[V8] Who Works on ECUs?

[dsaad AT icehouse DOT net]

This is interesting - did the new ISV cure your problem before?
If so maybe it somehow took out the driver. Not likely since these  
things are usually over current protected but you never know.



If you don't have the ISV schematic,
the Black/Red wire should be 12v all the time
the Brown/Red wire goes to pin 4 of the ECU. The closer to ground  
this voltage is, the more "on" the ISV is.
If the Brown/Red wire is at 12v and never goes toward ground then the  
driver is toast, or if it is stuck at ground (or very near it) the  
driver is toast. You may need an oscilloscope to really see what is  
going on but a good digital volt meter will probably do the trick.

Dave


On Jan 18, 2006, at 9:59 PM, Carol, Dave, and Zach Weiss wrote:

> To all who responded (Ingo, Ed, Steve, Dave), thank you.
>
>
>
> Bad back has forced me to take it into a reputable shop (not sure  
> which
> hurts more), so I don't have all answers at my fingertips.  They  
> did look
> for vacuum leaks and checked the cruise control.  Accelerator cable  
> was
> binding slightly and has been replaced.  The ISV is new; old one was
> throwing a code (short to ground) and had about 70k miles on it, and
> cleaning had no effect.  Speed sensor is also new.
>
>
>
> I'll ask whether idle changed when unplugging ISV but assume that  
> it did.
> It really sounds like when the speed sensor input gets screwed up,  
> the ECU
> clamps the idle output.
>
>
>
> So does anyone know who works on these (my soldering skills are  
> mediocre,
> and the shop has the car) or what is a reasonable price from a  
> yard?  Sounds
> like a computer from an automatic should be ok, and I should be  
> able to swap
> the chips.
>
>
>
> Dave
>
>
>
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