Voltage drop testing a parking light/turn signal circuit (Part 2)

Рет қаралды 24,263

Күн бұрын

This is a review of the wiring diagram and reactions of the test light and circuits. Here is the video this is based on • Voltage drop testing a...
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Пікірлер: 136

@jamesd2482 4 жыл бұрын

Someone said before how they appreciated the videos you guys make as a diy person on a budget trying to keep their vehicle and wife's car on the road. It means a lot to people like us and I have personally seen success. I hope the good returns your way, thanks.

@ScannerDanner 4 жыл бұрын

It has my friend. Especially with comments like this

@detailedautodiagnostics 2 ай бұрын

EXCELLENT FOLLOW UP!!! Showing my students this tonight ..pure gold my friend!!!!

@robertmedina6875 4 жыл бұрын

I understand so much more than I ever have before about electrical diagnosis. I have studied hard on Scannerdanner Premium. It makes videos that you post so much easier to understand and enjoy! Yesterday using the fundamental principles taught on Scannerdanner.com I was able to figure out and electrical issue on a 2004 Ford Taurus. Before joining the the premium website I was not able to do electrical diagnosis beyond basic meter reading. Thank you going out to you Paul and Caleb Danner!

@ScannerDanner 4 жыл бұрын

Will you post this on the feedback page of my website? www.scannerdanner.com/leave-read-feedback-new.html

@kirkwest6654 4 жыл бұрын

Best youtube Tech around.... Gets up to work everyday and shares his knowledge.. I am grateful! Thank you Paul!!!!

@justincognito201 4 жыл бұрын

I NEVER have allowed notifications to anyone’s yt channel or commented for that matter, before but you know your business. I’m in tech school in NM and love EVERY video I’ve seen of yours thus far. Keep up the amazing work.

@ScannerDanner 4 жыл бұрын

Love this comment!

@mechanicseyeforthebackyard420 4 жыл бұрын

Paul is a genius! I love how he knows that not everyone has endless funds to buy test equipment. He shows ways to diagnose complex driveability problems with a test light. A test light!!!!!!!

@basharalqasim1264 4 жыл бұрын

Dear Paul If only 5% of the world population follow your approach, sure we will live in a better different word. Thanks for the brilliant presentation

@martinguitarhd28 4 жыл бұрын

Caleb cracks me up with his comments he is very witty. Cheers

@ScannerDanner 4 жыл бұрын

he gets it from his mother for sure lol

@mostlymoparih5682 4 жыл бұрын

@@ScannerDanner Shhh she might be listening.

@CumminsDriver100 4 жыл бұрын

@@mostlymoparih5682 He's a total goof lol.

@kenniefernandez 4 жыл бұрын

Hey Paul ,Kennie here greetings from Puerto Rico my friend!!!!!. I know this is not the topic ,but i just want to share with you a very important find that after alot of research and calculations with couple of different car brands i made a conclusion,is about MAF SENSORS if i remember in some of your videos you check maf grams per second at idle by comparing engine displacement to it on a 1:1 ratio,thats good ,but after a lot of test on couple of cars that i was troubleshooting new and old ones ,i did some calculations and the results are spot on, you just have to multiply the engine displacement liters times 1.65 and you get the exact desired maf measure at idle for that particular car thats + /- 5% :),just want to share that knowledge with you, bless you man ,ive always watch your channel and like the videos ,good job keep doing it ,God bless you my friend!!!!!!!!!!

@the1coolkidd 4 жыл бұрын

Wow truly AMAZING! It’s still hard for me to visualize these circuits and I can be left with a blank stare at times so these thorough breakdowns are really a blessing PD!

@blockequals4 4 жыл бұрын

the1coolkidd Amen!

@nelsonnarciso1791 4 жыл бұрын

I think you explained it well. Considering that was not even the car you where suppose to be working on.

@abonourabonour1006 4 жыл бұрын

You and your son spend a lot of time and effort to educate people you do not know and also for free. of all I can say God bless you

@billyyoder8171 4 жыл бұрын

Thank you Paul and Caleb. Good job. Have a blessed and safe week.

@SmittySmithsonite 4 жыл бұрын

Nice follow up, Paul. I've been playing around with 12v systems for so long, I sometimes forget that people might not know how an old school flasher works, or how the BCM of a modern car does the same thing. That was an "ahh-ha" moment for me there - I always assume everyone knows the basics, but not everyone does! They're lucky to have you on the net here, Paul, to teach them. 👍🍻

@8953147 4 жыл бұрын

Great Section 1 material review using real world problem! Thanks Paul and Caleb for the refresher- love your book, by the way!!!

@xristosmaglaras7077 4 жыл бұрын

ONE OF YOUR BEST VIDEOS EVER...EXCELLENT AS ALWAYS PAUL...THANK YOU SO MUCH..

@blockequals4 4 жыл бұрын

I had a reasonable grasp before. I can actually explain this to someone if I needed to now. Thanks for the extra, and for both of you investing your time.

@gaad7938 4 жыл бұрын

Man, you never fail to amaze me! Great diagnosis on a "simple" problem (which is not so simple). Great teaching moment.

@victorlewis8970 4 жыл бұрын

Thanks again, SD for this 2 video, I'm hungry of all this information. Thank you.

@nickayivor8432 2 жыл бұрын

Good Evening ScannerDanner take care and have a great day ScannerDanner God bless you ScannerDanner 👍 🌟🌟🌟🌟🌟🌟🌟🌟🌟🌟 GREAT TUTORIAL THANK YOU VERY MUCH HELPFUL VIDEO 🌟🌟🌟🌟🌟🌟🌟🌟🌟🌟 From Nick Ayivor from London England UK 🇬🇧

@vin605 4 жыл бұрын

Thanks really appreciate your explanation, i would love if you use this way of explaining every now and again going forward, as for most of us learn very well visually

@Autorepairtechs 4 жыл бұрын

Great job as usual Paul I always like to check out your videos to gain more knowledge as a technician keep up the good work

@wyattoneable 4 жыл бұрын

Wow, you did some great editing for this one, thanks guys.

@High_Tech_Mountain 4 жыл бұрын

Very thorough explanation for those that didn’t fully comprehend in part 1 it could definitely be confusing! Scanner Danner, as always. Thank you!

@VashthStampeede 4 жыл бұрын

A perfect explanation of circuit behavior. Love your videos! Out here in the west, we call the rear parking lights taillights.

@ScannerDanner 4 жыл бұрын

lol, yeah, I guess we do too :-) Thanks man

@Gatopanzon_1976 4 жыл бұрын

Just did an intake manifold on a 300, runner problems seems very common on this engines. Very good videos! great way to keep those diagnostic skills fresh! Thanks!!

@gearstil 4 жыл бұрын

Thank you for these detailed explanations!

@RotoRCol 4 жыл бұрын

he is a real tech professor , now I understood everything, thank you for your time both guys song and dad, I would have liked that you had been me teacher at college tech

@stationaryenginesworldwide 4 жыл бұрын

No grounds on circuit can create some crazy things on other circuits that share the ground...thank you Paul and Caleb ...great video as always and a great demonstration of the circuit and what it was doing

@baxrok2. 4 жыл бұрын

Thank you both for reviewing this diag and circuit! This was a fantastic demonstration and explanation. It really helped.

@ScannerDanner 4 жыл бұрын

great! that is what I wanted to hear, thank you

@simonilett998 4 жыл бұрын

Thanks Paul, a fantastic update + clarification to the related case study. It was all pretty self explanatory once you tracked down that broken ground (or 2) Backfeeds and missing grounds obviously cause some very odd, and often confusing issues....finding a diagram, or pulling it out of our head and putting it on paper always helps to get ones head around these quirks of electrickery👍

@hpelisr 4 жыл бұрын

Resistant drop making them dim, the path to ground is pulling the power down. I like your videos,great work.

@daveg6220 4 жыл бұрын

For me you did a pretty good job explaining on part 1, that being said your are the best on the interweb at explaining circuits to make it crystal clear. Wish I could have taken your class 30 years ago!

@ScannerDanner 4 жыл бұрын

I actually thought so too, at least good enough to understand what was really happening, but for some it wasn't clear enough and when I went back to look at it, I thought I could improve what I showed, so I figured I'd do it. Thank you Dave

@liviudaniel5082 Жыл бұрын

good lesson.tjhanks Danner team!

@martinguitarhd28 4 жыл бұрын

Thanks Paul for uploading. Might seem basic to some but I learned from this even though I subscribe to the premium channel. Any one thinking of trying out the premium channel will not be disappointed it is a fantastic learning opportunity for a great value.Thanks Paul.

@ScannerDanner 4 жыл бұрын

Thank you so much!

@ScannerDanner 4 жыл бұрын

A neccessary review of the wiring and the back feed and the tests I showed. I definitely could have explained that part of the original video better.

@tpcoachfix 4 жыл бұрын

The current will always follow the path of least resistance to get from one side of the battery to the other. In this case the current had to travel through the filaments of the other bulbs.

@mikechiodetti6737 4 жыл бұрын

You done good! I've seen this many times, but you've done good! It's better to explain the theory and the results of the diagnostics away from the vehicle. It just makes things easier. Once the person understands the theory by seeing it on the board or paper or whatever's used, when the application is applied to the problem vehicle, the results are better understood and the tech knows what to look for the next time. I hope that makes sense.

@Pablo_Automotive 4 жыл бұрын

Thanks for second part Caleb and Paul :-)

@billyr9840 4 жыл бұрын

Paul, had the same scenario with my dodge ram but but much simpler. Right headlight lost its ground and found one thru the left headlight. Resistance in the left bulb made the right bulb dim. Did your famous unplug it test ( LOL ) of the left bulb and the right bulb went out. Put a test light connented to bat - on left side ground and found 12 v . At first you go uuuuh ? But if you break out a wiring diagram like I did it all makes sense ! I have been taken your classes for many years and people it was and still is, money well spent. And to top it off cheap ! Paul good to see ya teaching you son and good to see him taking a intrest. As a added benefit which I'm sure you know it gives you opportunity to spend time together. I always said you are a automotive god ! LOL ! Take Care !

@hddm3 4 жыл бұрын

Your boy is you just younger lol. Great team. God bless your family man!

@carlosmaurencig6763 4 жыл бұрын

Great electrical class!

@cwj9202 4 жыл бұрын

Both videos were superb. When the crazy light issue presented itself, it was obvious to me there was a defective ground in the parking light circuit for that LF side; however, I was initially bewildered by your use of the term back-feed, but I understand your reasoning behind it and may use that approach in the future, if my normal explanation of the circuit finding the easiest path to ground through other light bulbs fails to illuminate a fellow mechanic's cerebral light bulb.

@user-io3hw7hx7q 4 жыл бұрын

Awesome outstanding job have a great time thanks

@joopterwijn 4 жыл бұрын

Hahaha, sorry had a mayor 😂 around your teaching moment! I understand it always hard to be clear, this was not the ☀️ moment. Tanks for the update,... keep us smiling!

@ScannerDanner 4 жыл бұрын

so you are saying the update was not the moment? or the original explanation :-)

@joopterwijn 4 жыл бұрын

ScannerDanner the original was fun to watch, the second or update was kind of better. Personally I think first that a simpler diagram with two lights would explain the situation with moving ground easier en more clear. Than increase the diagram with more light two show the basic is the same. And he I’m not a teacher but I love KISS 🤪 love the vids! And thx to Caleb for helping you out!

@richardcranium5839 4 жыл бұрын

so left turn runs a post and the park does a sitdown between the safeties. pulling guard as a blocking scheme for the fake end around. got it ! lol good of you to revisit it!!!

@ScannerDanner 4 жыл бұрын

hahaha yep, that's about right

@paulbradley9912 4 жыл бұрын

Well explained.

@adilmchichou5710 4 жыл бұрын

I gotta watch it again

@PaulCTownsend Жыл бұрын

Thank you

@muresanioan7130 4 жыл бұрын

thank you

@jamesgann560 4 жыл бұрын

thank you so much for these videos! i have learned more from you than i have from any other youtube channel! Would it be possible to present you with a topic? I have a 92 miata and it has power / idle problems. Id love to learn more about diagnosing performance issues on pre OBD vehicles. anyways, keep up the amazing work!

@ScannerDanner 4 жыл бұрын

James, thank you so much! I have a forum on my website that is free to join where you can definitely get some help with your problem and some education along the way. It is free to join as well, hope to see you there www.scannerdanner.com

@jelotech579 4 жыл бұрын

Nice bro

@richardwecker8322 2 жыл бұрын

great!

@thisisanaltthisisanalt3948 4 жыл бұрын

Hi!! ( This isn't really my Name and such. ) But my Dad watched your Videos and sometimes I do to.

@masterfastermasterfaster 4 жыл бұрын

Caleb, you scared us!!!!

@ScannerDanner 4 жыл бұрын

why is that? must be missing something

@CumminsDriver100 4 жыл бұрын

@@ScannerDanner I'm assuming the glasses and earrings threw some people off, as this in their mind is "gay". But so what if he is? That isn't what should matter...

@stspringer2003 4 жыл бұрын

Good morning Paul, just for my learning experience I set up this circuit on a breadboard and I found that, on-time line starting at 4:20 of this video, with the ground disconnected, the single parking bulb is blinking and dim, but on the dual filament turn signal bulb, the parking light filament is the one that is actually blinking and dim, not the turn signal filament, that filament is off totally. Does that make sense to you? Thanks

@jkbrown5496 4 жыл бұрын

If you pull each filament out as a resistor of value, R, into a simplified resistor circuit diagram, you end up with the following when the turn signal is on and the bad ground: ( I assume the same resistance, R, for simplicity) R - turn signal filament 2 R in parallel - LF parking light filaments 4 R in parallel - other parking light filaments through which ground is found That simplifies to a series resistor circuit after you calculate the equivalent of the parallel resistors of : R + 1/2R + 1/4R R + 1/2R + 1/4R = 1 3/4 R as current is constant voltage drop for each R in a 12 volt circuit is 6.8v So our voltage drops across the equivalent circuit are 6.9 + 3.4 + 1.7 The voltage drop explains the dimness and why the other parking lights are visible as most 12v bulbs are not "lit" at such a low voltage.

@kylesherrisalkintrent7828 4 жыл бұрын

Hey paul I got a ? For you I have a 2012 Buick with a 2.4 codes p0010 p0013 For the vvt solenoids want to check circuit integrity there 2 wires each but both are low ref and go to the ecm are they how would I tell witch one is ground witch is power? Do they alternate depent upon state help Please

@rahrah8076 4 жыл бұрын

Hey Paul!! You know what would work good for you’re go pro and cameras..order some Photography Close-Up Macro Filter Lens..

@johnworkman5121 4 жыл бұрын

My verus scanner which I bought used off the snapon truck ...I’m having trouble scanning a fiat

@ericjudd3137 4 жыл бұрын

Like the new video it's a easy fix sometimes you can make things to complicated than it has to be love the videos I just think you drug this one out to long

@ScannerDanner 4 жыл бұрын

This explanation was for those who wanted me to break it down like this. I understand that this isn't for everyone, but if you really wanted to know the "why" part of it, then this one is for you.

@rimmersbryggeri 4 жыл бұрын

Just wanted to ask. Is there any reason not to use a nomal lab scope for automotive applications. Like a Rigol, or a UNI-T.

@ScannerDanner 4 жыл бұрын

it is a good question and unfortunately one I am not an expert in, join my forum (it is free) and post this to my community, I promise you will get some great answers from a super helpful and friendly community www.scannerdanner.com Thanks!

@joachimjohan1215 4 жыл бұрын

AWSOMMM!!!!!!!!!!!!

@richardwecker8322 2 жыл бұрын

all other blinker/hazard work except DSFL dash is good

@richardwecker8322 2 жыл бұрын

I have the same situation but the blinkers don't work but the parks work new flasher ...new bulbs

@spiritualcramp8000 4 жыл бұрын

why do i have severe voltage drop (14 to 4) on some utency (turning lights, stop lights, int. fan ) and none on others ( head l. hi beam, board l. etc.)? engine on or off no difference. please help i'm getting mad.the turn light drop is weird: voltage pulsing 4 - 14 as light pulses On Off.

@leebulldog87 4 жыл бұрын

A Dry- Erase board with different color markers would work great.

@ScannerDanner 4 жыл бұрын

didn't have that option today, sorry, I thought this was better than what I did in the original

@MrTwisted1977 4 жыл бұрын

The best thing about all ur diagnosis compared to others is the fact that u tend to go the full hog on explanations using easy to understand diagrams.well done.AGAIN!

@ScannerDanner 4 жыл бұрын

@@MrTwisted1977 thank you!

@vincedelpezzo8209 4 жыл бұрын

Following when you break it down.

@adilmchichou5710 4 жыл бұрын

Hello scanner danner why you stop shooting videos we have learned a lot may be I gotta subscribe in your website channel

@srigokulnath8507 4 жыл бұрын

Sir one question. What is your instinct about futer vechile. Will the ic engine still be there or some other technology will evolve or existing technology like electric, fuel cell vechile will get advanced up to the replacement of ic engine in that circumstances what will be the future of we as a technician because personally i been in this field for these many days and gain considerable amount of knowledge on ic engine diagnositics especially more from you. If suddenly things are changed what will be the future of today's technician and also the maintenance is much lesser in electric vechile than ic engines so that vechile coming to us will also reduced, I hope you understand my question

@childerstodd 4 жыл бұрын

Will shorted 5v reference circuits always cause loss of comm. with pcm or no data stream?

@ScannerDanner 4 жыл бұрын

If there is only 1 regular, yes, absolutely, every time. Today's cars are using multiple 5v regulators

@childerstodd 4 жыл бұрын

@@ScannerDanner I have a verus edge scan tool and I have never used the scope until just recently. Do you do any instructional videos on it? I've watched the Snap-on ones but they aren't very good. Thanks.

@ivandrago2557 4 жыл бұрын

Hello, can I ask a question not related for this video. On VW polo 2000 year, 45 kW, 4 cylinders had failing injector not opening. It had upstream wideband o2 sensor, at idling scan data showed 1.52 V when all four injectors worked. After failing on off injectors it showed 2 V meaning rich condition. Is it possible that ECU performed longer time for opening injector causing rich condition. Can other three injectors stay that long opened causing rich condition Mladen from Croatia

@ScannerDanner 4 жыл бұрын

you are saying you had a rich condition from one injector not working?

@ivandrago2557 4 жыл бұрын

@@ScannerDanner exactly

@ivandrago2557 4 жыл бұрын

@@ScannerDanner I spoke about it with techician and he said that other injectors had longer time open cuasing rich condition

@ScannerDanner 4 жыл бұрын

This would result in a lean condition and a +25% fuel trim from one injector not firing on a 4 cylinder engine

@ivandrago2557 4 жыл бұрын

@@ScannerDanner I know it should so I am confused. I could try duplicate a problem, like I mentioned before o2 sensor showed rich on scan data, think fuel trims were ok. I will look injector on time , fuel trims, o2 upstream and downstream and inform you if You like.

@bilalpakstni9704 4 жыл бұрын

😃😃😃😃😃😃

@manne3228 4 жыл бұрын

I honestly thought that Caleb was his daughter because of the earrings. Love your vids scanner danner.

@ScannerDanner 4 жыл бұрын

why? you've never seen a man with earrings before lol

@throttlebottle5906 4 жыл бұрын

I think you should have used actual sockets, bulbs, etc. and a battery or power supply. why do I suggest that? from what I recall of school(long ago) drawings and scribbling were fine for me, but others needed to at least see the stuff physically working to actually learn and grasp it, some even needed actual hands on time. some of which have moved on from electricians into electrical engineering.

@animalinstinctgaming 4 жыл бұрын

Lincoln MKZ 2008 - Parking Lamps keep blowing instantly. What could be the issue? A bad ground or something??

@ScannerDanner 4 жыл бұрын

parking lamp fuse? or the bulbs themselves?

@animalinstinctgaming 4 жыл бұрын

@@ScannerDanner fuse 15amp, which is connected to the smart junction box inside the car.

@ScannerDanner 4 жыл бұрын

you will need a good wiring diagram to be able to find out what all runs off of that fuse This is the DIY version of the diagrams and service info I use. It will run you $20 for your car eautorepair.adtrk.biz/?a=10817&c=24&p=r&s1=

@carstengotfredsen160 4 жыл бұрын

💪 🚗 ✔

@davidb.fishburn9338 4 жыл бұрын

Interesting. But, in a nutshell, it's an overcomplicated and drawn out way of saying something simple; electricity flows to a path of the least resistance. The open in the ground wire created infinite resistance, so the current found the grounds thru the bulbs which were of lower resistance than the open in the ground wire. Still interesting to see the diagram and the theory.

@ScannerDanner 4 жыл бұрын

over complicated to some, just what the doctor ordered for others :-)

@rechiebaniaga1784 4 жыл бұрын

chk orance wire newtral saftay sw

@fascistpedant758 4 жыл бұрын

@14:40 you forgot to consider current from the outer parking light. Just saying.

@ScannerDanner 4 жыл бұрын

the outer light was not a factor with the parking lights on, nor was it for this example :-) look at it close

@fascistpedant758 4 жыл бұрын

@@ScannerDanner Isn't it hardwired in a parallel circuit with the low intensity filament of the other bulb?

@ScannerDanner 4 жыл бұрын

@@fascistpedant758 with the parking lights on that outer bulb has a 12v feed and basically 12v on the ground. It is not a factor as to why the turn signal circuit is being illuminated by the parking light circuit. My arrows tell the story too

@fascistpedant758 4 жыл бұрын

@@ScannerDanner I'm sorry, maybe I wasn't clear. I was referring to your explanation of the circuit feeding the test light. My point was that, given that the outer bulb and the low intensity filament are in a parallel circuit, the outer bulb would see the same voltage drop and therefore also contribute to current flow through the high intensity filament and the test light.

@ScannerDanner 4 жыл бұрын

@@fascistpedant758 got it, sorry, I had to draw it out again lol, you are correct, that leg is effectively dividing the resistance of the parking light circuit in half and is a contributing factor on the brightness of the test light bulb. In fact my arrows are WRONG on that leg of the circuit smh. Thanks man, but I really don't think this piece is important. That circuit is already super low ohm compared to the test light and I would put money on that test light bulb brightness not even changing (to the eye) if I disconnected that outer parking light.

@mostlymoparih5682 4 жыл бұрын

I am a bit confused with the position of the test light in your schematic at 10:52. I can see how the test light would light but not the parking lot. Did the parking light also light? If you simplify the circuit so that the parking switch goes only to the parking light and then right to an opened ground it appears to me that the parking light would only light if the test light is connected to the yellow leg of the circuit before the open ground. The parking light would not light if the test light was connected to the red leg of the circuit. What say you Professor? I have rewritten this question a few times, hope I explained myself clearly.

@ScannerDanner 4 жыл бұрын

No, the parking lights on the LF were never lit by themselves, only when the turn signal circuit was on and the parking lights were off, did we get a back feed through those parking light bulbs. I hope I'm answering your question. Let me know. This can be confusing for sure.

@mostlymoparih5682 4 жыл бұрын

@@ScannerDanner Thank you much sir. You're the best.

@adilmchichou5710 4 жыл бұрын

I am lost