replacing climate/heater unit on a '96 se

[the.oak]

hi there.

I am about to replace my heater/climate controls on my trusty 1996 tdi avant (great mpg, not the most thrilling drive:().

Is anyone aware of any problems, things i might need to know when swapping over the two units? or is it just a plain and simple straight swap??

the haynes manual said something about setting the unit to a "reference" ???



Also does anyone know if a climate/heater control unit from a 1997 A3 is the same as that in a A4 ? The front of the unit is exactly the same.
Having not seen the unit i am not sue if it has differing connections on the rear or not????

any help appreciated

thanks J.

[audimad]

Pretty sure as long as numbers match its a straight swap, good luck !!

[rhencullen1989]

Hi, i removed and fixed mine (flashing lcd panel) i also followed the haynes manual and saw the bit about reference position, i just turned the fan down to zero till the temp display goes out, no probs when re-fitted.

[Zenerdiode]

1996 was right on the change between Zexel and Nippondenso (or just 'Denso') compressors. The two compressors require a different controller, as one of the compressors (I can't remember which) has a pulley speed sensor on it. This was used to calculate any belt slippage and report it as a fault. The speed sensor was later dropped.

Again the A3 1997 one may look identical and have identical plug couplers but will have different firmware inside of it.

Setting to the 'reference' as the Haynes says, is using the Basic Setting function of the factory diagnostic tool or Vag Com or similar. You connect to the HVAC controller, initiate Basic Settings on group 01 and wait until all the fields of the display 0 0 0 0. What this does is moves the air direction and temperature flaps to their extremes and stores the end-stops as a benchmark reference.

[the.oak]

hi thanks for your responses.

i did get hold of the 97 A3 unit as mentioned. I have yet had time to compare the two units. Although on the label details of the a3 unit it does say AB / B5 , maybe the B5 bit anything to do with an A4 ??

Zenerdiode , you seem to know what you are on about, would you not recommend swapping the two units over ???

surely the basic functions/actions can't be that different?