'91 200TQ: installing aftermarket stereo

[Barton Oleksy]

Since our factory deck has a problem (intermittent cutting out, won't
turn on sometimes), we were going to replace it with a Pioneer cassette
deck (bought used).  Had a fellow try to install it yesterday but ran
into a problem, possibly with the anti-theft system or internal amp (?)
or something, as he couldn't get any sound to come out of any of the
speakers.

I did try a search of the archives but couldn't find anything related to
this, yet I'm sure it would be a well-known problem to overcome when
replacing the factory deck on these cars.

Anyone have a link to a site with details on this, tips, tricks, etc.?

Interestingly enough, he replaced the original deck after two hours of
fiddling around, and it still retained all its settings, including
presets.  Good thing, too, as I don't have the security code for it!

Thanks for any and all help with this...

Bart
'91 200TQ
'86 CGT