Parasitic battery drain!

[firewalk]

So I’ve been having this parasitic battery drain for some time now. I’m geting tired (and broke) of replacing batteries all the time. When ever I install a brand new and fully charged battery, it will be flat after 5-6 days at most.

So I bought a “prioritystart battery protector” which goes between the battery and the positive cable. Whenever the battery goes bellow 11,7 volts for more than 1 minutte it will disconnect power totally, thus ensuring that there is always enough power to start the car.

This actually works. However, My batteries still keep dying! My battery which was brand new 2 months ago now won’t hold a charge. It will start the car, but a few hours after parking the car it will read only 11,87 volts.

So the question is:

1: Will a battery die from geting drained down to 11,7 volts? I know they will die from geting flat. But 11,7 is far from flat?..

I know that in order to search for the problem you are supposed to set up the multimeter between the negative terminal on the battery and the negative cable, measuring amps. Then you remove the fuses one by one. I’ve don this. The only problem is that in my case it seems like EVERY darn thing is phulling amps to some degree! Even hours after parking the car.

I will typically phull one fuse, and it will decrease the load by a few miliamps.. Then I phull another one and it goes down by a few more miliamps. Seems like I have to phull nearly every darn fuse to get it to go down to aceptable levels. So as you can imagine, problemsolving this isn’t easy :unsure: Nor can I just replace the entire wiring. And I can’t drive around with no fuses, as nothing would work!

Any Ideas? I was hoping the prioritystart would get me around the problem. Could it just be a bad battery from the dealer? Or are they simply not designed to widhstand beeing drained down to 11,7 volts, then started and charged up to 12,6 again.. ?

I need some advice! This is eating at me.. ::(

Topic

[college man]

First whats the year,make,model and engine size are we
having the problem with? If you do have a electric vampire
stealing your power.Then we need to find it.first we need to
know some things.battery terminals clean and tight.cables in
good condition. battery and charging system working correct.
battery and charging system should be load tested.Here is some
videos which will help aid you in diagnostic.11.7 v is low to try
and start and run the car.Thats is the battery surface charge.we want
12.6v

[ytram]

I would start first by checking fuses with ignition switch off. If the fuses have the spots you can put the probes from a multimeter,(you are measuring the fuse in series with its self) measure between these 2 spots. If current is going through, there should be a millivolt reading. Higher the mv is the more current.

[ytram]

I would start first by checking fuses with ignition switch off. If the fuses have the spots you can put the probes from a multimeter,(you are measuring the fuse in series with its self) measure between these 2 spots. If current is going through, there should be a millivolt reading. Higher the mv is the more current.

[twiggy]

As college man suggested, I vote for your charging system as being the issue here. If you have a DMM, measure the voltage on your battery terminals while your car is running per the videos posted above. Let us know what you measure.

[twiggy]

As college man suggested, I vote for your charging system as being the issue here. If you have a DMM, measure the voltage on your battery terminals while your car is running per the videos posted above. Let us know what you measure.

[EricTheCarGuy]

[quote=”college man” post=32226]First whats the year,make,model and engine size are we
having the problem with? If you do have a electric vampire
stealing your power.Then we need to find it.first we need to
know some things.battery terminals clean and tight.cables in
good condition. battery and charging system working correct.
battery and charging system should be load tested.Here is some
videos which will help aid you in diagnostic.11.7 v is low to try
and start and run the car.Thats is the battery surface charge.we want
12.6v

Wow, this covers just about all of it. This should get you started anyway.

[EricTheCarGuy]

[quote=”college man” post=32226]First whats the year,make,model and engine size are we
having the problem with? If you do have a electric vampire
stealing your power.Then we need to find it.first we need to
know some things.battery terminals clean and tight.cables in
good condition. battery and charging system working correct.
battery and charging system should be load tested.Here is some
videos which will help aid you in diagnostic.11.7 v is low to try
and start and run the car.Thats is the battery surface charge.we want
12.6v

Wow, this covers just about all of it. This should get you started anyway.

[firewalk]

Thanks guys, great videoes! Watched them all.

It’s an MR2 MK2 3S-GTE.

I’ve been able to rule out the alternator. It’s fine, I replaced it a few months ago due to defective voltage regulator.

Doing the amperage test, I’ve been able to fix everything EXEPT two sircuits which I can’t for the love of GOD figure out how to fix.

The two fuses in question is:

1. DOME
2. HAZ – Horn

Nr1 involves, as the name suggest: the dome light, light in the doors and power locks.

nr2 involves the Horn and the hazzard lights.

So what did I do?

Well, I teared down half the interiour and the dash, and unpluged all the conectors going to the doors, I took down the dome light and removed the connector going to that. Made sure nothing was pluged in and nothing worked.

Still, the amperage draw remains exactly the same! No change…

Seems theese two fuses dras about 160 miliamps together. About 80 miliamps each.

How should I procead? I’m stuck..

[firewalk]

Thanks guys, great videoes! Watched them all.

It’s an MR2 MK2 3S-GTE.

I’ve been able to rule out the alternator. It’s fine, I replaced it a few months ago due to defective voltage regulator.

Doing the amperage test, I’ve been able to fix everything EXEPT two sircuits which I can’t for the love of GOD figure out how to fix.

The two fuses in question is:

1. DOME
2. HAZ – Horn

Nr1 involves, as the name suggest: the dome light, light in the doors and power locks.

nr2 involves the Horn and the hazzard lights.

So what did I do?

Well, I teared down half the interiour and the dash, and unpluged all the conectors going to the doors, I took down the dome light and removed the connector going to that. Made sure nothing was pluged in and nothing worked.

Still, the amperage draw remains exactly the same! No change…

Seems theese two fuses dras about 160 miliamps together. About 80 miliamps each.

How should I procead? I’m stuck..

[college man]

If the dome light is not on.Then its not drawing power.rule out
If the horn is not blowing no draw rule out.
if the hazards are not on rule out.
If the horn and dome fuses are pulled.does the draw
go away.Did you pull every fuse for the test?unless one
of your computers is not going to sleep.

[college man]

If the dome light is not on.Then its not drawing power.rule out
If the horn is not blowing no draw rule out.
if the hazards are not on rule out.
If the horn and dome fuses are pulled.does the draw
go away.Did you pull every fuse for the test?unless one
of your computers is not going to sleep.

[firewalk]

I phulled all the fuses. Eventually I figured out that DOME and HAZ HORN was causing the drain. I then installed all fuses again, exept the DOME and HAZ horn. When doing this my multimeter showed a constant draw of about 10 miliamps (0,010 amps) which is well bellow the 50 miliamp limit. I assume this 10 miliamp drain is due to clock, computer memmory etc.

What I did next, now that I know that the drain was gone, was to reconnect the negative battery cable and use my multimeter to measure trough the pins in each of the fuses in question, DOME and HAZ HORN.

I started with the DOME circuit. With the multimeter hooked up, Power will flow trough the multimeter, just as if the fuse were still in place. But I can now measure hoe much juice is actually going trough in real time.

I then started to disconnect stuff. Like the dome light itself, the doorloom connectors etc. But as I said, Nothing made a difference.

I repeated this process witht he HAZ HORN fuse, and I couldn’t find any problems there either..

Example:
If you have a battery, with wires going to a glowing bulb. That will draw power for sure. But if you remove the bulb, no power should be drawn right?..

That’s my logic in this. But I’ve removed everything I can think of, and still the drain is just the same.

Could there be some sort of short somewhere causing this tiny drain? I find it kind of weird that I have two seperate drains on two seperate circuits/fuses and they both reads nearly exactly the same! 80 miliamps.
I would think that a short, even a tiny one would produse way more drain than that. But then again my experience with electrics is limited.

For now I’ve just removed theese two fuses. That stoped the drain. However, I have no Horn, no power locks, No alarm and no lights inside the car..

I have no Idea where or how to search for this drain ghost.. ??

[firewalk]

I phulled all the fuses. Eventually I figured out that DOME and HAZ HORN was causing the drain. I then installed all fuses again, exept the DOME and HAZ horn. When doing this my multimeter showed a constant draw of about 10 miliamps (0,010 amps) which is well bellow the 50 miliamp limit. I assume this 10 miliamp drain is due to clock, computer memmory etc.

What I did next, now that I know that the drain was gone, was to reconnect the negative battery cable and use my multimeter to measure trough the pins in each of the fuses in question, DOME and HAZ HORN.

I started with the DOME circuit. With the multimeter hooked up, Power will flow trough the multimeter, just as if the fuse were still in place. But I can now measure hoe much juice is actually going trough in real time.

I then started to disconnect stuff. Like the dome light itself, the doorloom connectors etc. But as I said, Nothing made a difference.

I repeated this process witht he HAZ HORN fuse, and I couldn’t find any problems there either..

Example:
If you have a battery, with wires going to a glowing bulb. That will draw power for sure. But if you remove the bulb, no power should be drawn right?..

That’s my logic in this. But I’ve removed everything I can think of, and still the drain is just the same.

Could there be some sort of short somewhere causing this tiny drain? I find it kind of weird that I have two seperate drains on two seperate circuits/fuses and they both reads nearly exactly the same! 80 miliamps.
I would think that a short, even a tiny one would produse way more drain than that. But then again my experience with electrics is limited.

For now I’ve just removed theese two fuses. That stoped the drain. However, I have no Horn, no power locks, No alarm and no lights inside the car..

I have no Idea where or how to search for this drain ghost.. ??

[college man]

well wait a minute. Alarm can you just unplug the alarm?
then retry the test.;)here is a link for a wiring diagram.
Btw what year was the car?
http://www.bbbind.com/tech_database.html

[college man]

well wait a minute. Alarm can you just unplug the alarm?
then retry the test.;)here is a link for a wiring diagram.
Btw what year was the car?
http://www.bbbind.com/tech_database.html

[Author]

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