Scan Tool Operating Instructions - AK Automotive Training

Manufacturer Applications
A feature of these systems is that fault codes are transmitted twice, so although the
repeated codes will appear on the screen, the final code listing will only display the
faults once.
During the test, the OmiCheck application will instruct the user to perform actions. For
instance, Turn the steering wheel or Press the throttle. These actions not only allow
the system to test the switches but also indicate to the vehicle to progress through the
test. If these actions are not followed, the test result output indicates that the test was
not performed correctly. The user should make a judgement as to whether this is
correct or that a switch is faulty.
KO EO Test - Key On/Engine Off Self Test
KO EO test runs the complete set of functions:
1. Read present fault codes. This function will take a while but an indication of
progress should occur within one minute. If there is no response, assume
communication problems and check the connection and that the ignition is turned
on as and when instructed.
2. Read KAM fault codes. This operates in the same way as reading present fault
codes as described above.
3. Actuator (circuit) tests. While Actuator test is displayed, pressing the throttle will
cause actuators and relays to be turned on and off in line with the throttle switch.
Listening and feeling the relays enables the user to determine the function of
these circuits.
4. Wiggle test. This routine functions in the same way as the wiggle test listed
below.
KO ER Test - Key On/Engine Running Self Test
KO ER test requires that the engine is at normal operating temperature (above 80°C).
A good indication of this is when the cooling fan switches on for the first time.
The testing is performed in the same manner as the KO EO test with the exception
that there is no Actuator test available. There may be more user operations to perform
so it is recommended that the OmiCheck screen be watched carefully.
Wiggle Test
Wiggle test is used to look for open-circuit wiring faults between sensors and the
engine controller. The controller responds quite slowly to this test so slow movements
of the wiring should be undertaken to generate a wiggle test fault.
Practice the wiggle test by removing and replacing a connector like the throttle
potentiometer and watching the OmiCheck display for the change of state.
Some sensors can only be detected in the KO EO condition while others only in the
KO ER mode.
228