[Vwdiesel] Tach signal box

[Dave Heart]

Since this is a real odd problem I might just build a new black box. I 
really like this approach to getting a regular tach signal which allows 
cruise control as well.  I did draw my own circuit board using etchant to 
make the board and used surplus parts. Seems odd possibility of a 
malfunction due to sensor reflection becoming poor off the metal tape after 
10 minutes of use but fine before that. I did paint area between sections 
flat black. Cannot figure why everything ALWAYS works fine for at least 
10-15 minutes from engine cold start up. As you pointed out since cruise 
also malfunctions at same time probably the used jetta tach is likely not 
the problem... I moved the black box to inside cabin and only mounted sensor 
in engine compartment thinking maybe heat bothering some component Same 
trouble...Oh well....




>Might want to inspect the circuit board for any loose parts, perhaps a 
>solder joint has
>cracked or a part has overheated.  I've had my circuit box mounted on the 
>fender next to
>the timing belt cover for about 7 years now, never had an issue with it, 
>even on long
>drives in the heat of summer/desert.  Might also check the spacing to the 
>reflective
>strips, they may be too close or too far away.  Might also consider 
>painting the
>in-between parts of the sprocket flat black to not reflect light.
>
>--
>
>    Roger
>_______________________________________________
>Vwdiesel mailing list
>Vwdiesel at vwfans.com
>http://www.audifans.com/mailman/listinfo/vwdiesel

_________________________________________________________________
Don’t miss your chance to WIN $10,000 and other great prizes from Microsoft 
Office Live http://clk.atdmt.com/MRT/go/aub0540003042mrt/direct/01/