[s-cars] heater problem

[Rich Assarabowski]

To add to Fred's comments, run the diagnostics on the climate control
and if they indicate the temperature flap motor, replacement of the
motor is pretty straightforward (pull wipers, wiper motor and linkage
and a plastic cover), all done from the engine compartment.  It's a
common problem, replacement motor is $75 (P/N 443 820 511A).  Might be
just a stuck linkage, check that first.  I suspect it's the pots that go
bad on these, but don't know...  Another fine component from your
friends at Bosch.

-- Rich A.
   92 & 93 S4

>Jerry;
>
>By design, hot coolant always runs through the heater core. The cabin
temperature is controlled by flaps inside the box
>which mix hot and cold air to maintain the temperature set point. If
the flap mechanism, drive motor, or positioning pot
>is screwed up, you may only get cold air. There are two rubber hoses
about 1" in diameter running up through the firewall >from the back of
the engine to the heater box. Feel these hoses to make sure they are hot
- this indicates coolant is
>going to the heater core. Run a diagnostic on the climate control unit
- the Bentley tells you how and what the trouble
>codes mean.
>
>HTH
>
>Fred Munro
>'94 S4