Volkswagen-Audi Vehicle Communication Software Manual [888kb ...

Testing
Testing Engine Systems
2. Scroll past the last line and the scan tool attempts to communicate with the next group in the
list and displays the Requesting Data Group screen.
3. After communication has been reestablished, the next group for that vehicle displays.
In this way it is possible to scroll though all the data groups, scrolling in the opposite direction
moves through the groups in reverse order.
Codes & Data
Selecting Codes & Data displays codes and data together.
NOTE:
i The data in the Codes & Data display are preselected from the individual display groups. It is
important to note that except for a few early models (with only one display group 000) the
preselected “codes and data” represents a limited list that may not include all possible display
groups. There may be more display groups available in Expert Mode than in standard mode.
Check Expert Mode for any missing display groups.
Reading Codes & Data or individual display group data (Measuring Value Blocks 08) can be used
for testing as the engine operates normally. The scan tool does not affect the control module when
reading data (08). This is not true for 04-Basic Settings (see page 22).
5.2.4 Functional Tests
The Functional Tests menu gives you the ability to activate components of the engine
management system.
Initiate Actuator Tests
Which actuators can be activated depends on the control module under test and the vehicle itself.
Actuators can include the following:
• Fuel pump relay
• EVAP canister purge valve
• Injector valves (odd and even cylinders)
• Oxygen sensor (O2S) heater relay
IMPORTANT:
The Fuel Pump will run continuously while the Actuator tests are in progress.
The scan tool commands the control module to activate a component, but it does not check
whether the component is actually operating correctly.
In most cases, the effect can be clearly heard: a relay clicks or a pump runs. Be aware, actuators
can be mounted anywhere within the vehicle, (i.e., under the dashboard, under the hood, and
even in the trunk). If no reaction can be heard at all, measure the actuator with an oscilloscope or
a multimeter. This indicates whether the control module is controlling the component properly.
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