Electrical system draining battery
 

Here's the scoop.

I purchased a wrecked 2005 6-speed RX8. I put a new battery in it while it was at the body shop being repaired. The car ruined this battery while it was still sitting in the repair shop. I just assumed that the people there left something on in the car. I replaced that battery with a new one, and it has since been repaired and has now been sitting in my building for a little less that two weeks waiting to be inspected for proper repairs. it cranked and ran fine when I put it in the building, but then I noticed today that the battery was drained, but no one has been using or fooling with the car since I put it there. I'm at a loss of where to start looking for a short or for what would be drawing power. Thanks.

Okay..................the current draw with the car off should be about 50mA or less. Do you have a meter and know how to check that?

Also...................any aftermarket eqiupment on this car?

It's not that unusual for these cars to drain the battery for those who put it in storage for the Winter, but two weeks is really fast. I assume the "new" battery was 100% new?

If you are not running anything special while the engine is shut off, there still will be a very small current drain--sometimes referred to a dark current--which should be in the neighborhood of 20-50 milliamps (mA). Things like the clock, radio button settings, and other housekeeping systems are responsible for this drain. A healthy battery should last for several weeks before dying in this case.

If you are running an aftermarket audio system with a big amp and speakers, the draw will be significantly greater than that and just how long it would be before the battery dies will depend on the specific current draw and the duration of the draw. If the draw is say 10 amps, a fully charged, 50 amp-hour battery would theoretically last for 5 hours before dying.


Here are a few things I have heard of that can drain your battery.

1) Trunk light on.............meaning trunk is not shut ot light has stayed on. Look through the passthru in the bakseat and make sure it's off.

2.) Dome light left in the always on position.

3.) Bad alternator just not recharging the battery.

4.) I've heard of a fuel relay also staying on and draining the battery.

5.) Make sure your battery terminals are clean and all connections are tight!


First step besides #1 and #2 is still getting the off(dark) current draw read.

Ok, sweet, I will check/try these things you have suggested. I'm very grateful for your help! Thank you kindly. I'm new to the rx8 and newer cars with sophisticated electrical systems in general, so I'm trying to learn as much as possible. By the way, the car is all stock (as of now...) and I'm pretty sure it was a brand new, off the shelf battery. I'll go see if these make any difference. One more question; is there a glove compartment light? Thanks again.

Yes there is..........but as stupid as it sounds, you have to have your lights on for it to work! :banghead:
This has actually come up before and been asked a few times. I'll never understand why Mazda would do that. :uhh:

hit me up if yor anywhere around annadale or alexandria.might be able to help trace your problem down.

I also have had battery draining problems
 

I don't have any answers to the problem, but I also have had battery problems that one would not expect.
Oct 2004 bought new AT RX8.
Sept 2005 battery died after parking for 4 days in airport car-park, battery replaced under warranty.
Aug 2007 battery drained after 3 days in airport car-park - recharged OK.
May 2008 battery died after two weeks in home garage, battery replaced again under warranty.
Something does not seem right with all this battery draining, not only that, two batteries actually died and could not be brought back to life ???
The tech at the garge today told me that this was not uncommon with RX8's but he could not explain why ??

to add to mazsufers points.

if you have a stock navi system the dvd drive is know for this issue.

beers :beer:

Oh, that's a good point..............I forgot about that one!

dotn forget the bose amplifier not turnignoff.... i had mine replaced because it drained my battery

Jeez..................we better start a list somewhere! :eyetwitch

Highly recommend to change to Optima Yellowtop - this car needs too much current when parked, even when everything is fine, and the OEM batteries are all weak. I had 3 in the car already before I gave up replacing them under warranty and forked the money for a real battery.

Maybe, but on the flip side, I've had the same battery since new in December of 05 with no issues at all.

funny it happened to me today.

would barely spin the engine.. did not flood. was able to jump it with my motorcycle.. have no idea why it happened..

i guess i will see if it is an issue tomorrow.

beers :beer:

Need H
 

Hey, I'm in Dumfries, VA. I just bought an 05 RX8. I could use your help getting it started. It cranks but won't start. I've called every mechanic in my area but no one works with the rotary engine. PLEASE HELP!

He hasn't been active since 12/08.
There are many common reasons for them not starting, try reading the Troubleshooting threads.