VAG401 VW/AUDI/SEAT/SKODA
www.Xtooltech.com
6
1. Preparation for Testing
The VAG401 aids in monitoring electronic and emissions-related faults in
your vehicle and retrieving fault codes related to malfunctions in these
systems. Mechanical problems such as low oil level or damaged hoses,
wiring or electrical connectors can cause poor engine performance and
may also cause a “false” fault code. Fix any known mechanical problems
before performing any test. See your vehicle’s service manual or a
mechanic for more information.
Check the following areas before starting any test:
Check the engine oil, power steering fluid, transmission fluid (if
applicable), engine coolant and other fluids for proper levels. Top off
low fluid levels if needed.
Make sure the air filter is clean and in good condition. Make sure all
air filter ducts are properly connected. Check the air filter ducts for
holes, rips or cracks.
Make sure all engine belts are in good condition. Check for cracked,
torn, brittle, loose or missing belts.
Make sure mechanical linkages to engine sensors (throttle, gearshift
position, transmission, etc.) are secure and properly connected. See
your vehicle’s service manual for locations.
Check all rubber hoses (radiator) and steel hoses (vacuum/fuel) for
leaks, cracks, blockage or other damage. Make sure all hoses are
routed and connected properly.
Make sure all spark plugs are clean and in good condition. Check for
damaged, loose, disconnected or missing spark plug wires.
Make sure the battery terminals are clean and tight. Check for
corrosion or broken connections. Check for proper battery and
charging system voltages.
Check all electrical wiring and harnesses for proper connection. Make
sure wire insulation is in good condition, and there are no bare wires.
Make sure the engine is mechanically sound. If needed, perform a
compression check, engine vacuum check, timing check (if
applicable), etc.
Operation Instructions
