The method is a component that controls or protects several EZ500 working parts. When one of the work pieces fails, it will affect the control, resulting in other work pieces can not work properly. When use xtool EZ500 Full System. Here is : http://www.xtooleshop.com/wholesale/xtool-ez500-full-system-diagnosis-for-gasoline-vehicles.html

When the control is faulty, we do not know which of the work pieces is faulty. Let one of the work pieces do not work, if the control pieces and other work pieces work properly, then the work piece is damaged.

    Example: a Mercedes-Benz 320 sedan sometimes XTOOL EZ500 HD no air conditioning, fan does not work, often burn 21 insurance.

From the insurance note that the insurance control fan speed resistance of the power cord, control the wiper, and provide one of the air conditioning power cord. EZ500 HD:http://www.xtooleshop.com/wholesale/xtool-ez500-hd-heavy-duty-diagnosis-system-with-special-function.html

So remove the fan speed control resistor plug, or burn insurance; unplug the automatic air conditioning computer plug, still burn insurance; then unplug the wiper plug, because the power cord for the main wiper nozzle sensor to provide FireWire, in the pull When the plug was plugged, we foundEZ500 diagnosis could find a loose sign between the harness bracket and the sprinkler.

When the engine cover is closed, the harness is clamped by the engine bracket. After the correct handling, the fault is resolved.

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