need help with 98 a3 1.8t non bose with aftermarket HU


Registered User
Jan 10, 2013
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Hi I just recently bought a 98 1.8t that came with a non bose stereo and rear amp.
After installing a new HU I noticed the rear speakers and sub weren't working and the HUs memory resets every time i turn the car off.
After reading a few threads I think I've worked out i need to switch the red and the yellow wires over for the memory to work?
I've read about getting a pc9-404 adapter or something to get the rear speakers and sub working but also heard that it sounds pretty poor because its only a 20w amp. Few people have said to wire the rear speakers directly into the HU but i was wondering is it the brown plug i wire them into or the pre outs?
Also is there any chance i could then get the standard amp working with just the sub without this pc9 adapter, like rewire it into the preouts or something? and could i bridge the channels to the sub for more juice? Or could I use my own aftermarket amp to power the standard sub but just turn everything down?
I also have my own sub i could install but if i can get the standard one sounding half decent then i could deal with it for the stealth. I've read about andymac's stealth subs which look awesome but I'm a student and cant afford it at the moment
I'm pretty new to all this kind of stuff but want to learn and look after my car :)