Audi 80 1998 Auto serious heater problem

Hi

I just read another post with pics of the hoses involved

https://www.vwaudiforum.co.uk/forum/s...ad.php?t=91652

This must be a LHD as the brake servo is on the other side on our cars. The hose with the temp sender indicated, and the one alongside it, are the 2 that need to be joined together to bypass the matrix.

Unfortunately, if the matrix is the culprit it is a dash out job. It is located in front of the heater controls inside a box with diverter flaps and the various ducts attached. It is not a technically difficult job, but there are quite a few steps involved, so takes a while, and you need some room to work.
I don't know of a specific How to thread that covers this, but they are about on the net.