[redhorse]

Has anyone ever repaired a late 944 or 968 heat and air control unit? By that I mean, you either replaced some discreet components or one of the pushbutton switches. I am looking for feedback on what is possible and hopefully the schematic of the switch itself.

Seems these cars are notorious for switch buttons that lose the ability to stay in the "on" position (looks to be the fault of a small piece of white plastic that wears). I have searched the web and only found one article that looked like someone was trying to repair the switch, but it was in Japanese or similar language I couldn't read.

Also, on reading some parts sources for AC replacement switches, I see disclaimers that the part is for control units that have removable switches. What does this mean? Did some control units come from the factory with plug in sockets for the ac switch? All of the units I have seen have the switches (ac, fan control, temp, recirc/defrost) soldered to a base circuit board.

After disassembling one non-functioning ac switch while it was still soldered on, I am of the under-informed opinion that the switch cannot be repaired, only replaced. Odd to think that a switch that is so easy to wear out, and has hard mounted lights in it (that burn out at some point) would be so difficult and expensive to replace.

Does anyone have any experience with any of this that they can share? I know there is at least one entity out there that repairs these control units, but they are priced high enough that I would rather purchase a discounted new unit or better still, install a substitute. Has anyone found a schematic for the circuits boards in the control unit? I have an electronics background, and would like to reverse engineer this unit and design an interface to a replacement that fits the same opening. Give the parts on the control unit, and the lack of enduring quality for the main components, a new 'non-Porsche' system like it should not cost much over a $100.

Thanks!

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[PorscheDude]

Easiest thing to just replace the controler.
Check eBay, there's usually 5 or 6 for sale at any givin time.
One from a 85.5 and later 944 will work.

As it gets colder outside the prices tend to come down 10% to 20%.
Do not pay more than $100.

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[Ryan]

It is a simple change-out as everything wiring wise has plugs. Just remove the trim and a few screws and out it comes. I replaced the unit in my 944.

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[redhorse]

<!--quoteo(post=80364:date=Sep 20 2009, 07:11 PM:name=PorscheDude)-->QUOTE (PorscheDude @ Sep 20 2009, 07:11 PM) <{POST_SNAPBACK}><!--quotec-->Easiest thing to just replace the controler.
Check eBay, there's usually 5 or 6 for sale at any givin time.
One from a 85.5 and later 944 will work.

As it gets colder outside the prices tend to come down 10% to 20%.
Do not pay more than $100.<!--QuoteEnd--><!--QuoteEEnd-->

I bought two off eBay, and both have defective switches. The sellers lie about the condition of the units to sell their non-working junk. I won't buy a third.

Therefore, I prefer to repair a controller with new switches, or better yet -- find a substitute. I am sure there is a schematic out there somewhere, or maybe someone knows where one can be obtained.

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[968 GUY]

I replaced one in my 968 because the clear plastic piece was trashed. All the switches were working, the controller was loose because of the cracked and broken screw holes. Somewhere I have seen new clear pieces, I just cannot remember where, seems like it was a european part that some parts place had gotten hold of a bunch. Maybe someone else has seen them...? I am looking thru all my favorites and searching my memory,maybe I will come up with it. But, if you want the controller, let me know.

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