Voltage Drop Testing with a Test Light? [Part 1]

Of course a test light is not always the preferred tool when performing voltage drop testing, but when you have an output (electric motor, solenoid, relay etc) that is not functional at all, a test light is just as accurate as a voltmeter, and can even be more accurate in the case of an open in that output (no current flow).
When we want an actual number (voltmeter), is when we have an output that functions, but not properly. For example, a starter motor that turns, but turns slowly. In this case, the test light is NOT the preferred tool. Voltage AND amperage measurements would be needed for a proper diagnosis.

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[ScannerDanner]

Of course a test light is not always the preferred tool when performing voltage drop testing, but when you have an output (electric motor, solenoid, relay etc) that is not functional at all, a test light is just as accurate as a voltmeter, and can even be more accurate in the case of an open in that output (no current flow).
When we want an actual number (voltmeter), is when we have an output that functions, but not properly. For example, a starter motor that turns, but turns slowly. In this case, the test light is NOT the preferred tool. Voltage AND amperage measurements would be needed for a proper diagnosis.

[stevendenis]

Dan, as a ASE master tech of over 45 years and an automotive educator for almost 30, I have learned that you can lead a horse to water but you can't make 'em float. Your original video was perfect and showed the concept in the best way possible. If people want to claim "foul!", just let them. It's their loss. Ignorance and arrogance is not a winning combination. Let them flail, let them fail. You can't fix stupid. You help a lot of people. Keep up the good work.

[JohnDoesGarage]

I watched that video and was really impressed how well you demonstrated voltage drop using a test light. If anybody has an issue with it, even if they claim to be an "expert", then they have no clue what voltage drop is.

[nwmartinzz]

It’s just to show you that you can do it if you’re in a sticky situation with just a test light or just a multimeter it can be done 😊 Thank ScannerDanner

[Francoperez]

Good morning Paul.. This video was not boring at all.. The voltage drop test that you teach has help me in alot of the test i have done for many cars.. And everything that i have learn its has been from you.. I am saving money so i can buy your book and pay for the premium channel as well. Thanks from Franco Perez.. Mexicali, Baja California Mexico...

[eliseozuniga]

That heat shrink repair with the liquid tape had me cracking up 🤣🤣🤣🤣, That first horn repair looks like all my diy projects. I can’t wait until your test light comes out, I’m buying it the first day it’s out.

[MichaelBennett-runu]

Those so called experts obviously aren't mechanics. I started doing that back in the 80's and have made lots of money and lots of good customers. Keep up doing what you do.

[gto]

You are the best at this and a great teacher.

[Tony-rlfr]

LOL! Paul can't be driving around with no sissified high note, Fiat sounding horn yo! 😂

[josephespinoza]

Your right on learned this in collage 40 year's ago

[thestoryteller]

the best trubulsooting video on YouTube was that sarter video. 🔥voltage drop in 4k

[codo]

Paul, you could thin that electrical liquid tape with acetone.

[stitchbmx]

The bee was just going to ask you about your extended warranty.. haha

[xephael]

6:59 shouldn't you give him a refund on the horn part if it turns out to be a connector issue? Bill your time but not the part because you didn't need to replace the part... Charge for the connector if you need to.

(Edit)
9:30 .... Glad you covered that you shouldn't charge them for the horn if it wasn't needed.

[JamesSmith-xssr]

You can rejuvinate semi dried liquid tape by placing the container inside a cofee cup with HOT water, let it heat for a few minutes. I keep partially used cans inside a ziplock freezer bag...

[keithbland]

You are a better person than I, you can show the test and you will find someone who don't believe in facts. It's goes against there belief or alternate facts. And what's really hurtful they are mechanics who supposed to do this for a living.

[tonyt]

Always love your content Danner! It's there anyway to pay you for remote assistance diagnosing issues? I own a repair shop and have always wished there was an easy way to contact you. Thanks sir! Side some sexy bots in the comment section. Lol

[xephael]

13:26 don't use a lighter.. use a small propane torch where you can control the heat better as you rotate it. The best way to do it is to use a heat gun

[firstlast---]

I thought that starter video was a textbook perfect demonstration of voltage drop

[Pablo_Automotive]

Thank you so much for another great video team Danner =)