An excellent tool! I built one a couple years ago "just in case". 

This past weekend I had a no-start problem. By using this tool, and following the diagnostic procedure in the Samba thread, I ultimately determined that my problem was a frayed wire at the alternator which feeds the ECU relay. I had enough power to activate the relay but not enough to start the engine. After tracing the wiring I found the frayed wire which had just a couple strands conducting. I replaced the connector and all is well.

Mark K
1986 GL/2WD/4SPD "Abe"

On May 1, 2013, at 10:41 AM, Steven Johnson wrote:

> You need to cobble together on of these bypass setups to help you diagnose
> the problem:
> 
>                 http://www.thesamba.com/vw/forum/viewtopic.php?t=349429
> 
> Very useful to help eliminate what's going on and rule in/out the fuel pump.
> 
> Steven
> 91 Westy