1 g03655438
Schematic of the ECM Location Code circuits
Note: The diagram above is a simplified schematic of the connections for the ECM Location Code circuits. The schematic is electrically correct. However, not all of the possible harness connectors are shown. Refer to the latest revision of the Electrical Schematic, UENR3832 for the complete schematic.Diagnostic Trouble Code Procedure
Note: Prior to beginning this procedure, inspect the harness connectors that are involved in this 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 the diagnostic code is active before performing a troubleshooting procedure. For sensors powered via the fuse panel, check the condition of the appropriate fuse before beginning the troubleshooting procedure.
Table 2
Troubleshooting Test Steps Values Results
1. Verify The Hardware And The Software Part Numbers
A. Using "WinFlash" check that the latest software for each ECM corresponds with the correct location code. Check with your dealer for the latest software part numbers.
B. The part number of the flash software for each ECM.
C. The part number of the Switch Panel.
D. The part number of each ECM. All part numbers are correct. OK - All part numbers are correct, proceed to test Step 2.
NOT OK - None of the ECMs show any of the location codes listed. There is a problem with the machine harness.
Repair: Repair or replace the machine harness.
NOT OK - All part numbers are NOT correct. The installed ECM has the wrong part number or incorrect configuration software is installed.
Repair: Flash the correct configuration software on the ECM with the displayed location code. Refer to Troubleshooting, "ECM Software - Install". Prior to replacing an ECM, always contact the Technical Communicator for your dealership for possible consultation with Caterpillar. This consultation may greatly reduce repair time.
See the Troubleshooting, "ECM - Replace" section of this manual for additional information.
STOP
2. Inspect The Harness Connections
A. Turn the disconnect switch to the OFF position.
B. Inspect all harness connections that are related to the location codes. Make sure that the connectors are clean and tight.
C. Check the connectors for proper mating. Ensure that all the