How to Self-Test the RCM and Main ECU Cable

With the Diagnostic Loop Back Test, you can run a self-test for the Rate Control Module ECU (electronic control unit) and for the main ECU cable. You can choose to test the ECU by itself, or you can test both the ECU and the cable. Please note that the 47-pin test requires the diagnostic loop back cable (115-7347-006). If you do not have the loop back cable, you can run the ECU test and then manually check continuity on the ECU cable.

To get to the diagnostic tests for RCM, tap the Diagnostics button. Then tap the Tests tab. Turn off the Master Switch to access the test drop-down list. Select the test from the list, and then tap the Begin button.

The RCM will reboot into its diagnostic loop back mode. Now read through the on-screen instructions for the test. Once you disconnect the product cable and turn off the Master Switch, the Start button will become available. Also remove the center connector from the RCM if you have one connected.

Now you can select between the ECU and 47-pin tests. Enable the Continuous Test option if you would like the test to run repeatedly. Otherwise, it will only run the test one time, but you will have the option to restart the test as soon as it finishes.

Tap the Start button when ready.

The RCM will perform several quick tests in a row.

• If a test fails for the ECU, the ECU will need to be repaired or replaced.
• If a test fails for the 47-pin, look for and troubleshoot any damage to the pins, connectors, and wiring to determine the failure.
• If all tests pass, reconnect everything as it was before starting the Diagnostic Loop Back Test.

To exit the test, tap the Accept button and then tap the Exit button. The RCM will then reboot back into its normal operating mode.