Also cooling fans on the electronics too, Mine also has steering, ABS, AC and Suspension pumps.

I have seen several vehicles take a half an hour or more for the computer to time out. One thing I started doing is run a jumper wire between the battery and the terminal in case my meter times out and it goes to sleep.

You usually have to wait at least 20 minutes, especially on a car that is suspected of having a power draw.

​@wearetheresistanceprepping1883 If your meter times out/goes to sleep, you can just turn it off and back on the amps setting without "waking the system"

@TimmyMill87 not so easy on the fluke 77. It must be turned off then back on and it will reset the system. It's just too easy to disconnect the cable then install a heavy enough jumper wire. That way you don't even need to leave the meter connected, just lay you leads on it from time to time. I've seen some f150s take a hour to time out.

heat gun

Good idea..

Omg. I love you smart people. Thank you. That's brilliant

Bruh why haven't I thought of this

I did the same thing on a BMW that wouldn't fully go to sleep. The problem as a communication module not sleeping.

Thanks for helping me friend, I sincerely appreciate it.

Hi there! did you put the relay on the b+ charge line going to the battery?

Hello Sir, can you help me to do this in my car I would like to know how you did the installation. Thanks in advance.

A new alternator might be cheaper than a proper 200A relay...

Anything thinking about this get a new alternator unless you have a 73

Learn scopes and you will be ahead than most technicians.

I also despise it. Not because it's unduly difficult. Customers just don't like paying for the troubleshooting.

That's because you don't make money doing electrical diagnostic they pay an hour for a 5 hour diag. Most tech know how to do it but on flag pay it's not worth it

@@scottcowen4071 if you're Bernie you charge 200 bucks, it may take 10 minutes but you gotta account for travel to the site time as well.

i like it

its all magic, when u see smoke rhe magic is leaving

Excuse my ignorance, but how can an alternator draw voltage if the power to it is off? I might have the same problem on my f-150.

​@@christorres2Could be shorted internally. They can't cover enough diag in a 60 second clip.

Alternators have ‘diode’ packs within them. Without going into a worm hole how everything works inside the diodes allow current to move one way, from the alternator to the battery.. if one of these fails when the car is off and the alternator isn’t charging the alternator will take ‘power’ from the battery.. draining it quickly in some cases. Newer alternators are complicated beasts but you can test them using a DVM.

Great points! I recently started using an OBD memory saver cable and a small auxiliary battery to maintain pre-sets, etc. Works great!

Yes! Especially on newer vehicles

there is intelligent life watching video's after all...

also close the doors with the battery cable on so the dome light cycles off completely.

​@@rupe53or leave them open and use a screwdriver to "lock" any doors you may have to otherwise open to check interior fuses..

All multimeters have fuses to protect the current measuring circuits, if too much current goes through it, all it does is blow an internal fuse. On the amps setting, its often a 5-10 amp fuse, on the milliamp setting its a few hundred milliamp fuse, depends on your meter. Measuring for voltage drop across a car fuse is nonsense, fuses dont have signficant resistance. If there is a voltage drop it means there is siginificant resistance across the fuse.

@@jumboegg5845​​⁠ I mentioned I didn’t have a clamp meter at the time - but you go right ahead if you think a fuse is going to protect your multimeter in this scenario. If it’s a $10 multimeter then what the heck eh - not forgetting the aggravation of changing the fuse - some are non standard so you’d have to order one unless ya bodge it to get a job done. You’re then hoping it actually went short circuit before zapping the multimeter - not nice seeing circuit board traces burnt to a cinder due to time for fuse to blow or LCD display gone due to voltage spike. Using more expensive multimeters most take precautions when using on ‘any’ equipment before sticking probes in/on. The voltage through fuses does work - it worked for me - & obviously works for others when watching those mechanic/creators on KZfaq that demonstrated it. It’s slightly more techy - with the different graphs for different fuse ratings - but one can get carried away as it’s not too difficult to find where the current draw is & what value one should expect. I’m ok with it. It’s not rocket science. I think this creator did a KZfaq on the voltage method 🤔 but may I suggest “Which parasitic draw test method is best” by FordTechMakuluko - he covers the bases - & precautions too. There are also isolating battery clamp terminals made with a switch to help protect the on/off scenario of probing with multimeters. They go some way to protect the multimeter - but I’ll make my decisions if/when faced with this scenario again. All the best! Happy diagnosing!

​@@messageobliquespe100 Its just how fuses work, a fuse very effectively protects the circuit from over current. If your cheap 10 amp rated multimeter can't actually handle 10 amps (because its poorly designed and overated), then always best to use a lower rated fuse (say 5 amps), to make sure it never works close to its maximum stated rating. The fuses in multimeters are special high energy ones, designed to protect you (not the multimeterr) against high voltage spikes of 1000 volts or more. This can only happen in general use if you are working on mains power, or if the car you are working on is struck by lightning lol. A fuse is a resistor, and because of its resistance, a 10 amp fuse for example will start to get hot and will show a significant voltage drop across it when it starts to get close to the 10 amps, slightly above 10 amps and it will get too hot and melt. That's how they work. So I suppose the voltage drop across a fuse might be useful sometimes, but the voltage drop would be very small, if like for example in the video the parastitic current draw was only 3 amps. 3 amps across a 20 amp fuse would show a tiny drop in voltage. I just went into my shed and put 12 volts 3 amps across a 10 amp car fuse, and measured a voltage drop of about 0.08V (80 mV) across the fuse. Thats very small, but I suppose it could be useful as a very quick check, but only if all other fuses show no voltage drop, and only if there is no legitimate reason for something to be drawing 80 millamps across that fuse.

⁠@@jumboegg5845 Thank you for your comments - all taken on board. Fuses can be effective in protecting the circuit from over current - but you’re at the mercy of the engineer that designed the circuit & specified fuse rating /quality adopted by the manufacturer. (I’ve been down this rabbit hole before - a 5 amp mini blade fuse in an expensive bit of kit that wouldn’t see much more than 1.7 amps at a push/fault when speaking to the service engineer. I imported & used 1 amp fuses - equipment been fine for years. I apply this rule to expensive electrical equipment - even domestic equipment - & down rate the fuse ratings where I feel fit / the need. Simple to take current draw readings from standby to switch on & select on that basis. I’m a bit precious of my Fluke multimeters they cost enough to warrant being careful with. With regards to your analogy of fuse breakdown - ie ‘slightly above 10amps & it will get hot and melt’ - fuses are more robust - can operate well above their rating for a number of hours. Blade fuses will carry on working for 100hrs at 110% of rating - 10mins at 135% - 5 secs at 200%. If there’s additional headroom given to the fuse adopted in the unit you can see how things can go south. I’ve not looked at the fluke fuse & its characteristics. I should put on the list but take for granted they knew what they’re doing so I’ve not bothered. “the voltage drop across a fuse might be useful sometimes” - glad you’re coming on board! The voltage drop is very small - we’re talking measurements in millivolts. In the Charts/tables you can read off the millivolt measurement for the fuse rating & see how much current is being drawn through the fuse/circuit. Search for blade fuse voltage drop on tinternet - Wordpress.com should come up This voltage reading is a measure for the current through the fuse. You can look up the current value in the table. From charts - for info:- 10A blade fuse: Resistance = 8.12milliohm. Voltage drop 116 millivolt -(I think this is maximum value of approx 1.4x fuse rating). For a 3A draw - through the above fuse - you should see a voltage of 25mV. (4A 33mV. 5A 41mV. 10A 82mV) To measure the voltage drop across the fuse, set voltage scale to mV - place the positive lead on one side of the fuse and the negative lead on other side. It takes seconds to do. When you see any value on the multimeter you will know there’s current going through as most circuits will be off or very little current being drawn - so anything greater than say a millivolts or two will stand out - & be a circuit to investigate. it’s a quick method - BUT note what the FordTechMakuluko on KZfaq covers. Hope you watched it 🤔 Approx values - for 1 millivolt:- for fuses:- 3A = 30mA 5A= 50mA 7.5= 90mA 10=120mA etc - Usual current draw in vehicles range from say 40-80mA when ‘shut down’ so over this can result in draining the car battery - which is what we’re trying to diagnose. Let me know of your further shed tests. Happy diagnosing! E&OE (I’m not in my shed)

​@@messageobliquespe100 Thanks for all that useful info, you put a bit of time into it. I know the maths and theory so probably wont need to look up the tables, but I am sure they will be very helpful to others reading this. Thanks for picking up on the milliamp "typo", yeah of course it was a voltage drop of 80 mV, not sure when that happened, must have been when editing to improve my expression. I've edited the mistake so its not there now. My experiment was quick and crude, just happened that the first load resistor I found was 2.2R 5W, was getting quite hot in my hands, quickly measured roughly 0.078V across the 10A fuse while holding it all together in my fingers, didn't bother measuring on the millivolt scale, was just after a ball park figure. Just realised my mistake, I initially limited the current output of the power supply to 3 amps, and forgot to unlimit it when taking the measurement. Just checked now and current draw at 12 volts is about 4.9A according to my cheap bench power supply, yeah I know that value is a bit low, when I want an accurate measurement I use a multimeter. In the video, the fault was showing 3 amp draw, which would stand out like a sore thumb. I have found 12 volt relays with corroded contacts passing something like 150 mA when they should be completely open (off). When standby current at the battery should be roughly say 50 mA, an extra 150 mA at the batttery due to such a fault takes many days to drain a good battery, not overnight. Using your values above for a 10A fuse, the voltage drop across the fuse due to a 150 mA fault would be a tiny 1 mV, and even less for 20A fuse.

memory on the radio / clock will also be a draw.

@@rupe53 also the PCM memory. That's where the 200 miliamps comes from.

@@gener.1253 ... yeah, I get it. I'm one of those old guys who did this stuff for like 50+ years. Glad I retired when I did.

@@rupe53 right there with you. Started in my dad's shop. ASE Master tech for over 40 years. I retired in 2017 but did my best to keep up with the technology until then.

@@gener.1253 ... going from memory, but recalling I started ASE cetrs back around 1978 or so. (NIASE?) I kept taking the tests till I ran out of time at the test centers. I did auto, machine shop, service writer, truck, (heavy and light) bus, school bus, carb, and EFI, body / paint, etc. People at that level numbered under 500 nationwide at the time. i was also certified as master tech by Nissan. I finally let them lapse around 2010 when they offered an extension (6 months extra) but failed to let me know when the next test date was. I said "screw it" when my employer didn't want to pay for it. Retired 4 weeks before Covid shut down the world.

Good eye! That is correct, I had the leads backwards in this video. With that said, the test works just the same and you would know that it is in fact a "positive draw" if that's what you were looking for in the first place. Thanks for your comment !!

You are Correct, I wasn't Being Critical. My Students get it Confused. With the New Electronics in the Industry today. Negative Voltage is Used In some Control Systems. You Video was Very Informative for A Technician I was Working With. I Appreciate Your Reply!

I came here to say this but yeah like he said any number higher than .50 you know something is wrong. This is exactly what was wrong with my Honda Civic. I think it's doing it again. Idk what's wrong with this car.

Your right I get this confused all the time

⁠​⁠@@HumbleHotshotlove the disingenuous back paddling on the INCORRECT amp lead hook up! good job! 🤦‍♂️ It WILL blow the 20A fuse on a lot of multimeters!

Fact !

Egrebal76 I beg to differ, ever tried to fix stupid?

Bullshit. This stupid multimeter doesn't work no matter what setting

DVM or DMM Digital Multi Meter.

​@@dogwalker666Digital Voltage Ohm Meter

@@wolfjay1343 That’s not a thing,

No they wont, you dont understand electricity. A fuse should have no voltage drop, a voltage drop would mean there is significant resistance across the fuse.

@@jumboegg5845 Exactly, No more than the standard volt drop for wire which over such a tiny distance is not measurable especially not with a cheap consumer multimeter used by someone who doesn't know what they are called.

I just repaired a SLK230 Mercedes with that problem. The battery would be dead after sitting a couple of days. But the alternator was intermittent. I never did isolate the power draw, but I noticed sometimes the battery went dead while running the car. I replaced the alternator when I noticed the output of the old one was low..and after that, no more draw either.

Central locking motor on VW and Audi often fails, will bleed the battery s well.

​@@georgerivera9220my car is dying out got the alternator changed he uses a old one got a new battery still dies out after a few mins how do I check for a failed engine? The engine sounds perfect?

So how do you over come that

@@melvinpervis6678that’s the answer I’m looking for as well

9 times out of 10 it will be a bum diode in the alternator so that's high on the list.

Good point! I did disconnect the control plug and it did not have affect on the draw.

😂😂😂

Any children around that could have done that? I had a nephew many years ago when he was around five, that put coins into my trucks CD player. I ultimately got them out.

A DC clamp may not read such a small current draw. The suspect drain is most likely either a bad diode in the alternator or a trunk light switch. Or if you have a light under the hood.

@Dave M it will, unless you get an absolute pos DC clamp or it is very high range luke 1000 amps. A trunk light is likely over an amp. If it is less than 10 amps, then go ahead and switch to shunting the load to measure it. If you have a short you will blow the fuse in your meter this way.

Did you connect the 2 disconnects to the pos and neg terminals or do you have two batteries and install them on both negative terminals? I need to do this temporarily until I can find the source of my parasitic drain. Thank you

@@georgew84 no I didn't have a parasitic drain

@@davidweum oh sorry. In your comment you said that you did lol

How u fix that?

@@JesusTorres-cv2fvprob changed door switch

Yep, it's not super common, but this does happen! A shorted diode in the alternator will drain the battery quickly since the two are tied directly together. This can happen if someone hooks up jumper cable or jump box backwards.

Try repairing it next time. A whole alternator rebuild is 100-200$ and it charges like a new one. 14.9-15V at idle.

When you know what you're doing it doesn't matter. Man is smarter than the display on a multimeter.

It doesn’t matter you’ll have the same number just with a negative sign in front of it

It happens ! I had another one on a Toyota camry a few weeks ago. The alternator had a bad diode after someone hooked up a jump pack backwards.

Exactly. That's what I do its unlikely that the vehicle battery is drawing more than that as that would drain it pretty quick.

And if you hit the starter while attempting to measure current, you will be lucky to blow the fuse in the multimeter. Bad luck will be to blow the ammeter from the ~300 amps that the starter can draw at inrush.

Dam everyone has a different way dam I'm looking for good advice my brain has an over load from reading everyone different ways ughhh my car dies out new battery alternator was used when replaced shady mechanic didn't tell me it was used charge me 500 now it's dying out after a new battery any advice 2011 Chevy Malibu 3.6 helpppppp

After gping to 3 different "Pros" and Over $1600.00 & 3 brand new alternators & 3 brand new batteries, I was told today that it's......You guessed it! The alternator again. The "Pros" can't find anything other that to tell me it's the alternator.

That wire is the main power supply from the alternator. The fix on this one was to replace the alternator. Thanks for watching!

That meter is cheap but it still got the job done

@@firstlast--- No, it didn't - as there is NO such thing as Zero Parasitic Draw / Load ! NEVER HAPPENED !

@@johnbishop7912 I never said there wasn't John. My point is that although slightly inaccurate the meter was still able to diagnose the draw

@@firstlast--- Slightly innacuate ? There is a HUGE difference between Zero Amps and ANYTHING ELSE !

@@johnbishop7912 5ma isn't even a blip on the radar settle down lol

Likely pulled the main charge fuse

That is 100% correct. This alternator charged perfectly at 14.2 volts with the engine running, but drained the battery overnight due to a shorted diode within the alternator. This can happen if a jump box is hooked up backwards.

@@WildFaith How interesting...thank you! My alternator 5 years old...but car only has 23k miles on it. Aren't they supposed to last waaaay longer than that?

It just depends. With electrical components, they can fail at any time with no real warning signs@@Son_of_Aragorn