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Scanner Function
Scanner Operation
Figure 4-27 Sample manual scale selection
The dialog box closes and the parameter scale is now at the set values.
Using Zoom
The zoom options on the Data Buffer toolbar allow you to change the magnification level of the
sweep when viewing data graphs. Use the
Zoom In (+)
icon to increase magnification, and the
Zoom Out (–)
icon to decrease magnification.
Functional Tests
The
Functional Tests
selection is used to access vehicle-specific subsystem and guided
component tests. Available tests vary by manufacturer, year, and model, and only the available
tests display in the menu.
There are four general types of functional test operations:
•
Information Tests
—are read-only tests, like selecting “VIN” from a Functional Tests menu to
display the VIN of the identified vehicle.
•
Toggle Tests
—switch a component, such as a solenoid, relay, or switch, between two
operating states.
•
Variable Control Tests
—command a certain value for a system or component, such as
varying the spark timing in 1° increments or the EGR valve duty cycle in 10% increments.
•
Reset Tests
—reset the adaptive, or learned, values that are stored in the electronic control
module.
Selecting
Functional Tests
opens a menu of test options that varies by make and model.
Selecting a menu option either activates the test or opens a submenu of additional choices. Follow
all screen instructions while performing tests. How and what information is presented on the
screen varies according to the type of test being performed.
IMPORTANT:
Do not enter any functional tests while driving on a road test. During some functional tests, the
ECM makes changes to ignition timing, fuel delivery, and other engine functions, which may affect
engine operation and vehicle control.
