LATCH AS 6W8906 - Caterpillar

ECM Mode" is a feature in the software that can be used to help troubleshoot an engine that may have a fault in the Electronic Control Module (ECM). This feature allows a standard ECM to be used as a test ECM. This feature eliminates the need to stock a test ECM.
Search for the latest flash file for the engine.Note: If a newer software version is available for the engine, install the newest software on the suspect ECM. If the new software does not eliminate the fault, continue with this procedure.
Use the "Copy Configuration" feature on the electronic service tool to copy the parameters from the suspect ECM.Note: If the "ECM Replacement" feature cannot be used, record the programmed values into the "Parameters Worksheet". Also record the system configuration parameters.
Disconnect the suspect ECM. Temporarily connect the test ECM to the engine. Do not mount the test ECM on the engine.
Flash program the test ECM with the newest software that is available.
Start the "Test ECM Mode" on the electronic service tool. Access the feature through the "Service" menu. The electronic service tool will display the status of the test ECM and the hours that are remaining for the "Test ECM Mode".Note: "Test ECM Mode" can only be activated if the engine serial number has not already been programmed during normal operation of the ECM. If the engine serial number is programmed and the ECM is not in "Test ECM Mode", the ECM can never be used as a test ECM.
Use the "Copy Configuration" feature on the electronic service tool to program the test ECM.Note: If the "ECM Replacement" feature cannot be used, program the test ECM with the values from the "Parameters Worksheet" and the values from the Configuration Parameters.
Program the engine serial number into the test ECM.Note: The "Test ECM Mode" must be activated before the engine serial number is programmed into the ECM.
Verify that the test ECM eliminates the fault.When the "Test ECM Mode" is activated, an internal timer sets a 24 hour clock. This clock will count down only while the ECM is powered and the keyswitch is in the ON position. After the ECM has counted down the 24 hour period, the ECM will exit the "Test ECM Mode". The parameters and the engine serial number will be set.If the test ECM eliminates the fault, the engine can be released while the "Test ECM Mode" is still active.Once an ECM has been activated in the "Test ECM Mode", the ECM will stay in the "Test ECM Mode" until the timer times out. Anytime prior to the "Test ECM Mode" timing out, the "Test ECM Mode" can be reset to 24 hours. If the ECM is used as a test ECM for more than one engine, reactivate the "Test ECM Mode" in order to reset the parameters to default values. Then use the "Copy Configuration" feature to program the parameters into the test ECM or manually program the parameters to the correct values.