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What should a Battery Sit at Hooked up with an Alarm overnight

I just bought a Brand New Optima Red Top 800CCA-1000C

I drove the car all around yesterday, Since 3:00PM Yesterday I have been going out every 30 Minutes and Reading it.

When I went to bed at 11:30 it was sitting at 12.73V

I just went out today and its at 12.55V a Perfect battery sits at 12.6 Right

Is it normal to Drop one Full Volt with an Alarm Hooked up and Not Armed

I have a Big Current Draw and I'm trying to find it

That’s why I went and bought a Brand new Optima Battery to Start New

When the Car Runs the Battery Reads 15.01V and then only drops to 14.99v

When I turn the car off it reads 13.05 and Seems to Drop from there I guess trying to get to the 12.6V mark

The Coils in the Alt look Burned and Black now and I hear a weird Noise

Could the Regulator Be Bad and while Charging the Battery to 15.01 Volts Be Draining the Battery when Its turned off.

I even Replaced all the Fuses in the Alarm system in the Fall to Lower Amps and still the same thing.

I'm Getting Midas on Monday to do a Charging Test for $23.99 but don't want them to love up my alarm if they put there tester on.

I would really like some Expert Help on this:)

!2.55 is aceptable after about 10 hours at rest, 15.01 most certainly isn't, your voltage regulator has blown. some of your smaller bulbs should have burned out by now.

howie ll wrote:

!2.55 is aceptable after about 10 hours at rest, 15.01 most certainly isn't, your voltage regulator has blown. some of your smaller bulbs should have burned out by now.

Do you mean at my Cluster??? inside the car

Take your readings at the battery, A) It's more accurate and B) You'll lose about .25V between battery poss and where you were doing it. Turn everything off, keys out of car shut doors, wait 2 mins and with hood open, disconnect battery neg, then set up your DMM to the 10amp (or 20 if it has it), position and the probes accordingly, take your neg to the terminal and the pos to the disconnected battery wire. If the alarm is disconnected (fuses out) the average reading should be between 40-70milliamps. Anything approaching 1 amp except on a late Jaguar, BM, Mercedes, Caddy or car of that ilk means something is draining though I still suspect the voltage regulator.

howie ll wrote:

Take your readings at the battery, A) It's more accurate and B) You'll lose about .25V between battery poss and where you were doing it. Turn everything off, keys out of car shut doors, wait 2 mins and with hood open, disconnect battery neg, then set up your DMM to the 10amp (or 20 if it has it), position and the probes accordingly, take your neg to the terminal and the pos to the disconnected battery wire. If the alarm is disconnected (fuses out) the average reading should be between 40-70milliamps. Anything approaching 1 amp except on a late Jaguar, BM, Mercedes, Caddy or car of that ilk means something is draining though I still suspect the voltage regulator.

Thanks posted_image

Car is a Cavalier 2.4L

I hope to try this on Sunday if it doesn't rain

What Number should I have if I don't pull the Alarm Fuses 1 amp about(I will be doing both ways With Fuses installed and not installed)

About it might being the Alternator Regulator even through the car is Turned off it still can Drain from the Alternator

I always thought the Battery was like a big capacitor and Filters the Ripple AC from the Alternator. I didn't know the Regulator Could Back Feed and take volts from the Battery and kill it.

Look to about 70miliamps with alarm connected. If set to 10amp range will show as 0.07, no if voltage reg is too high it will cook the battery, bend a vertical plate inside and the battery will fail to take a charge, otherwise your description is correct. Except a cap stores it as current, a battery stores electricity chemically.

What brand of digital meter are you using?

Capacitors store energy chemically, as well.

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Ideal - cmon dude, add to topics in a useful manner, not stuff that is obvious.
Story - Phzzzt! Hey, what happened?! ... Isn't it obvious?
Moral - Never dismiss the obvious.

i am an idiot wrote:

What brand of digital meter are you using?

I had a Fluke but was Stolen

So I bought a Cheap DMM that looks like this it's 10AMP MAX

posted_image

Chances are you have a slightly inaccurate meter.

Well I first put it on the 20V Scale and Got(0) LOL

Then Finding the 10AMP Scale I got 0.19 With the Alarm Fuses Still Hooked up

The Battery Was sitting at 12.33V This Morning

When I put the DMM back on the Battery with-out the (-) Terminal On it reads 12.23V Very Wierd Indeed posted_image

I did see a Spark

As I forgot the (+) Probe was in the 10AMP Slot and then put it at 20V Scale and saw the spark when I went to read the battery the normal way

I hope I didn't short anything out on this battery or Alarm now posted_image

I'm going to pull the Fuses Right now

Just wanted to give a update

Update

I just got almost the same reading

0.19

I just need to find out if those are the main 20AMP Fuses(Well 15AMP) that I pulled

But 0.19 seems very Low from what I was told

Also the Battery did jump back up to 12.57V After I typed my last response

posted_image

howie ll

Where Did you go???

Actually 0.19 is too high! You should have seen about 0.040. 0.19 is 190milliamps, much too high for that vehicle with everything shut down.

Yeah, the 0.19A is way too high. What is the reading with the fuses from the alarm pulled out?

Also, lowering the size of the fuse won't reduce the current. Fuses are over current proection devices, NOT current limiting devices.

Well, I guess, technically they are also current limiting devices, but they only have a one time use in that fashion!

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Kevin Pierson

howie ll wrote:

Actually 0.19 is too high! You should have seen about 0.040. 0.19 is 190milliamps, much too high for that vehicle with everything shut down.

That was with the 10AMP Setting Like I show in the Picture

Was that the Right Setting???

So I need to take the car in A.S.A.P if I did everything right then,Should I pull the Fuses before I take to get tested

So you still don't think its the Alternator Then with a reading like that,The Alarm is Toast I guess now Even though everything works

It's a Autopage RS-855 (2005) Model Year

I Do have a Picture of what the alternator looks like

I'm going to Unlplug the main plugs that go into the steering wheel and then take that reading again

Then I would know If its the Alarm Right???

Leave all fuses in-place.
Take your reading from the battery.
Remove fuses from suspected circuit.
Take your reading from the battery.

If the reading changes considerably, then you have found the suspected circuit. If not,

Remove all fuses from the interior fuses box. Taking care to note each fuse location and size.
Take your reading from the battery.

If the reading changes considerably, then you must replace each fuse individually and take a reading from the battery, with each. Post back when you have some more information.

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Ideal - cmon dude, add to topics in a useful manner, not stuff that is obvious.
Story - Phzzzt! Hey, what happened?! ... Isn't it obvious?
Moral - Never dismiss the obvious.

Yes you had it correct in the picture. In addition to what the eminent and knowledgeable gentlemen wrote in their last post, do not under any circumstances disconnect alternator whilst running engine. The only acceptable method is engine off, disconnect one fuse at a time, both factory and aftermarket

loneranger wrote:

Leave all fuses in-place.
Take your reading from the battery.
Remove fuses from suspected circuit.
Take your reading from the battery.
If the reading changes considerably, then you have found the suspected circuit. If not,
Remove all fuses from the interior fuses box. Taking care to note each fuse location and size.
Take your reading from the battery.
If the reading changes considerably, then you must replace each fuse individually and take a reading from the battery, with each. Post back when you have some more information.

Do you mean to just Messure the Battery the Normal Way or doing that Test like I was doing before Well pulling the Fuses. posted_image

If I do unplug the main plug that goes into the steering Wheel and then complete the Circuit With the (-) Battery Terminal and DMM like before,Will my Passlock 2 Lock up after I re-hook everything up and try and start the car.

Do those tests at the battery, why would you need to unplug main lead at steering wheel?

i have seen alternators amretures stay magnitized take a small screw driver or somthing like that put it on the bolt for the pulley if it sticks then i would change your alt if they stay magnetized it will kill your batt also 15 volts is too high your can take your paracidic draw test then unplug the alt and see if it goes away

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If i Can't Install it I Don't need it Joe

As Far As midas is concerd there's nothing wrong with my Electrical System

I will scan the sheet in today with the results

{Quote from Owner} You have a High Powered Radio(Not even Hooked up)-(Owner I don't Care) and an Alarm that someone at sometime was monkeying around under my Dash to install the Alarm.

He Said 15V that’s Fine but if I start getting up to the 15.05V Range There's a Problem, Its a 12V Battery you Know posted_image

Didn't have a answer When I told him it Dropped almost 1+ Full Volt from the Night before to taking it to him

I'm Waiting to Hear Back from Auto page so I can send my Alarm Brain in so they can test it out

I still will Do that Screw Driver Test and Start to Pull Fuses, But I think the Main Power Leads for the Alarm are Gone Because I did pull the Fuses and that 0.19 Number stayed the same and also still have Current running in those wires with-out a Fuse Hooked up even.

The Reason I was going to Unplug the Main plug from the Steering wheel was I wanted to See if the Main Power leads for the Alarm are still Good and Soldered Tight.

Also I have 3 Fuse Holders Hooked up to the Main 10 Gauge Power Lead for my Trunk Release and my Door Locks

It's 2 10 Gauge Wires that Go into 1 Main 10 Gauge Wire and then everything is Hooked up

Here's the Results

posted_image

I thought you said the car was resting at 15vdc? 14.4 is quite a huge difference.

Also, you do realize that a "charging system test" won't actually test what you are looking for.

You have already proved you have an excessive current draw - you need to focus on figuring out what the draw is and eliminating it.

The only way you are going to do this is by hooking the meter back up in series with the battery and then start unplugging things until the draw goes away. If it starts around .19A I wouldn't stop unpluggin / pulling fuses until it drops below .05. In reality I would expect it to be closer to .03, but nowhere above .05a.

I, personally, would start at the alarm - I would unplug the entire brain - every connector and remove it. I would also unplug / disable any alarm related module (aftermarket) and relay. If that doesn't make a difference start pulling fuses, one by one and check the reading after each fuse. If that still doesn't fix the issue start unhooking the alternator and see if that causes the current to drop.

A little background would be nice, too. When did this start happening? Was it right after the alarm was installed? Was it right after any other electrical mod was made?

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Kevin Pierson

KPierson wrote:

I thought you said the car was resting at 15vdc? 14.4 is quite a huge difference.
Also, you do realize that a "charging system test" won't actually test what you are looking for.
You have already proved you have an excessive current draw - you need to focus on figuring out what the draw is and eliminating it.
The only way you are going to do this is by hooking the meter back up in series with the battery and then start unplugging things until the draw goes away. If it starts around .19A I wouldn't stop unpluggin / pulling fuses until it drops below .05. In reality I would expect it to be closer to .03, but nowhere above .05a.
I, personally, would start at the alarm - I would unplug the entire brain - every connector and remove it. I would also unplug / disable any alarm related module (aftermarket) and relay. If that doesn't make a difference start pulling fuses, one by one and check the reading after each fuse. If that still doesn't fix the issue start unhooking the alternator and see if that causes the current to drop.
A little background would be nice, too. When did this start happening? Was it right after the alarm was installed? Was it right after any other electrical mod was made?

The Battery Reads 15V when running, Rested goes around 12.55V But I haven't checked in 1 Day or so

I thought that Test Means my Alterntor is Fine and the Regulator is fine

What Else Could it really be if everything Checks out and I take everthing apart and unhooked and still get 0.19

Quick Question,Will I Pop my Fuseable link for my alt if I unhook it and then do the test

Just need to know so I can pick some things up tommrow its my only car for now

I started seeing things after the Alarm was installed,But nothing like in the last 6 months with it needing a Boost everytime I went to start it

I will let everybody know what I find in the Morning,Again thank you for all the replys posted_image

I absolutely agree with what Kevin said about the test it tells us nothing about any current draws in the system, it's simply a test for the battery. Also I agree about their voltage readings differing from yours. Do exactly what Kevin suggests, that's what I'd have done originally. That reading makes me think a relay might be staying latched on, or an amp or something such as an aftermarket accessory not switched off. Faulty glovebox light anyone?

black cavy wrote:

The Battery Reads 15V when running, Rested goes around 12.55V But I haven't checked in 1 Day or so
I thought that Test Means my Alterntor is Fine and the Regulator is fine
What Else Could it really be if everything Checks out and I take everthing apart and unhooked and still get 0.19
Quick Question,Will I Pop my Fuseable link for my alt if I unhook it and then do the test
Just need to know so I can pick some things up tommrow its my only car for now
I started seeing things after the Alarm was installed,But nothing like in the last 6 months with it needing a Boost everytime I went to start it
I will let everybody know what I find in the Morning,Again thank you for all the replys

I tend to trust their equipment over your meter - the tests they ran show both unloaded and loaded voltage to be around 14.4 - a completely normal range.

The test shows that your alternator is charging, but it doesn't prove that it isn't causing a current draw when the car is off.

The current draw could be a variety of things - most likely, as Howie pointed out, a latched relay, a light bult that is staying on, a bad alternator, a bad power supply in an amp (or any other electronic component - OEM or aftermarket), and the list goes on.

As long as you are careful you won't pop your fusible link. If you are worried about it disconnect the battery first.

Who installed your alarm? You may want to consider taking the car back to them and having them inspect it. Tell them the problems started after you got the alarm installed and have progressed to the point where the car won't sit over night. They should at least check the draw of the alarm and either confirm or rule it out as being the problem.

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Kevin Pierson

Just a general comment on measuring standby current draw; if you can manage it, connect your ammeter probes across the terminal and battery post before you disconnect the terminal from the battery.

This will give you the actual measurement when it's sitting idle; if you disconnect power, it may wake up onboard circuits that will draw extra current, which results in a higher reading until you wait long enough for them to go back into an idle state. It'll also minimize putting a big current spike into your meter, which caused the spark you got when you reconnected.
It's easy to do with top post batteries, not so easy for side post.

Also the current draw may not be a steady value, with pulsing LEDs and such, so the meter you're using may not give a complete picture.
Does sound like you have some relay or something energized continually on standby, so it'll have to be tracked down.

It does sound like your DMM is wonky, if you read 15V on a 14.4V source. You may want to check it against another meter; normally even the $3 jobs are well within 1/10 of a volt. The only time I've seen them off is when the DMM battery is low; they're not well regulated like Flukes, which allow you to get reliable readings up to the point where you can't read the display any more.