9.3 - AC Computer ( ,  )

See warning at beginning of section 9.1 page *.

These are often replaced erroneously. The standard of assembly of the Delanaire unit is very high (in stark contrast to the blower assembly electronics!). The board is even conformally coated, which is an expensive process meant to enhance reliability in difficult environments. As the unit sits in a nice plastic enclosure, in an air-conditioned environment, with little electrical stress, this should be one of the most reliable assemblies on the whole car! Apart from abuse by the PO, replacement of the ACC should definitely be an option of last resort!

As an example, very erratic operation of the A/C, sometimes OK, sometimes wrong settings (hot on hot days and vice versa!), sometimes no action at all may be blamed on the computer - but in fact can be due to moisture coming out of the evaporator, running down the RHS of the transmission tunnel onto the single in-line fuse holder that carries the supply current to the AC computer. The contacts corrode slightly, breaking the supply current, and giving intermittent operation of the ACC. A new inline fuse, plus fixing the drainage, will solve this problem.