Something is killing my battery ? solved ??

[herb fraser]

Even with the ignition off something is killing my battery , takes about 2 or 3 days . Not sure how to check or even what to check?
any thoughts would be great, Thanks herb
I Think its solved , well know in a few days, Thanks ,Herb

[65 Cobra Dude]

Herb,

I would put a current meter between the negative battery post and the cable. Then pull 1 fuse at a time to figure out which circuit is causing the drain. Then you troubleshoot that circuit.

Henry

[herb fraser]

Henry,this is why I come to this forum ! thanks will do Herb
when you say post do you mean the positive side of the battery ?

Herb,

I would put a current meter between the negative battery post and the cable. Then pull 1 fuse at a time to figure out which circuit is causing the drain. Then you troubleshoot that circuit.

Henry

[65 Cobra Dude]

Herb,

Typically a current meter interrupts the negative side of the battery. This means you disconnect the negative terminal and put the meter between the negative post and the negative cable you just took off. Make sense?

Henry

[Papa]

What Henry said. I'd start with the circuits that are in the "always hot" batt fed portion of the fuse panel. On my build, the brake switch wiring was reversed at the brake light switch, so power was being supplied to the brake lights all the time. Maybe check that first. I didn't realize it until I attached the bulbs. After moving to the other connections on the switch, all was good.

[RJD]

What Henry said. On my build, the brake switch wiring was reversed at the brake light switch, so power was being supplied to the brake lights all the time. I didn't realize it until I attached the bulbs.

I had the same issue with regards to the brake switch wiring, in addition to reversed wiring in a tail light harness. Sounds like a potential culprit.

[herb fraser]

Thanks guys will work on it later today

[herb fraser]

Well I went ahead and disconnected the negative side of the battery and put a meter in line. Then I pulled one fuse at a time, after I pulled all the fuses one at a time I still had the short. So I have to think that it has to be a line that has power all the time ? but wont that still have a fuse in line ? Any thought would be very helpful
Thanks Herb

[herb fraser]

I had the same issue with regards to the brake switch wiring, in addition to reversed wiring in a tail light harness. Sounds like a potential culprit.
Ok just tried that but still the same

[Just puttering]

Did the meter move any when pulling fuses? You may have one with a small drain and a fuse for clock etc. that would have a small drain, so pulling one then putting it back to pull the next will keep curent flowing through the meter although through several fuses!

[herb fraser]

Did the meter move any when pulling fuses? You may have one with a small drain and a fuse for clock etc. that would have a small drain, so pulling one then putting it back to pull the next will keep curent flowing through the meter although through several fuses!

so I am a little confused ? I guess I will have to retry it and keep a better eye on the meter . not sure how that would keep a current flowing ,can you explain a little more, thanks ,Herb

[FF33rod]

Herb
When you initially put the meter in series with the battery, what was the current that you measured?
You may know this but, from a setup viewpoint, the multimeter needs to be set for current measurement (not resistance or voltage), black lead to the chassis and red lead to the negative post of the battery (with the normal negative side of the battery cable/braid disconnected).
Steve

[Just puttering]

Herb, lets assume you have .01 amps through a fuse for the clock then .01 amps through a different fuse for a radio then .01 amps through a different fuse that is the trouble you are trying to find! Each time you pull one of those fuses, you will only remove 1/3 of the current through the meter. It will constantly show a current draw because of the other two. You need watch closely what the meter is doing or pull them all, see if you are at zero then add back and find what circuit is drawing current. Then you can trace that wire to see what it is powering.

Also, if you want, pull a fuse and replace it with the meter leads, this will check Anything going to that fuse, ahh you say the meter will not fit and touch the wires where the fuse goes, use a blown fuse and touch the contacts on the top of it. See, you knew there was a reason to keep that blown fuse!!!

[Just puttering]

Ff33rod, if i remember my high school electronics correctly, the wires should be reversed, negative to the bat??

Although, if you have a digital meter, it should read either way.

[FF33rod]

Ff33rod, if i remember my high school electronics correctly, the wires should be reversed, negative to the bat??

Although, if you have a digital meter, it should read either way.

Correct on the digital meter.
For analog - Negative to the battery if you're working on the positive side since we're talking about the negative side it's the other way around...

[herb fraser]

Thanks guys ! LOTS to do today to try this, will keep you posted and again thanks for the help, Herb

[wallace18]

Herb an old school method is disconnect the negative cable and install a 12 volt bulb test light inline to the - post of the battery and the cable you removed. If you have a draw the light will glow or light up. Pull fuses till the light goes out. That is the drain source. We used this before digital stuff and it works 98% of the time.

[herb fraser]

Tom old school is best and easy ! Thanks I will give it a go !


Herb an old school method is disconnect the negative cable and install a 12 volt bulb test light inline to the - post of the battery and the cable you removed. If you have a draw the light will glow or light up. Pull fuses till the light goes out. That is the drain source. We used this before digital stuff and it works 98% of the time.

[rponfick]

Herb, do you have the electric power steering. In testing mine today I discovered it works with the key turned off. Is that normal. I do have the red power wire run directly back to the battery, as instructed in the manual..
Could the power steering have some current draw with key off?
Good luck.
Ralph