Even better than a meter

[Concord]

If you've ever tried to diagnose a 12 volt problem, you'll find this the handiest thing! The logic probe from harbor freight. (it's only shortcoming is too short of a wire.. I added 20 feet to mine.)
Connect it to the battery... Then anything you touch with the probe lights up a green light if you touch ground, red if you touch hot. Ten bucks.
Let me know if you've got one and if you agree.

[SteveB]

That's neat. I have a tiny one that was supplied with a remote start kit a very long time ago. Yours is way better.

[Busskipper]

Originally Posted by Concord

If you've ever tried to diagnose a 12 volt problem, you'll find this the handiest thing! The logic probe from harbor freight. (it's only shortcoming is too short of a wire.. I added 20 feet to mine.)
Connect it to the battery... Then anything you touch with the probe lights up a green light if you touch ground, red if you touch hot. Ten bucks.
Let me know if you've got one and if you agree. Attachment 284601

Most just have a single connector for the Ground then the Probe will see if the Circuit is good.

Baffled by the second connector.

Use mine all the time to just see if I have 12 Volts at the Location.

[Vongreg]

What he said

[Wild Card]

Originally Posted by Busskipper

Most just have a single connector for the Ground then the Probe will see if the Circuit is good.

Baffled by the second connector.

Use mine all the time to just see if I have 12 Volts at the Location.

It connects to both ground and positive...lights up green for ground and red for positive. VS a standard 1 wire job that only lights up when you complete the circuit from hot to ground.

[cavie]

Originally Posted by Busskipper

Most just have a single connector for the Ground then the Probe will see if the Circuit is good.

Baffled by the second connector.

Use mine all the time to just see if I have 12 Volts at the Location.

The second connector is needed because they both are conned to the battery. That's why he needed to add the wire extension. The tester lights up 2 different colored lights. New gimmick. I prefer my 50 year old one wire tester like yours. Much easier to use and store.

[Busskipper]

Originally Posted by Wild Card

It connects to both ground and positive...lights up green for ground and red for positive. VS a standard 1 wire job that only lights up when you complete the circuit from hot to ground.

- -

KISS

[R.Wold]

I like it because you get a light if you find a good ground. I can see that coming in handy. And since it tests hot in the same device, why not.

It’s definitely different than a traditional “trouble light” as I’ve always called them and I can see the usefulness for both. As well as an audible continuity testers and all the rest.

Only down side is that it has to run to a good source of hot and ground, so usually connected to the battery and hence the need for the extra 20’ of wire. But you could probably usually find a good hot and ground closer to your work.

[Glennabbott1]

If it requires penetrating the insulation, I'm out. Holes in insulation allow moisture entry and the resultant corrosion.

[Gary RVRoamer]

If it requires penetrating the insulation, I'm out.

It doesn't require any more (or less) holes in the insulation than a meter with probes. The tester has to be able to touch the wire itself, so you probe at connections and other exposed points. Poking thru insulation to reach the bare wire is a last resort (but once in awhile the only way to get 'er done).

[InfinityJim]

It’s a copy of the power probe that's been out for 20 years. I use one all the time, almost daily. The power probe is better IMO because you can do what this one does (identify either positive or negative) but you can also feed the circuit with power or ground. It also has a built in circuit breaker so if you feed power to a ground it trips the breaker. I’m not putting this down, I really like a lot of harbor freight products and spend lots with them every year!

[Dutch Star Don]

OMG....some of the responses don't make sense and are just silly!

I have used a 12 volt probe light for years. Depending on what you're looking for, a ground or hot lead, you had to connect the probe lead to something opposite of what you're looking for. With this tool, connect once to the battery and look for both hot and ground without disconnecting. How can you argue that it's not a good product?

I also use an extension on the probe light because motor homes are so much longer/bigger than cars and you often need more length.

[Xmcdog]

Had several over the years. Seem to grow legs. Great for low voltage. Still like my Fluke though.
Piercing the insulation encourages problems for the future. I've rewired several systems because of this. So unnecessary.

[Concord]

A thinking man! Yes, some of the responses are surprising. I don't always follow it, but sometimes I actually (assume that I don't know EVERYTHING ) and allow myself to learn something new.

One of the most useful places to use this is trailer wiring.. One neat trick is to place the probe on the down (load) side of a switch. If all is well, switch off, and you will see green (the presence of the ground flowing through the filament back to the switch.. Switch on, you will see red.

Originally Posted by Dutch Star Don

OMG....some of the responses don't make sense and are just silly!

I have used a 12 volt probe light for years. Depending on what you're looking for, a ground or hot lead, you had to connect the probe lead to something opposite of what you're looking for. With this tool, connect once to the battery and look for both hot and ground without disconnecting. How can you argue that it's not a good product?

I also use an extension on the probe light because motor homes are so much longer/bigger than cars and you often need more length.