Power being drawn from my battery

So I keep having a dead battery. I have narrowed it down to the engine fuse box. If I leave the fuse box power wire connected and attach the negative I get an arc. When that happens I also hear a click in the front corner behind the head light. I am guessing that is my power draw. Anyone know what this clicking might be? Any help would be great.

 

There is parasitic draw to keep the electronics operative (e.g. allow your remote to unlock the door, keep some information in the computer memory, etc.)
A weak battery would draw down especially if it has failed internally. If the battery is good, have to put an amp meter on the cables to determine what draw is too much. An arc when connecting the battery wouldn't necessarily be a problem indicator.

 

It's a decent arc but I will try attaching it and see how much draw it has.

 

The fuse box in the engine compartment always has power.

 

Start with a load test of the battery.

 

After you check the battery ,

http://www.youtube.com/watch?v=KF1gijj03_0

 

...And check the charging system at Autozone, for free.

 

I have to disagree with the video on one specific step. He removed the ground completely, then connects his meter in between the negative post, then the cable. I have found that in many cases that you can do one of two things this way:
1. If you have an intermittent draw of a relay or a module that sticks upon occasion, when you disconnect the terminal you can clear that problem, and when testing it won't show up. You have replaced the battery, and tested the system, and it passed, so you return the vehicle to the customer and the next day, battery is dead, and you have a pissed off customer.

2. We all know that when you connect the battery you get a spark. That spark CAN exceed the amp measuring capacity of the meter, and blow the fuse. Those fuses are NOT cheap.

The BEST way to check for an amp draw is to use a tool like this:



You install this tool, which can be bought at WalMart for less than $10 usually. Install it on your vehicle. Then you go drive the vehicle. Take it down the road where the vehicle's computers and relays are operated normally. Then you bring it back into the shop and connect your multimeter with one lead on the clamp, and the other lead on the post of the tool. Set the meter to the correct scale. Then you slowly loosten the green knob. This allows the current to then go through the meter, but does not at ANY point directly interrupt the current flow, since you never at any point fully disconnect the battery.

With today's computer systems you can get all sorts of modules and other devices that will create a parasitic draw, but if you interrupt the power and reconnect it again, the draw may not be there. Other than that the video is pretty good and detailed.

 

Good job bill!!

Haven't seen you in the houston bs in a while. Maybe since the girls left lol

 

Hey bro. Nah, I just can't keep up with you guys. You post like 40 times in an hour. lmao.

Wasn't because the girls left. I have just been busy as hell. I may pop in to say hi shortly.

 

Lol i don't have anything to do when it's slow at the shop
So i post whore for a bit

 

Thanks for the correction Bill .
Considering I used a light bulb to test Parasidic loads back in the day , I thought the video was an easy way to get out of typing lol
I didnt even notice that ...awesome catch !!!

 

I remember the days of the lightbulbs. If you thought it was a small drain, use a 194 peanut bulb!

 

Great point there Bill, I test for a draw the same general way without the disconnect terminal, but that makes it much easier.

Keep in mine many ECMs take a bit to "go to sleep" when draw testing, and since I didn't watch the video, I'm assuming it suggests pulling fuses to locate the circuit causing the draw. Also, up to about 500mA (half an amp) draw is pretty normal with modern vehicles.

And yup, I've done the dim vs bright "test light draw test" its pretty quick and easy, though somewhat less accurate.

 

ive heard that the "normal" parasitic draw should be 100ma max. (that's 1/10 of an amp.) if its more then it will drain the battery faster the more load is on it.

also you said you herd a click by the headlight? back in my Honda civic days i had a friend with similar problem and click. turned out to be his a/c clutch was stuck on due to a shorted out relay.

 

Start pulling fuses till your "arc" goes away assuming it's fairly large.

 

That can leave you chasing computers.

 

Diemaster is closest. A properly "sleeping" car or truck should be drawing less than 50mA of current. if you had 500mA of a draw constantly you would kill a battery within 2 days if the vehicle was not started.