2004 Kompressor charging
 

A friend of mine recently acquired a 2004 Kompressor & doesn't have much cash and asked to borrow some torx sockets as the alternator is not charging. Diagnosis was done with a machine at the McParts store.

I can give him some tools & have the alternator bench tested. Is there an external voltage regulator that goes bad? If so, where is it located? If not, how is charging controlled in that car?

The alternator is controlled by the engine control module. The blue wire is not the field but a serial communication link with the module. There are not any easy tests other than alt output. Almost always the alt is the culprit. Beware of cheapo parts store replacements, rarely are they up to snuff.