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I've got negative disconnected, a wire on battery term ground and another wire on negative battery cable going to a multimeter set on 10amps. I cant get the car to power up showing amps then going to sleep. It just stays at 0 amps when I connect everything up. Battery is new, has 12.6 volts with car off, been sitting in engine bay unhooked for a few days till I could do this test.
If it is always showing 0 your DVOM may be bad...what does it read when you open the door and your interior lights come on ??...in the picture it is showing 2 milliamps...pulling fuses to find a draw is NOT the best way to do a parasitic draw test !!
If it is always showing 0 your DVOM may be bad...what does it read when you open the door and your interior lights come on ??...in the picture it is showing 2 milliamps...pulling fuses to find a draw is NOT the best way to do a parasitic draw test !!
when I connect the mm it doesn't even turn the car on. I was looking at my fuses in mm but they're ceramic so I don't know if they're bad. It reads voltage and resistance though.
If I have it hooked up in series, the car doesnt turn on. I mean no interior or dash lights nothing. I was reading it should "wake" the car up once the connection is made.
My mm has 2 fuses, .5 amp/600v and a 10a/600v. They're ceramic so I'll have to take them to a friends house to test them with his meter or gamble and buy new ones. Pretty ironic I have the tool to test them but cant.
Sounds like a fuse is shot if the interior lights didn’t come on...my Vantage Pro uses an automotive fuse...easy to replace !!
ya I'm wondering if the big fuse is for amps and its blown. I've never used it on amps in the 10+yrs I've owned it so maybe it's bad. The fuses for it that I can find on Amazon are 10bucks for 2 of the same size.
Didnt think of it before, I just took out the big fuse and left the small fuse in mm and it still reads resistance. The other big fuse reads OFL so maybe it looks like that fuse is my problem.
If you set up your meter THEN turned the ignition, it is no wonder you blew the fuse in the meter, and the meter may have been fatally wounded too. When you turn the key on several essential circuits draw current, the fuel pump in particular. You should see 40 amps or more momentarily when you turn the key ON.
So if your meter still works, remove the meter from being series in the circuit, and put your battery cable back on. Now, you need to have an idea of the suspect circuit that is retaining power when it should not be. Then find the associated fuse for that circuit. If you look at the top of the fuse you will see two little exposed spots of metal. First, set your meter and leads for reading 12VDC. Put the black meter lead on a ground or the battery neg and touch both little spots on the fuse. If you get 12V on both spots, GREAT!! that tells you two things 1. there is voltage to the circuit, and 2. the fuse is good.
Now, go to this website: https://www.powerprobe.com/fuse-voltage-drop-charts These charts show you the voltage drop across a given amp-rating fuse as a function of current through the fuse. So, just like the picture shows you put one of your two meter probes on one of the bare fuse spots and the other probe on the other spot. The millivolt reading you see on the meter reflects the current through the fuse (and therefore, the current being consumed BY the devices on the circuit}. If that voltage goes to zero when you turn the key OFF,then the system turned that circuit off. So your test is to measure millivolts on a fuse shortly after you turn the key OFF, then come back later to any fuses that showed there is current. If there was no change in millivolt reading on that fuse, then there is your bogey.
Fuses are basically resistors, and like any good resistor, they heat up when current flows through them. When the circuit current exceeds the ability of the fuse to pass it, the link melts and the fuse opens.
If you set up your meter THEN turned the ignition, it is no wonder you blew the fuse in the meter, and the meter may have been fatally wounded too. When you turn the key on several essential circuits draw current, the fuel pump in particular. You should see 40 amps or more momentarily when you turn the key ON.
So if your meter still works, remove the meter from being series in the circuit, and put your battery cable back on. Now, you need to have an idea of the suspect circuit that is retaining power when it should not be. Then find the associated fuse for that circuit. If you look at the top of the fuse you will see two little exposed spots of metal. First, set your meter and leads for reading 12VDC. Put the black meter lead on a ground or the battery neg and touch both little spots on the fuse. If you get 12V on both spots, GREAT!! that tells you two things 1. there is voltage to the circuit, and 2. the fuse is good.
Now, go to this website: https://www.powerprobe.com/fuse-voltage-drop-charts These charts show you the voltage drop across a given amp-rating fuse as a function of current through the fuse. So, just like the picture shows you put one of your two meter probes on one of the bare fuse spots and the other probe on the other spot. The millivolt reading you see on the meter reflects the current through the fuse (and therefore, the current being consumed BY the devices on the circuit}. If that voltage goes to zero when you turn the key OFF,then the system turned that circuit off. So your test is to measure millivolts on a fuse shortly after you turn the key OFF, then come back later to any fuses that showed there is current. If there was no change in millivolt reading on that fuse, then there is your bogey.
Fuses are basically resistors, and like any good resistor, they heat up when current flows through them. When the circuit current exceeds the ability of the fuse to pass it, the link melts and the fuse opens.
Well i had not originally turned the key. The very first thing I did was hook up the wires from the battery to meter. I didnt even have my keys with me in the garage. It was only out of curiosity later that I got my keys. Now I know so thanks.
Even when I did turn the key nothing in the car turned on. It was like I had the battery unhooked.
No, car starts, runs, drives fine. When I originally hooked up my meter, the car wasnt on, nothing was on, the keys were inside. Meter wasnt reading anything but 0 hooked up in series. I now think the fuse was blown the whole time even before I started working on it today. I ordered a new fuse.
I'll try again in a few days to see if I can get it to work. I've got a battery drain I'm going to find it so I can enjoy my car again. Been leaving it at home so I dont get stranded.
measuring voltage across a fuse is a safe way to find a circuit that is the drain cause. Putting a meter directly in the path is tricky, because you always have to be sure the current actually being measured is less than the rating of the meter. measuring voltage drop, or using a clamp on type meter is safe for the meter. Clamp-ons are more expensive.
Ok well strangest thing, got my new fuse and mm works. Hooked it up and everything powered down, amps went to .011. Noticed I didnt have my new dual Aeroforce gauges plugged in so i decided I needed another test. Hooked up the 2 gauges and the fuel pressure sensor add on to one of the gauges. Closed the door, hooked up mm and my ac unit stayed on. Well it wasnt doing that 5min ago. Unplugged the fuel pressure sensor on the back of gauge and it went off. So something is up with that pressure sensor. I dont know yet, I've used it for years on the single gauge I had no problem. I just added a 2nd gauge and now this is happening. It's a 5v source and ground I believe. I'm certain i tapped into map sensor. Anyways, i think i found my problem, I'll update later.
Edit: It was pulling .2 amps when the climate control was staying on.....
Battery drain test, what am I doing wrong?
