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Cruise control fix.....on going

Old 07-04-2016, 08:18 PM
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No Lag
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Default Cruise control fix.....on going

Well I tried to clean the actuator and I have tried to clean up broken solder joints and still nothing. No nothing! I think I'll order some capacitors for the control unit next. Ideas?

Picture is before the cleaning.
Old 07-04-2016, 08:46 PM
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KVDR
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Subscribed.

I feel like the cruise control is the absolute very last thing I will ever fix on my car.

At that point I will have achieved perfection and the car will magically ascend to the heavens.
Old 07-04-2016, 09:59 PM
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I would have thought there were some common fixes!
Old 07-04-2016, 10:01 PM
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I think there's lots of info out there -

It's be the last thing I fix because there's always something else that needs attention.
Old 07-05-2016, 12:19 PM
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I just cleaned mine up real nice and put some new lithium grease in there and she started working....but only intermittently. Hopefully you'll have better luck.
Old 07-05-2016, 02:37 PM
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jhowell371
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Mine works too well. All it wants to do is accelerate, to what speed I don't know but at 80 it's still going up. It will disengage with a pull of the stalk but pulling down doesn't seem to want cancel the previous setting. I'm thinking I need to clean the contacts in the switch. Hopefully I can get contact cleaner in there without pulling the steering wheel. Pulling the airbag always makes me a little nervous.
Old 07-05-2016, 02:54 PM
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pdxfj
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Jhowell..

Mine does the same. I've cleaned the servo motor and checked the module under the dash. No change. My control switches are also new, so I don't think cleaning the contacts will make any difference. The CC stalk is only a momentary switch and as long as the stalk returns to center, it is not sticking.

I've done quite a bit of reading and it seems you need to change two caps on the module board since electrolytic caps dry out after so many years.

Figured I would wait until after summer to take the module out again, strip the coating on the board, re-solder the board and replace the caps.
Old 07-05-2016, 03:08 PM
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The fix continued today. New capacitors......and no change. Completely not responsive! What next? Stalk switch?



Getting ready to go with cup of tea.




New caps are much smaller
Old 07-05-2016, 09:58 PM
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plumbum
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Mine had bad cracks in the solder causing it not to work...in a rush I re soldered the board but then when I set the cruise it only accelerated...doh!

Picked up a used unit from wailtail and it works perfect!
Old 07-07-2016, 04:32 PM
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951Tom
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If you get a used computer, look for one off a 968 with a later date code. I think they improved as time went on.
Old 07-07-2016, 05:16 PM
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Originally Posted by 951Tom
If you get a used computer, look for one off a 968 with a later date code. I think they improved as time went on.
Good tip. Fully compatible I assume.
Old 07-07-2016, 10:29 PM
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plumbum
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only the early 944 moduals are different from what I was told
Old 07-08-2016, 11:54 AM
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951Tom
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NoLag, yes same part # according to PET for both the late 944 & 968 computer & actuator motor.
Old 07-08-2016, 01:12 PM
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SloMo228
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My CC actually worked properly but I removed it in the name of adding lightness. I never used it much anyway, it was kind of annoying to me without a "coast/decel" function.
Old 07-08-2016, 11:27 PM
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Giantviper
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Originally Posted by pdxfj
Jhowell..

Mine does the same. I've cleaned the servo motor and checked the module under the dash. No change. My control switches are also new, so I don't think cleaning the contacts will make any difference. The CC stalk is only a momentary switch and as long as the stalk returns to center, it is not sticking.

I've done quite a bit of reading and it seems you need to change two caps on the module board since electrolytic caps dry out after so many years.

Figured I would wait until after summer to take the module out again, strip the coating on the board, re-solder the board and replace the caps.
Mine does the same as well.it continuously accelerates. I thought it was the ghost of Mr. Porsche saying drive my car like it was designed 😉. Do you know where I can get the caps or what the part number at an electronics store would be? Also where on the board are these caps you speak of?

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