How to Find a Short in your Car

today we're gonna be diagnosing a short or a potential short the car will not start after a few days so it could be a few things it could be an alternator that's going bad it could be a short or it could be a bad battery this video is going to show you how to test to see where if you have a short and where your short is so we're gonna pop the hood get to the battery first thing you're gonna do is get to the battery and on these PT Cruisers you this is right below the air filter so there's these two tabs on the side and that one there you just pop them open and then you can lift this and your battery is right there I'm also gonna take off this so you just use a flathead screwdriver and unscrew this and then this whole piece will come off with our air filter box off we have access to the battery and so the positive is here the negative is here what we're gonna do is this is a 10 millimeter wrench fits on here perfect we're gonna loosen the negative side now you could either loosen the negative or the positive I prefer the negative because if when you're doing this test if you ground out the negative you're grounding out a ground it's not a big deal if your ground out the positive your grounding out where the power is coming from so that could create a short and blow something so we take off our negative before we start testing the connections we want to make sure that we sand we'll get a little bit of sandpaper I'm gonna send the terminal the post and the lead and you're gonna get inside here I can't really do it with one hand but you get the idea so sand inside here so it's nice and sanded and there's a really good connection and then you don't want these two touching so keep them separated and you don't want this touching your ground either we have this multimeter and what it does is it gives you DC volt it gives you your ohms which is continuity AC volts DC amps and a battery test for a load we're going to want to test the battery first to make sure it's good so make sure your connections on the right one see it's this battery grounds there and when we use 20 volts as our base so now let's test the battery very simple you just touch it to two sides negative to negative positive awesome this is twelve point four it should be twelve point six or higher so that's good I've been messing around with the battery a little bit so it's it's down a little bit and there's obviously a problem so it's it's down a little bit but that's charged enough where we could do this test so now what we're gonna do is go to our amps DC amps and if we do that we have to put it to the DC amp side which on most multimeters you need to move this so now it's on amps now we're going to take our disconnected negative terminal and bridge the gap with these so we're just connecting and you could see right away that says seven point eight six almost eight eight amp load so now what we're gonna do is come over to the fuse box and we're going to start disconnecting fuses one by one so here's your fuse box on a PT Cruiser some cars it's over here some cars it's it's underneath the steering wheel somewhere some cars it's over here but on the passenger side like it's like that on a Corvette now what you're gonna do is gonna disconnect the fuse they're our fuse pullers which make this easy I just use a little needlenose and you just pull it straight out now your fuse is disconnected that's one fuse you can look in your manual or in this case it's on here what each fuse does so that fuse was a 25 amp HD lamp switch so a headlight lamp switch and and that's the right one that's in position one so if there's a problem with our headlight lamps and that's causing the short you would notice that there would be a drop in voltage here will check and nope still there's still a parasitic draw of close to 10 amps it's 9 9 amps and so we're gonna just pull fuse by fuse until we see that drop down to as close to zero as possible and it should be in the decimal places and once that goes down to zero that means we found the correct fuse that's connected to something could be a radio could be a headlight could be and whatever the fuses are connected to and then we could diagnose that and that's where our short is and just as a reminder one thing you want to make sure is there's parasitic draw all the time especially like when your doors open your dome lights and stuff are on when your glovebox is open that light is on sometimes depending on your hood if your hood has a light this one doesn't but if your hood has a light and your hoods up that's on so you want to just connect the light on the hood you want to close all your doors and then you want to check your parasitic load of 9 amps in this and when you're pulling the fuses you want to try to keep the door closed so a good thing is you could pull the fuses with the door with the window open and the door closed the other thing to remind you is that most cars have a fuse box underneath or in the engine compartment which is right here and the label fuses and what they do and what they're for is right here if you can't find the problem with those fuses inside the cabin you could check these fuses I'm gonna pull fuses one by one and have somebody tell me if this changes as I pull nothing nothing nothing nothing change went down to 1.59 a fuse number eight which I will show you there's still a decent amount of draw but we'll figure that out later but the big thing is fuse number eight which is for the fog lights ends up being the one that caused a huge draw so that's what we're gonna look up next and see if we could find why it's causing the draw I put the fog light fuse back in plus the fog lights should be off everything's in the off position sure I went back up and notice the fog lights are on so there's your draw sometimes it's not that easy in my pickup truck it was the radio that was broken and everything worked fine the battery would just die after two days of sittings so the problem is this fog light now that you have the problem area figured out you could go and diagnose the fog lights or your radio or whatever your problem ends up being but that's how you test for a parasitic draw hopefully this video has helped you guys and if you have any comments or tips or any ideas a lot of times you guys give me good ideas for stuff that I didn't include and I add them in the annotations that would be awesome I cover what I think is important and what I could think of as I'm doing stuff to fix my own vehicles so if you could add stuff that would be very helpful so comment like the video if it helped and subscribe if you wanna see some more how-to videos I'll be doing some more very soon

Channel: ChrisFix

Views: 2,706,941

Rating: 4.8846107 out of 5

Keywords: how to find a short, how to diagnose a short, how to see if you have a short, short, parasitic draw, draw, parasitic, diagnose a short, find a short, shorted, battery, alternator, battery dying, battery drainage, multimeter, draining battery, How To Perform a Parasitic Draw Test, short in car, car dies overnight, car wont start, no power in car, How to find a short in your car, shorted car, battery going dead overnight, parasitic draw test, testing parasitic draw

Id: n5FJDgcdii8

Length: 8min 42sec (522 seconds)

Published: Sat May 11 2013