The Best Way To Find A Shorted Circuit!!

Finding a shorted circuit can be nerve racking. But with this easy method, you will save your self a bunch of money on blown fuses and time spent trying to locate a failed circuit!
Equipment used:
www.jarheaddiag.com/shop/p/sh...
www.jarheaddiag.com/shop/p/hi...
Merch:
www.jarheaddiag.com/shop/swag

[@rscelectrical7091]

Great clear video, been using the same method for years and it works like a dream.

[@Sparky-ww5re]

Nice video. I learned from an old school electrician many years ago, a similar trick to finding a short in your house. If you have edison base fuses (glass fuse with an E26 base, what most household light bulbs have) remove the blown fuse and insert an incandescent or halogen (preferred) or dimmable LED bulb into the fuse socket. With cartridge fuses, use a lamp socket with leads and alligator clips across the cartridge fuse, with power turned off when connecting them. With circuit breakers, wire the lamp socket between the breaker, and the circuit in question, then turn on the power. A short circuit will light the bulb to full brightness. When the problem is located and repaired, the bulb will turn off, or light at a lower brightness if there are still loads connected, the larger the load, the brighter the bulb. Do not operate the circuit with a light bulb in series for more than a minute or so, because some appliances particularly those with motors, can be damaged if ran at reduced voltage for an extended period.

[@JarheadDiagnostics]

Nice!

[@kylen1922]

​@JarheadDiagnostics So I have a tractor im trying to find a hot wire shorted to the Frame. It has not blown a fuse. I have spent hrs trying to figure this out. When U use the battery disconnect the entire tractor Frame,engine any thing that's metal has 12 volts. Any suggestions?

[@Sparky-ww5re]

@@kylen1922 assuming you were unable to get a approximate location of the short by sight, sound smell, (smoke, arcs/sparks, burned plastic) you should be able to isolate the short to a particular circuit connecting a 12 volt test light in series between the negative battery terminal and the negative cable. A short would light the bulb to full brightness, a high resistsnce short that doesn't draw enough current to blow a fuse will make the test light slightly dimmer. In either case, start removing fuses, one by one, when the test light goes out or considerably dimmer, you just found the shorted circuit. You can then inspect for faulty components on that circuit, and check for any areas where the wiring may have rubbed through and touching the chassis.

[@kylen1922]

@@Sparky-ww5re I appreciate your response. This tractor is a electrical nightmare lol. It has 6 fuse boxes and 3 computers. I've un hooked all the fuse boxes with no response. And have checked the hot wires from battery to cab. So I'm about to throw in the towel. Thought the battery's had reverses polarity ..nope. alternator starter ....nope. It's low resistance short so think I'm going to just let it go. Have way to much time into it.

[@carburetedcowboy4288]

Amazing work! I need to get multiple products for my shop! Thanks for creating amazing products for technicians!

[@simonilett998]

Nice one Brandon. For a switchable load test light, I made up a set of 4 switches connected with one common positive wire from a single banana plug parallel linked to each switch input terminal, then from each switch output I can individually control a set of 3 globes of a tail light harness I pulled from a junk car, this gives me 4 switchable filaments, and a common ground wire shared by all the globes. I can essentially choose an appropriate load via the 4 switches for most integrity testing, harness shorts etc at the fuse box or pretty much whatever by adapting to the 2 banana plugs to suit what I need. I can then choose a low, med, high, or even higher amp test light, or combination. As an audible tester, I have a 12v car horn and a small piezo buzzer, both with a pair of test leads terminated with banana plugs, which have been super handy for testing circuit integrity or short finding etc when it's not possible to see the test light👍

[@JarheadDiagnostics]

We have seen the set ups with multiple bulbs and a switch for them. It is an excellent idea.

[@bernardocisneros4402]

How much is each load, Amp wise?

[@simonilett998]

@@bernardocisneros4402 I haven't tested the 12v horn amp draw, but the tail light harness has 3 bulbs, 4 filaments. One bulb is a dual filament 21w/5w stop/tail, as well as one indicator bulb and one reverse bulb (2×) 21w. At 12v the 5W filament should draw a little under 417mA. The 21w filaments should draw around 1.75A each. All running together that comes to a little under 5.67A, so that's around 670mA more than a 60w H4 halogen headlamp bulb at 12v👍

[@bernardocisneros4402]

@@simonilett998 Thanks for sharing the info

[@AbbottAutomotive]

This is one of, if not the best method in my opinion. 👍🏼

[@JarheadDiagnostics]

We totally agree!

[@advancedleveldiagnostics]

I agree it's by far the best way to track shorts, especially intermittents, because you can wiggle the harness and see where it's shorting. Thanks for sharing!

[@JarheadDiagnostics]

Totally agree!

[@Chatchie007]

Im super stingy with my subs but you deserve it man. Troubleshooting is becoming a lost science. All we have are a bunch of 'parts changers' out there. Keep up the good fight, hope your hourly rates reflect your knowledge.

[@Mr2004MCSS]

Nice video and great idea. I just ordered this box and a few other things.

[@JarheadDiagnostics]

Thank you sir! Just a reminder, that added you in to win the diagnostic cart.

[@Mr2004MCSS]

@@JarheadDiagnostics Nice.

[@80SWoods]

I would LOVE a step by step video of making these test lights and an explanation of what size bulb(s) to use for what sorts of issues. This is all fascinating to me.

[@JarheadDiagnostics]

We offer these on our website. Link is in the video description.

[@mandytuning]

An 1157 bulb, socket,banana jacks, cap of spray can, ,will have .6amp in one filament, 2amp in the remaining filament. Or combine it.i also made one with a h4 bulb for higher current test

[@davidche554]

Nice simple video Whered you get the box

[@thebaldmechanichardatheari1124]

Very simple idea but very effective. Good work 👍

[@JarheadDiagnostics]

Thank you!

[@jgeorges3061]

AWESOME THANKS FOR SHARING.

[@JarheadDiagnostics]

Thanks for watching!

[@patrickmazzone9066]

Excellent tip thanks good to know

[@JarheadDiagnostics]

Glad to help

[@Quickwrench75]

Great video Broke it down made it simple Basically in some kind of way made your own powerproble short finder. I been doing your way for years. Just never added sound to it.

[@JarheadDiagnostics]

The added sound will help out for those hard to See locations.

[@bernardocisneros4402]

Great video, idea, and explanation. Very easy to understand and follow. Thanks! Is this what you did while you served or did you take this up after you got out?

[@JarheadDiagnostics]

I was an aviation maintainer. My MOS did a little electrical, but must would be sent to the avionics shop.

[@bernardocisneros4402]

@@JarheadDiagnostics I was an engine and propeller mechanic on C-130. MOS 6016 & 6026 in MCAS El Toro, CA from 1988 to 1992 with VMGR-352. They're now in Miramar, CA. Which aircraft did you work on and which base were you at?

[@james10739]

I don't think i have really ran into anything like that where it was a problem like that would blow the fuse immediately but its a used trick to keep in my back pocket

[@JarheadDiagnostics]

Always have a stash of multiple test plans.

[@jaywyatt7476]

Did you 3d print that light socket, I was thinking of doing that same exact thing. And yes your way is different, but it’s so helpful to see the same job through a different lens. Thanks man.

[@newsflash7970]

replacement automotive socket, any parts store....

[@sheerwillsurvival2064]

Fantastic video love test light test

[@JarheadDiagnostics]

We do as well. Loading a circuit gives you much more information than just a meter.

[@BestMoblieMechanic251]

Been doing it this way for years 💪 great tool how do I order???

[@anthonyrosa4388]

if that audible box comes with a volume knob SOLD!!!!!! great job!!

[@JonathanLozada]

Where are you located? I've had 20 different mechanics look at my tail lights and still can't figure out why the running lights on my liftgate don't work with my headlamps on. It's been so frustrating 😫

[@train4905]

Exellent😊

[@raymondromero4558]

I learned a lot from your video

[@JarheadDiagnostics]

That’s all that matters!

[@adrianovergara1784]

@@JarheadDiagnosticswhat light are you using for that test because I want to make one myself. Thank you for this video.

[@thelifescout8335]

Thanks for this Brandon. Btw how is your in employee doing who had that incident in the shop?

[@JarheadDiagnostics]

He recovered well!

[@sheerwillsurvival2064]

I still have to order the audio indicator very nice

[@JarheadDiagnostics]

They just went live on the website!

[@sheerwillsurvival2064]

@@JarheadDiagnostics get payed on 30th I’ll be ordering 👍🏻

[@alexandercalonia1438]

How to order ​@@JarheadDiagnostics

[@emailjayb]

Excellent! One thing I have seen is when the ground from the other side of the component on the circuit being tested is burned through no ground will be there to light up the test light.

[@alexandercalonia1438]

Where i can buy like that

[@JarheadDiagnostics]

www.jarheaddiag.com

[@jackspratt4343]

But identifying the duff circuit is one thing, what happens next. How do you trace the wires and find out what is actually happening ? Thanks

[@JarheadDiagnostics]

That would depend on the situation. Not every circuit is built the same.

[@Malahoko]

The next step is usually getting the power distribution and ground distribution diagrams, along with DLC and schematics for related circuits / components that you are having the problems with.

[@jackspratt4343]

@@Malahoko Thanks Malahoko

[@keithmoore2094]

We're to buy those tool it good way find short to ground

[@JimmyLewter]

Okay 1999 Nissan Altima the right side of the fuse box to fuse box in the engine compartment where all the links are at is inoperable The inside of the car there's like two rows that are working and two out of five rows that are working how do I find that short or that I'm sure that it's probably just what he said but I have a hard time comprehending the electrical stuff so can somebody help me out please please please this is killing me

[@anthonynicholls9415]

👍👍

[@michaelbox7285]

Wouldnt that only work on a dead short not a draw.

[@JarheadDiagnostics]

Correct. You would need something like this to help with a parasitic draw (if you want to use a scope). kzbin.info/www/bejne/qmHReXutqK6Ieqssi=cDcs3wdKtosy6VJ2

[@soptea]

I know a better way , put a 100 Amp fuse and watch for smoke !

[@mandytuning]

Why put a fuse? ,wire jump it😂

[@JarheadDiagnostics]

We personally use 0 gauge wire to jump the fuse. Don’t want to restrict the current flow. 🤣

[@joeandgod1]

Wherever the smoke comes out from is the problem, simple. Takes one minute.

[@galesams4205]

How many PCM have you fried doing this?

[@JarheadDiagnostics]

Zero, because I know how circuits work.