OPERATOR PLATFORM 1337889 - Caterpillar

Operation Description:The following procedure should be performed if the ECM does not turn on. Possible causes of failure are listed below:
Blown fuse for the ECM
Failure in the machine harnessTest Step 1. CHECK FOR A BLOWN FUSE
Locate the fuse for the transmission ECM in the fuse panel of the machine.
Check the condition of the fuse.Expected Result:The fuse is NOT blown.Results:
OK - The fuse is NOT blown. Proceed to test step 4.
NOT OK - The fuse is blown. Proceed to test step 2.Test Step 2. CHECK THE HARNESS
Turn the ignition switch to the OFF position.
Disconnect the machine harness from the ECM.
Measure the resistance between contact 1 and contact 2 at the machine harness connector.Expected Result:The resistance is greater than 5000 ohms.Results:
OK - The resistance is greater than 5000 ohms. The wiring harness is correct. Proceed to test step 3.
NOT OK - The resistance is less than 5 ohms. There is a short to ground in the +battery wire 126-PK for the control.Repair: Repair the harness or replace the harness. Replace the blown fuse in the fuse panel of the machine. Stop.Test Step 3. CHECK THE ECM
The machine harness connector remains disconnected from the ECM.
Measure the resistance between contact 1 and contact 2 of the ECM.Expected Result:The resistance is approximately 5000 ohms.Results:
OK - The resistance is approximately 5000 ohms. The resistance is correct.Repair: Replace the blown fuse in the fuse panel of the machine. Stop.
NOT OK - The resistance is NOT greater than 5000 ohms. The ECM has an internal short.Repair: Replace the ECM. Refer to Testing and Adjusting, "Electronic Control Module - Replace". Replace the blown fuse in the fuse panel of the machine. Stop.Test Step 4. CHECK FOR BATTERY VOLTAGE AT THE ECM
Turn the key start switch to the ON position.
Measure the voltage at the battery terminals of the machine.Note: Make a note of the voltage measurement.
Use the 7X-1710 Multimeter Probe in order to measure the voltage at the harness connector between contacts 1 and 2.Expected Result:The voltage at the harness connector does NOT vary from the battery voltage by more than 0.5 VDC.Results:
OK - The voltage at the harness connector does NOT vary from the battery voltage by more than 0.5 VDC. The system voltage is correct.Repair: Check the operation of the machine. If the machine is not functioning properly, proceed to Troubleshooting, "Using the Diagnostic Indicator to Determine Diagnostic Codes" and Troubleshooting, "Diagnostic Code List". Stop.
NOT OK - The voltage at the harness connector varies from the battery voltage by more than 0.5 VDC. The system voltage is NOT correct. A failure exists in the wiring from the ECM fuse to the ECM or a failure exists in the wiring from the ground stud to the ECM.Repair: Repair the machine harness or replace the machine harness. Stop.