Question for the electrical wizzards (1 Viewer)

bj40green

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This is not about my BJ40 but about my other car a 2007 Daihatsu Terios, Full extra's, Automatic, All Wheel Drive. Also know as Toyota Rush.
DSC04090.JPG
There is no forum page for this model so I post it here in the electrical section.

The question is: How much current is drawn from the battery when everything is switched off.

I have a FSM but the answer is not there. There are a lot of circuits "stand by". To name a few; radio memory, alarm system (blinking led's), remote controlled door locks and more.
A lot of circuits are not switched off by the key but are controlled by computer chips (ECU's) with memories that are kept alive by a direct battery feed.
The point is that I think that I have an excessive drain which causes the battery to go dead in 5 days when I don't drive it.

I was at the Toyota dealer today and they could do a quick check so I said OK.
After all, I only wanted to know if the current draw was out of spec.

Next thing that happened was that he was covering the steering wheel with plastic, the driver seat with a plastic cover, a magnetic number on the roof so I asked him what was going on?
The answer: We need two hours for the diagnosis to figure out what was going on.
Well, I know their price list so I cancelled the whole action.

Can anybody point me in the right direction. Any help is welcome.

Rudi
 
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Well, the answer to your question is not a lot... I imagine something well below 0,5A... Time to get a new battery?
 

bj40green

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Well, the answer to your question is not a lot... I imagine something well below 0,5A... Time to get a new battery?

The battery was dead this morning after several attempt to recharge it yesterday. So I jumped started from my Cruiser this morning with really big fat jumper cables and went to the battery shop to get a new battery. I got a discount because the battery was only 13 months old.

That raises a new question; how much is not a lot?
I've checked with two DC Amp meters and it's 120mA (0.120 Amp)
A little calculation tells me:
120mA per hour = 1.2Amp per 10 hours = 12Amps per 100 hours.
100 hours is 4.16 days.
The battery is a 40A/h type so after 4 days i've lost 12A/h, which is more than 25% of it's capacity.

Right now I'm monitoring the voltage 3x per day to see what happens when I don't drive it.
This evening the voltage was 12.4 V after a 3 hour rest period. Time will tell.

Hmmmmmm,

Rudi
 

Tapage

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if you have identify those circuits that still have draw even with switch off ... you can pull those circuit fuses and measure each one separately ..
 

hj 60

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My Mitsubishi with stop&go has 65 amps (so small car, big battery)
And for 7 euro I bought a obd bluetooth Version 2.1 tool that you might like.
It comes with cd software (no trial) plug and play, very funny info about ecu, not really related to draining the battery, but might give a broken sensor.

http://www.ebay.com/itm/Mini-ELM327...576?pt=LH_DefaultDomain_0&hash=item27e13a8df8


From the cd, the software for android , 车况监控_Torque_Pro_V1.6.10.apk

https://docs.google.com/file/d/0B6D936BcfemZZHppblBPR3duVGM/edit?pli=1
 
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Your calculation appears sound. Many new cars will run a battery down in a week or two if not used, especially one with small batteries.

Was this a problem in the past?

I would test the battery if this is a new problem, if it's a ongoing issue, a larger or upgraded battery would likely help, but room may be an issue.
 
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Most new car specs are 50mA allowable draw from high electronic vehicles like Cadillac, high end Euros like Audi and Touareg, the expensive s***.

Typical everyday economy car with standard electronics is allowable draw of 40mA.

Things to keep in mind when you're testing is that a lot of vehicles take up to 20 minutes to go to "sleep" and reach the minimum draw, sometimes even longer depending on programming setup. Also testing the draw it is helpful to leave everything connected in order to isolate the circuit at fault, search out a fuse matrix chart and it will tell you mV conversions to Amp draws across the fuse you're measuring. Good luck, most of the time it's a module not properly shutting down so isolate circuits one at a time.
 

bj40green

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if you have identify those circuits that still have draw even with switch off ... you can pull those circuit fuses and measure each one separately ..

Yes, I can do that but I still don't know the acceptable current draw. I'll have another look at the FSM.

Your calculation appears sound. Many new cars will run a battery down in a week or two if not used, especially one with small batteries.

Was this a problem in the past?

I would test the battery if this is a new problem, if it's a ongoing issue, a larger or upgraded battery would likely help, but room may be an issue.

I don't know when this started. I discovered it because my wife and I changed our drive pattern.
I drive my Cruiser daily and my wife drives the Terios now and then. The Terios stood parked for 3 weeks or so and gave not even a click from the starter relay, so the battery was really empty. I jumped started from the Cruiser and the Terios drove fine but one week later (last week) we had the same problem. I put it on the charger but it charged only 2 Amps and indicated that the battery was full at 14.4V. NO STARTING so another jump start and on my way to the battery shop. They tested the battery with a load tester and the result was: defective. The guy checked the acid values for each cell but they were OK.

Most new car specs are 50mA allowable draw from high electronic vehicles like Cadillac, high end Euros like Audi and Touareg, the expensive ****.

Typical everyday economy car with standard electronics is allowable draw of 40mA.

Things to keep in mind when you're testing is that a lot of vehicles take up to 20 minutes to go to "sleep" and reach the minimum draw, sometimes even longer depending on programming setup. Also testing the draw it is helpful to leave everything connected in order to isolate the circuit at fault, search out a fuse matrix chart and it will tell you mV conversions to Amp draws across the fuse you're measuring. Good luck, most of the time it's a module not properly shutting down so isolate circuits one at a time.

This is good info, especially about the shut down time. I have a job to do tomorrow.

Thanks to all, I'll keep you posted.

Rudi
 
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Someone you said previously has be a concerned.

So it wouldn't start the vehicle but when you hooked up a tester it passed and said 14V? There is no way you should have anything more than 12.8V with a charging system running.

Secondly just testing the acid value of the battery isn't the greatest test, an electronic load tester or an old school tester that lets you increase a carbon pile on the battery is a much better gauge. I'm almost starting to wonder if you have a loose plate that is moving around causing erratic test results....
 

bj40green

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Someone you said previously has be a concerned.

So it wouldn't start the vehicle but when you hooked up a tester it passed and said 14V? There is no way you should have anything more than 12.8V with a charging system running.

Secondly just testing the acid value of the battery isn't the greatest test, an electronic load tester or an old school tester that lets you increase a carbon pile on the battery is a much better gauge. I'm almost starting to wonder if you have a loose plate that is moving around causing erratic test results....

I think you read my earlier posting wrong but to make a long story short.... The battery was replaced after the load and acid test.

This morning I hooked up my DMM in series and noted that from the moment everything is "off" and all the doors closed that;
- It takes 12 seconds for the interior light to shut down.
- From this shut down moment the current draw is 330 mA for 5 seconds.
- After these 5 seconds the current draw goes down to 120 mA. At this point the time lapse is 12 + 5 + 5 = 22 seconds.
- From this 22 seconds point it takes 60 seconds to go down to less than 10 mA. My DMM is blinking 0.01 and 0.00 so it must be a value in between.

I'm happy with this result. :bounce::bounce2:

Rudi
 

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