Stupid question about l.e.d. probes.
 

Hi, hope this is the right place. Seemed like a good idea; anyhow, I replaced my ignition coil yesterday afternoon when the tow-truck dropped us off, had to (really!😉) Buy a l.e.d.

probe for the troubleshooting, it was relatively cheap, but now that it's served this purpose, what now? But mostly, seriously, what else can I use it for? Will it detect hall effect devices? Etc? Like I said, stupid question, just something was pondering. Love the sight, actually didn't have to ask questions this time, had plenty of info.

What kind of led probe? For timing adjustments? Can you find a link somewhere online?

It's a dormant conduct-tite. Looks like part# 86602 from O'Reillys in Oklahoma. Needed it to check for control and ignition signal when troubleshooting coil/ICM.

Package says " Computer Safe automotive Logic Probe.

Looks to me that it will only sense logic outputs, so +5V for 'true' and 0-1V for 'false' and it takes 12V to run. Not really that useful for anything other than what it is intended for. If you do logic testing often, it would be nice to have, but if it's something you don't do ever, then maybe not. If you were to try to use it on any other type of automotive circuit, you may damage it as they mostly use the 12V on or off. I doubt the sensing circuitry is designed to run on 12V unless it says specifically that it can. If it can operate on 12V, then you could use it to check to see if various points on the vehicle are receiving +12V or not, which could be more convenient than a DMM, or if you don't have one of those it could help with that kind of thing.

It's an automotive tool, Thogert, not a computer "logic probe".

It's "computer safe" compared to the test lights it supersedes. Back in my dad's day, every mechanic who did electrical work had a "test light" which was basically a light bulb socket with one short wire soldered to a scratch awl or ice pick, and a long wire with an alligator clip. If you were checking for power, you'd ground the alligator clip and poke around and watch the light bulb. If you were looking for a ground, you'd connect the alligator clip to the battery and poke around. That tool works on a 1950's Chevy, but even with a low wattage bulb (7W), it draws a lot of current (about half an Amp) from the circuit you're testing. That current is enough to damage an electronic ignition module or an ECM if you poke around with that kind of light.

The Dorman tool, and "LED Probes" like that one, get power from the two alligator clips. The probe has a very high input impedance, like a volt meter. It gives you one light (or one color) when connected to positive voltage, and another light (or a different color) when connected to ground. Some of these probes also have a small speaker and generate different tones for voltage and ground.

The Dorman tool, and similar "LED Probes," are useful for checking for voltage or ground, checking the operation of relays and other things where you might use a volt meter, but are only really looking for battery voltage or ground. It's for things like checking fuel pump wiring and relay operation, checking electric fan wiring and relay operation, air conditioner compressor clutch wiring, and other things like that where you're tracing wires and checking for voltage or ground at multiple locations.

Ahh, well I stand corrected. My assumption was that since it said 'logic probe' it would read logic levels, it should say it's a test light if that is all it does. Computer safe also muddys the waters for me. Oh well, assumptions based off my own experience bite me in the butt sometimes. :)