S4 and Greater Fan Control Module
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From: Gone. On the Open Road
I'm interested in one or more of these depending upon the target price.
It is interesting to note that all the folks above chiming-in for a new controller are from warmer climates. I'll consider it anecdotal - if not statistically significant yet - that the controller's lifetime is a function of how much time it spends 'on' doing work. I've never, yet, found a dead one in a car that's lived its life in Yankee Land.
It is interesting to note that all the folks above chiming-in for a new controller are from warmer climates. I'll consider it anecdotal - if not statistically significant yet - that the controller's lifetime is a function of how much time it spends 'on' doing work. I've never, yet, found a dead one in a car that's lived its life in Yankee Land.
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From: Muenster, TX
dr. bob, that is the idea. We want to maintain the original housing given its location. The next step in the process is to do a board layout such that it fits in the current chassis. Currently, we believe we can get away with removing the small heat sinks attached to the fet's. Modern fet's are much more efficient and manufactured using modern materials. Removing the heat sinks will give us a bit of leeway on how we do the actual layout.
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dr. bob, that is the idea. We want to maintain the original housing given its location. The next step in the process is to do a board layout such that it fits in the current chassis. Currently, we believe we can get away with removing the small heat sinks attached to the fet's. Modern fet's are much more efficient and manufactured using modern materials. Removing the heat sinks will give us a bit of leeway on how we do the actual layout.
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We kicked around building an 'enhanced' unit that accepted the same input voltage but allowed you to connect a variable speed fan or fans. Not sure how interesting that is.
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I believe that it's just a matter of time before ALL of these units will need to be replaced. Heat seems to be the problem for these original units.
If I may suggest, John, that the new units be produced independent of the the old units, else, you will always have the problem of "cores". Additionally, are you sourcing the plug as part of the new unit or planning to reuse the old plug. I would up for 2 of these, BTW.
If I may suggest, John, that the new units be produced independent of the the old units, else, you will always have the problem of "cores". Additionally, are you sourcing the plug as part of the new unit or planning to reuse the old plug. I would up for 2 of these, BTW.
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From: Boulder Creek, CA
Nope. The unit will electrically function as before. It just so happens that the newer components are just electrically more efficient, so it will create less heat.
We kicked around building an 'enhanced' unit that accepted the same input voltage but allowed you to connect a variable speed fan or fans. Not sure how interesting that is.
We kicked around building an 'enhanced' unit that accepted the same input voltage but allowed you to connect a variable speed fan or fans. Not sure how interesting that is.
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DaveC: My thinking is that module failures are a telltale that the fan motors are drawing excess current as they age. For those of us in the warmer climates, that means more fan runtime and perhaps accelerated fan wear. I plan to do a little Ammeter testing on my "current" fans before I pull them and replace bearings and such. Then an 'after' set of readings to see if my theory as anywhere close to fact.
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Its coming & drawing from something fused in the CE panel..right?
Its either less heat = more V's to the fans, or less heat = less draw to run the unit from the CE.
Not trying to argue..just trying to understand where a # of watts of heat is no longer being drawn from...that makes THAT subsystem more stable as well.
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From: Austin, TX
Bought my '95 with this part having already failed, now I am replacing it. Not sure anyone bothered to diagnose that it failed or even knew it had failed before I bought the car, but I have a used one on the way and with all my other cars I am certain to see several of these fail, so a cheaper better alternative would be a HUGE benefit to me!
I agree with the thought that these are going to be failing with greater frequency as they age... Just like the injection brains on the S4's...
I agree with the thought that these are going to be failing with greater frequency as they age... Just like the injection brains on the S4's...
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From: Cambridge England
The newer ouput FETs have lesss internal resistance when turned on than the old ones. It is this resistance times the draw current squared that gives the power that needs to be disspated by the box/heatsink.
As Dr Bob says, the fan current is fixed by the fans themselves.
As Dr Bob says, the fan current is fixed by the fans themselves.
Then where is the less heat being account for.
Its coming & drawing from something fused in the CE panel..right?
Its either less heat = more V's to the fans, or less heat = less draw to run the unit from the CE.
Not trying to argue..just trying to understand where a # of watts of heat is no longer being drawn from...that makes THAT subsystem more stable as well.
Its coming & drawing from something fused in the CE panel..right?
Its either less heat = more V's to the fans, or less heat = less draw to run the unit from the CE.
Not trying to argue..just trying to understand where a # of watts of heat is no longer being drawn from...that makes THAT subsystem more stable as well.
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From: Nebraska
That wouid be nice if it did use the original housing. I am also interested. If we are looking at 20 to make it cost effective I wonder if we could find 10 pre-orders and find a vendor to take on the other 10 for future sales.