Expected someone to catch this. Thought about it later myself but "send" button already pressed... To test cold start valve simply swap electrical plug with warm up regulator (which you already know is electrically OK). A lot easier than running wires to jump start post and block. Apologies. Bill Robertson #5939 >--- In dmcnews@xxxxxxxxxxxxxxx, "content22207" <brobertson@xxxx> wrote: > > Just run 12v into valve from jump start post and ground to the block. > If valve pumps, know you've got a bad thermal time switch (or wiring > to it bad). >