How to make a 12V DC logic probe

[jtw401]

Im wondering if i can buy OR DIY a logic probe kit for automotive purposes...i already own an OTC probe that flashes green-ground, red-power, amber-signal as well as pulse....but id rather make one
I have already made a LOADpro test lead set, and Power Probe (though id love to know how the hell one makes a Sealey PP100, that thing is the truth!), and im pleased with results...started out as hobby, and after a few prototypes, i prefer my final designs of each, and figure i can do the same with a quality logic probe
I also plan to do a normally closed momentary switch/25ohm resistor and detachable test light leads-DMM bananas to let it act as a loadpro on B+ side...anyone familiar with a circuit diagram to do this?
Ive seen Elenco (made a couple decade boxes from em) has a logic probe kit, on the 5v style for circuitboard work...i want one for 5 and 12v systems, with hi-lo
i know transistors and diodes definitely gonna be involved, and i kindly ask if anyone has design suggestions, they provide part #s as well

 

[jtw401]

also, please dont be like "just use the one you got, some of us have to work and dont have time to make stuf...blahblah!!"
This is primarily hobby why im questioning the idea...i think a good discussion on homemade test lights is ALWAYS prevalent for those who make their only income off solving diagnostic/electrical problems, such as myself.
Also, Craftsman makes really awful tools now...unrelated, i know...but dear god...

 

[scarney1988]

NVM. The above thread was not yet posted.

What features would you like in an adequate design?

Good luck

 

[signcrafter]

I can't help you any but love making my own tools also. I'll be watching this thread. Any more details or pictures of the testers you have made?

 

[cousin eddie]

i dont know what the hell youre talking about, but since you got me thinking about it, ive been looking for a testlight that doesnt pierce the wire, that can sensce voltage through the insulation. im talking about 12 volt systems here. those of you who also live in the snow belt know what happens to wires that were poked with a probe when the salt hits it.