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MODIS Ultra Training Module Six
Applies To: MODIS Ultra™
Functional Tests: Scanner Functional Tests, Scanner Output Controls, Actuator Tests, Custom Data List
Welcome to Snap-on® Training Solutions®. This module is designed to help you get the most out of your MODIS Ultra™ diagnostic tool and covers the use of scanner functional tests.
Functional Tests are a great way to isolate the cause of a problem among the controller, a component, wiring or other issues. Functional tests let you override the vehicle controller to take control of the system and determine if the vehicle responds properly or not. Functional tests are a powerful companion to troubleshooter, which often refers you to perform a functional test to verify a suspected issue. As an example, we will use the injector balance test. Let's begin by reviewing the description of this test. From the main scanner menu, select Troubleshooter, Engine, and Tests and Procedures. Select Functional Test Descriptions to see a list of all available functional tests. Select Injector Balance to see a description of what the test will do for us.
Troubleshooter tells us how to perform and interpret the test. Now that we know what to expect, select the back button to return to the main menu to perform the test. From the main menu, select Functional Tests. Select the Injector Balance test. The next screens give us step-by-step test instructions. Select continue. Select each injector one at a time to disable it and compare the RPM drop between injectors. If you are using a fuel pressure gauge in conjunction with the test, compare pressure drop between cylinders. Select an injector once to deactivate and again to activate. This is known as a toggle test.
Other useful types of functional tests, are actuator tests which check operation of devices like solenoid valves, motors and relays and output controls which monitor live output data from the vehicle while you activate vehicle components. A good example of a powerful output control is the AC Relay test. Select the test and the AC relay control shows at the top of the screen and the live data parameter view opens. By using the functional test and selecting on you are overriding the controller. If you command the relay to turn on and it does not activate, you've just eliminated the controller from the possible causes. This pinpoints the likely problem to be the relay or wiring. In order to choose relevant data parameters to monitor, use the back button to open the data menu.
Custom Data List
Select the data group Accessory Electrical Theft Data. Let's view the data parameters relevant to the AC Relay Test. First, use the Select All icon to de-select all parameters. Select just the parameters you want for your diagnosis. To perform the AC Relay test, we will select AC related data. This will speed the data refresh rate to help you catch short intermittent glitches. Here's your custom data list. Now you can observe the vehicle data response when you command the AC relay on and off.
Snap-on is dedicated to helping you get the most out of your diagnostic tool and keep your customers happy. Be sure to watch the next module in this Training Solutions series.
Last Updated: October 31, 2019