Battery draw - Mitsubishi van - 100 mA

[domwild]

Hi,

As the service manager of the dealer I bought the vehicle from did not answer my query re draw on a "switched off" vehicle I will have to turn to this forum for an answer.

Vehicle: Mitsubishi 2.0 litre petrol van, 1.5 yrs old. After two weeks of just standing there the battery was completely flat. The only consumption is the clock and the "thief warning LED" on the radio. A check revealed a draw of 100 mA with the ignition switch off, i.e., parking mode.

Any ideas if this is too much and I should get this fixed up under warranty?? One suggestion was that the diodes in the alternator are conducting in reverse and causing this draw. This electrician said the draw should only be about 20-40 mA.

Thanks.

[RP]

Pull fuses one by one until the draw drops to zero.  Then you'll know which circuits or accessories are the culprits.

[drdongle]

I second that, and the alternator diodes sould be in the microamps ( uA).

[Countryboy]

100 mA for 24 hours a day, for 14 days is 33.6 Amp hours.

Either you have a drain larger than 100 mA, or your battery is unable to hold much more than 33.6 Amp/hour of charge (ie, the battery is junk.)

If you have a good compass, move it around all over the auto.  If you have a short, it will create a small electromagnetic field which will interfere with a compass detecting the earth's magnetic field.  If you hold a good compass near a short, the needle will be all over the place.

[Nando]

There are some car or van that draw more than 100 ma when standing still.

I have a BLAZER and I have installed a connector to place the battery in float mode to make sure that the battery is not flat in few days since sometimes I travel for more than 2 weeks and the same for a daughter that her trips may last 3 to 8 weeks, I used a small float charger sold by Harbor Freight -- they come on sale often .

Nando

[nanotech]

This is very sound advice.

Then again, so is CountryBoy's statement of the condition of the battery.

[Warrior]

I also think the battery is shot.

I was on a trip once that lasted a month. The car wasn't started not even once during that period. I put jumping cables in the trunk before I leftthinking the battery would drain but to my surprise the car started on my return.

The same thing happened when the engine broke down and was in my garage for about 4 months. I did disconnect the battery this time, and when I finished putting the engine in, it also started right away, without even recharging it. Amazing the battery is 4 years old! And still running, honest...

Buy a new one, try to get a good brand and with the highest amphours possible.

Warrior

[elvin1949]

 Does it have a light under the hood.

If so check the switch that turn's it on when you

raise the hood.If it sticks it will kill a battery in a couple of day's.[been there done that]

later

elvin

[Nando]

Again

if the current is 100 ma and run for two weeks

0.1 amp * 24 hours * 14 days = 33.6 amps drawn

What is the battery capacity ?.

Battery may be with lower storage capacity or even shot.

Lastly the alternator may not be charging the battery fully.

Nando

[jimjjnn]

Also check the trunk (boot) Light.

I had one that also failed to turn off. Old style mercury switch had broken.

[domwild]

Hi,

Thanks for the many replies and suggestions. I will try all the suggestions. This will also be a test of how good the manufacturer's warranty is on new cars.

dom

[stephent]

Clean the battery cable ends good.

Check to see if each is terminated good at either ground or the solenoid (starter).

Late model cars/trucks are computerized of course--the computer will draw more then a few mills while the key is off.

Led's usually draw 15/20 ma or so each.

Also check the various door switches that operate dome/interior lighting. I have an old Van that has fancy interior lighting and it's not so good with the fuses in--short somewhere?

A 1 or 2 year old vehicle battery should still be able to do at least several weeks before it "appears" flat. But flat to a newer vehicle computer will be just a little under the normal 12 volts out --10 volts or so. The computer is still working, but won't engage starting "stuff" since it's more then likely protected by a voltage level detect circuit.

[Clifford]

Your battery probably is rated at about 100 Ah (or less) new....

So, if you drop by 30 Ah...  you have lost about 1/3 of the "new" charge.

As far as volts...   12.6 - 13 volts is "full".  

10 volts is considered completely discharged.

Any vehicle should be able to sit for a few weeks at a time.  

However, if you frequently leave your vehicle sitting for 1+ months, consider getting a battery disconnect.  They only cost $5 or so and are quite effective at preventing the battery from being killed.  Just flip the disconnect switch whenever you park your car for an extended period.

[adelaide]

common for power to imobalizing relay to be wired to constant power insted of ignishon. is a posability alarm should use 10 to 20 mah , bonet swich may if has 1 may turn on a interia light some whre to , clean top bat to. all may help / if bat back up siron ,is common for them to die and try to chage siron too , more to test , like they said try fuses  alarm prob tapped into wireing behing key