Battery quickly becomes low

Alexander B. Sonin

Alexander B. Sonin

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Hi
On my 98 Mark VIII battery quickly becomes low.
Leakage power of 0.25 A
Did Anybody had such a problem and how to fix it?
Thanks,
Altxander.

Sorry! 0.25 A
Battery becomes low after 4-5 day, 11.8 V.
Not being started.
 
0.25 ma or 0.25 a - 0.25 ma is pretty much nothing. I have not tested my car, but, I'd expect it to be around 20-30 ma at the minimum based on car and the electronics.
 
How old is it?

Does it sit around alot w/o being started?

What's the resting voltage?


Take it somewhere and have it tested.
 
You could take it somewhere to be load tested or just meter it on the battery post while a friend holds the gas pedal down (cuts off fuel to the engine) and cranks the starter/engine over. if there is more then a 20% drop in voltage it might just be the battery on it's way out. If not then you have a drain somewhere.
 
what i have found is simple. the alternator has regulator internal, found the same thing in mine. went bad, caused a constant draw on my battery which caused the battery to go bad.. simple way to test.
put volt meter on battery and pull the plug on the alt. if the voltage comes back up thats the problem.. (car does not need to be on or running) this will tell you if the alt is causing the draw..
 
You shouldn't have more than .04 to .05 amp draw on the battery. Alternator, radio amp or power seats are the most likely things to cause a draw, but it could be anything. Another check for the alternator is to stick a screwdriver next to the alt pulley, if it's magnetized and sucks the screwdriver to it, it's probably causing a draw. You live where it's cold out, so if you don't start the car for 4 or 5 days, battery is probably getting old and doesn't want to hold a charge.
 
My 95 and my 98 were sitting out in the cold, with newer Bosch batteries and both went dead. Now I dis-connect them if their going to be out in the cold. These MK VIII's are hungry even if there not being used. Both bats took a charge and are good.
 
96_Lincoln_LSC said:
what i have found is simple. the alternator has regulator internal, found the same thing in mine. went bad, caused a constant draw on my battery which caused the battery to go bad.. simple way to test.
put volt meter on battery and pull the plug on the alt. if the voltage comes back up thats the problem.. (car does not need to be on or running) this will tell you if the alt is causing the draw..
Click to expand...
Hi, nice to see you back, hope everything is going good for you!
 
I assume you've pulled a battery cable and placed a meter between the cable and the battery terminal since you know what your parasitic drain is. Now watch the meter while pulling one fuse at a time to isolate the problematic circuit(s). You'll know you've found the source of the drain when the current drops significantly.
 
.25mA (.00025A) would be far too low. 25mA (.025A) would be about normal.

.25A (250mA) would be a serious drain.

Quite possible one of the diodes in the rectifier (inside the alt) is failing, causing the drain. Any parts shop should be able to load test it to verify.
 
SATURN5 said:
.25mA (.00025A) would be far too low. 25mA (.025A) would be about normal.

.25A (250mA) would be a serious drain.

Quite possible one of the diodes in the rectifier (inside the alt) is failing, causing the drain. Any parts shop should be able to load test it to verify.
Click to expand...

And make sure they do it multiple times. Pulling it off and taking it inside to the more accurate machine is a good idea. This alternator is super easy to take off. One good test with these alternators doesn't mean it's good. On the third try mine failed, the whole time I knew the alternator was bad.
 
Put me a chi-knee reman unit from o'reilly's yesterday. No time to take mine in and get rebuilt.
 
Already returned my core. Plus that's not what oreilly's is there for. They aren't a library, they aren't in the business of loaning parts out.
 
The regulator was failed. Id bet money the honcho en Mexico O'Reilly Auto parts alternator has the same Chinese voltage regulator that my local rebuilder would have installed in my factory case.
 
-stew- said:
The regulator was failed. Id bet money the honcho en Mexico O'Reilly Auto parts alternator has the same Chinese voltage regulator that my local rebuilder would have installed in my factory case.
Click to expand...

Not a quality rebuilder. They know where to get the "good stuff". ;)
 
It's not an O' Reillys alternator, but my $100 ebay special is going strong 3 years later...

Not all alternators that aren't oem or built w/ premo parts are junk.

Stew- I hope it works great for ya.
 
driller said:
Not a quality rebuilder. They know where to get the "good stuff". ;)
Click to expand...

I wish that was true. But with the state of American manufacturing, I'm gonna guess who ever is doing the rehaul, is tossing in the cheapest parts they can find. Plus I doubt there are even many, if any, options for different voltage regulator manufacturers.

Lownslowlsc said:
It's not an O' Reillys alternator, but my $100 ebay special is going strong 3 years later...

Not all alternators that aren't oem or built w/ premo parts are junk.

Stew- I hope it works great for ya.
Click to expand...

Thank you and thank you.
 
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