View Poll Results: Does the cruise control on your car work?
Voters: 68. You may not vote on this poll
Naïve idea: is it possible to re-fabricate VDO Cruise Control Amp?
#1
Burning Brakes
Thread Starter
Naïve idea: is it possible to re-fabricate VDO Cruise Control Amp?
Hi everyone,
Perhaps this is a naïve idea, but I wanted to throw it out there after reading this very interesting thread.
I've been through 7 cruise control brains between my two 928s, and only one of them works properly.
I've tried the solder method (twice) and it hasn't worked for me. (My soldering technique was developed in the eighth grade, then in lab electronics in college- where I barely squeaked by with a B-. I suck at it.)
Perhaps this is a question for Alan Moore, PorKen, or another resident electronics luminary:
How difficult would it be to recreate VDO's cruise control brain, if we got, say, 100 or so people to buy in? Could we 'commission' a small, low-cost computer, with wiring to connect to the VDO wiring harness- something that would be bulletproof?
(I would be happy to do all of the legwork. This would not be a money-making venture- it would be a 'public service' for the 928 and 911 community.)
Perhaps this is a naïve idea, but I wanted to throw it out there after reading this very interesting thread.
I've been through 7 cruise control brains between my two 928s, and only one of them works properly.
I've tried the solder method (twice) and it hasn't worked for me. (My soldering technique was developed in the eighth grade, then in lab electronics in college- where I barely squeaked by with a B-. I suck at it.)
Perhaps this is a question for Alan Moore, PorKen, or another resident electronics luminary:
How difficult would it be to recreate VDO's cruise control brain, if we got, say, 100 or so people to buy in? Could we 'commission' a small, low-cost computer, with wiring to connect to the VDO wiring harness- something that would be bulletproof?
(I would be happy to do all of the legwork. This would not be a money-making venture- it would be a 'public service' for the 928 and 911 community.)
#2
Archive Gatekeeper
Rennlist Member
Rennlist Member
#3
Burning Brakes
Thread Starter
Hi Rob,
I haven't- several on the board have reported that this works- but others have reported that bringing the circuit board to a temperature high enough to reflow the solder also damages components at the same time. Given my luck with electrical components I didn't try it.
My '86 and '87 had inoperative CC brains. I bought three used brains for very cheap from a used parts dealer (not 928Intl) and they didn't work. Then, I bought two "refurbished" units. One sits in the '87 and works. The other sits in the '86 and worked for a while- now it is intermittent, at best.
Buying another refurbished CC brain is possible, as is reflowing the solder with a gun or an oven... but isn't there a better way?
I haven't- several on the board have reported that this works- but others have reported that bringing the circuit board to a temperature high enough to reflow the solder also damages components at the same time. Given my luck with electrical components I didn't try it.
My '86 and '87 had inoperative CC brains. I bought three used brains for very cheap from a used parts dealer (not 928Intl) and they didn't work. Then, I bought two "refurbished" units. One sits in the '87 and works. The other sits in the '86 and worked for a while- now it is intermittent, at best.
Buying another refurbished CC brain is possible, as is reflowing the solder with a gun or an oven... but isn't there a better way?
#4
Rennlist Member
If some one could program a Raspberry Pi to take the analog input of the switch and then trip a set of relays that would be great.
Or even use an arduino to make a CC computer. The biggest problem would be the programming because many of us here don't know how to use C++ or other program scripts.
If some one is willing to do this, that would be awesome
Or even use an arduino to make a CC computer. The biggest problem would be the programming because many of us here don't know how to use C++ or other program scripts.
If some one is willing to do this, that would be awesome
#5
Rennlist Member
Scott,
These places do reverse engineering (many do I'm sure) so you might want to send one CC to them for an estimate.
http://www.silvercircuits.com/index.htm
http://www.americancircuits.com/aci/...6/Default.aspx
Cheers!
Carl
These places do reverse engineering (many do I'm sure) so you might want to send one CC to them for an estimate.
http://www.silvercircuits.com/index.htm
http://www.americancircuits.com/aci/...6/Default.aspx
Cheers!
Carl
Trending Topics
#8
Hi Rob,
I haven't- several on the board have reported that this works- but others have reported that bringing the circuit board to a temperature high enough to reflow the solder also damages components at the same time. Given my luck with electrical components I didn't try it.
My '86 and '87 had inoperative CC brains. I bought three used brains for very cheap from a used parts dealer (not 928Intl) and they didn't work. Then, I bought two "refurbished" units. One sits in the '87 and works. The other sits in the '86 and worked for a while- now it is intermittent, at best.
Buying another refurbished CC brain is possible, as is reflowing the solder with a gun or an oven... but isn't there a better way?
I haven't- several on the board have reported that this works- but others have reported that bringing the circuit board to a temperature high enough to reflow the solder also damages components at the same time. Given my luck with electrical components I didn't try it.
My '86 and '87 had inoperative CC brains. I bought three used brains for very cheap from a used parts dealer (not 928Intl) and they didn't work. Then, I bought two "refurbished" units. One sits in the '87 and works. The other sits in the '86 and worked for a while- now it is intermittent, at best.
Buying another refurbished CC brain is possible, as is reflowing the solder with a gun or an oven... but isn't there a better way?
You are correct in the fact that components can be damaged in an ordinary oven. I would suggest not to "reinvent the wheel" but to determine what the failure mode is in the original board and correct this with a design change.
Just my .02
#9
Racer
Join Date: Jan 2014
Location: Winnipeg, Manitoba Canada
Posts: 485
Likes: 0
Received 1 Like
on
1 Post
There are other alternatives to solder, that may work.
Electrically conductive glue and epoxy's are used for many applications, many more severe than a circuit board. They have been used for low volume circuit boards but are too expensive when the volume goes up. Ideal if you know which pins are loose or where there is a break in the board.
Something like this, and I have no affiliation
http://www.circuitspecialists.com/8331-14g.html
Lance
Electrically conductive glue and epoxy's are used for many applications, many more severe than a circuit board. They have been used for low volume circuit boards but are too expensive when the volume goes up. Ideal if you know which pins are loose or where there is a break in the board.
Something like this, and I have no affiliation
http://www.circuitspecialists.com/8331-14g.html
Lance
#10
Burning Brakes
Thread Starter
Hi Lance,
The trouble with reflowing the solder is that you never know which pin is loose. Or, at least, I didn't by visual inspection. That's why you have to go through and spend the two hours to reflow every connection- and not make a mistake.
The trouble with reflowing the solder is that you never know which pin is loose. Or, at least, I didn't by visual inspection. That's why you have to go through and spend the two hours to reflow every connection- and not make a mistake.
#11
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
I just don't see them as unreliable enough to warrant this. By your own account you are buying risky ones and had poor ones... get a good one and be done with it?
If they were really billed as refurbished - send them back as DOA.
Alan
If they were really billed as refurbished - send them back as DOA.
Alan
#13
Former Vendor
Certainly a percentage of the brains are going to have "soldering issues".
However, there's going to be a percentage that have component issues.
It's not realistic to think that any one fix is going to fix all the units.
As far as remaking pieces.....Anything can be re-made.
Getting something made for this tiny, tiny market is the problem, so someone generally has to undertake something like this as a "hobby".
However, there's going to be a percentage that have component issues.
It's not realistic to think that any one fix is going to fix all the units.
As far as remaking pieces.....Anything can be re-made.
Getting something made for this tiny, tiny market is the problem, so someone generally has to undertake something like this as a "hobby".
#14
Burning Brakes
Thread Starter
However, I must add that almost all of the two dozen or so 928 owners I've physically met do not have a working cruise control. It seems to me that the CC units are indeed quite unreliable, compared to the other systems in the car that seem to work for most people: EZF, LH, etc.
(That might be perception of course: one can "live with" a faulty cruise control, not so much with a bad ECU.)
Scott,
These places do reverse engineering (many do I'm sure) so you might want to send one CC to them for an estimate.
http://www.silvercircuits.com/index.htm
http://www.americancircuits.com/aci/...6/Default.aspx
Cheers!
Carl
These places do reverse engineering (many do I'm sure) so you might want to send one CC to them for an estimate.
http://www.silvercircuits.com/index.htm
http://www.americancircuits.com/aci/...6/Default.aspx
Cheers!
Carl
#15
Burning Brakes
Thread Starter
This is what is so frustrating to me. With one of my CC "brains" I reflowed the solder, and even got "fancy"- by testing the transistors with a "diode tester" (read: multimeter) to see if any of the transistors were bad. It took hours, the transistors seemed to be "good," and after all of that work, no change.