The way some rigs have things separted from each other is can be hard to hear solenoids clicking in or out and without long leads on your DMM its hard to read the meter. What I did is I have a piezo(sp) speaker and hooked some alligator clips to the leads and hook it up to the circuit I am testing. It is not a loud speaker but I can hear it from inside to out and from front to rear.
An LED light or incandescent light can be used with really long leads but I found the sound method was better because I don't have to have it next to me.
