12v circuit tester

[SuzukiGS750EZ]

I used test lights when I first started repairing cars but haven't really used one since, I mostly use my PP3. Looking to buy my brother one who isn't fully electrically smart. I taught him how to use a test light...

Who makes a good light with solid wire and a good clamp? Maybe a voltage readout?

 

[richfinn]

I like this incandescent one from OTC

https://www.amazon.co.uk/dp/B003YNHVQQ/?tag=atomicindustr-21

Not a fan of LED/Digital style because I like to load the circuit or use it for bypass tests (and I own a bunch of multimeters if I need to actually read voltage)

 

[Showkey]

Agree ^^^^^^^^^^^

Also not a fan of power probes..........one misplaced 12 volt probe or direct ground on an unprotected ECM or module circuit and that device is junk. Skilled techs with power probe still make mistake like one cavity or pin to the left or right is disaster. In unskilled hands or novice with the best intensions the results are the same.

 

[vssjim]

i use plain old GearWrench/KD or S&G Tool Aid lights work good and are fairly cheap. Use Standard bulbs also.

 

[plinker]

I like this test light, it is a full size unit though, not a mini.
https://www.tooltopia.com/OTC-Tools-OTC3634

I have a Snap-on test light that has a voltage read out at home, at work (and in general) a meter is more practical for voltage checks IMO.
I also use a Power probe 3 regularly.

 

[joshmodelskidoo]

I have a regular hf and computer safe one also from hf. I have not used the computer safe one yet

 

[2ndGearRubber]

To reliably check a circuit, you need to load it and voltage drop it.

My main test light for "computer" circuits is the otc 3633 mini test light. 1/4 amp draw. That's not going to hurt anything. You can stick that anywhere and not worry about it.

For circuits that actually move current like a fuel pump or blower motor, you need more load. A headlight bulb is 4.5 Amps approx, 3357 tail lamp bulb around 2. Get a pigtail and a bulb, and solder on stacking banana Jack's. Use your meter or scope to voltage drop it. With the stacking leads you can add what ever length leads you need and use backprobes or breakout leads.

 

[2ndGearRubber]

In the most basic situations, voltage drop can be skipped. Jump your 2amp bulb into the washer pump connector, if it lights, its fine, itll run a washer pump fine.

 

[theoldwizard1]

The clamp with almost ALL test lights leave MUCH to be desired !

Buy a small locking pliers and replace the clamp with that !!

 

[theoldwizard1]

In the most basic situations, voltage drop can be skipped. Jump your 2amp bulb into the washer pump connector, if it lights, its fine, itll run a washer pump fine.

Concur, but where do you find a 2A test light ? Most only draw about 250mA (0.25A).

 

[theoldwizard1]

I like this test light, it is a full size unit though, not a mini.
https://www.tooltopia.com/OTC-Tools-OTC3634

I have a Snap-on test light that has a voltage read out at home, at work (and in general) a meter is more practical for voltage checks IMO.

Sure a meter is better for VOLTAGE checks, but a test light will show that the circuit can carry a certain amount of CURRENT. It is very possible to have voltage, but insufficient current in a circuit.

Additionally, an incandescent test light can be used to LIMIT current to device when placed inline.

 

[californiamilleghia]

I would like a simple light with a buzzer so I can put hear when I have power at the tailight etc when I am under the dash......

Also a "tail light bulb " without the bulb but with a power and ground wire ,

maybe you can buy them but I never found them.....

 

[2ndGearRubber]

Concur, but where do you find a 2A test light ? Most only draw about 250mA (0.25A).

3357 tail light bulb. Buy a bulb and pigtail online, or harvest one from a junk taillight assembly. Add stacking banana jacks, or you can depin the connector and use the male space terminals.

I like sealed beam headlamps for even bigger loads, about 5 amps. A normal 9007 or whatever is about 4.5.

 

[2ndGearRubber]

I would like a simple light with a buzzer so I can put hear when I have power at the tailight etc when I am under the dash......

Also a "tail light bulb " without the bulb but with a power and ground wire ,

maybe you can buy them but I never found them.....

Get extendable test leads, various places sell them in 10, 15, and 20 foot sections. Make your connection. And have the test lamp in place where you can see it.

Or use a graphing meter or scope on a long time base. Yes, you can use a test light and lab scope to check a tail lamp.

Min/max on a meter would work too.

 

[SuzukiGS750EZ]

I should have been more clear but when I said he's not electrically savvy, I meant he'll be using it for testing fuses and checking for power.

On the other side of things, the people whom say the powerprobes aren't safe tools, so are test lights theoretically. If somebody has seen one used and the person they saw used battery ground to check for voltage and said uneducated person hooks up to power...

A powerprobe should only be used as far as one's knowledge. I don't poke circuits i know nothing about and most two wire components that actuate in some way, I'm comfortable applying power to. Though... I normally use it without applying the rocker switch.

 

[2ndGearRubber]

I should have been more clear but when I said he's not electrically savvy, I meant he'll be using it for testing fuses and checking for power.

On the other side of things, the people whom say the powerprobes aren't safe tools, so are test lights theoretically. If somebody has seen one used and the person they saw used battery ground to check for voltage and said uneducated person hooks up to power...

A powerprobe should only be used as far as one's knowledge. I don't poke circuits i know nothing about and most two wire components that actuate in some way, I'm comfortable applying power to. Though... I normally use it without applying the rocker switch.

A test light can limit current, the power probe will dump 10amp? Into a circuit before the breaker pops.

I'd get him a test light with the smallest bulb you can, to minimize current flow. If you want to be fancy connect it across the battery and measure the current.

 

[American Locomotive]

Just get him a test light, and a cheap multi-meter and show him how to use both.

A PowerProbe is a very useful took, but you can blow things up real good if you don't know what you're doing. I wish they'd make a current-limited version.

 

[SuzukiGS750EZ]

Just get him a test light, and a cheap multi-meter and show him how to use both.

A PowerProbe is a very useful took, but you can blow things up real good if you don't know what you're doing. I wish they'd make a current-limited version.

He's got a fluke meter already, set him up with no current measurement. Just a pocket meter.

 

[richfinn]

he's got a fluke meter already, set him up with no current measurement. Just a pocket meter.

otc 3633!!!

 

[SuzukiGS750EZ]

otc 3633!!!

I got the 3636!

 

[richfinn]

I got the 3636!

It will be good quality, I had to import my OTC 3633 to the UK from AESwave cost me a frickin' fortune

 

[plinker]

Sure a meter is better for VOLTAGE checks, but a test light will show that the circuit can carry a certain amount of CURRENT. It is very possible to have voltage, but insufficient current in a circuit.

Additionally, an incandescent test light can be used to LIMIT current to device when placed inline.

Agreed, That's why the test light, PP3 & fluke meters all have their place in my electrical drawer. Some "custom" stuff for bulb tests too. I've had a fuze show voltage before on a Mack GU, but it failed to light the test light.