[s-cars] Battery question....(this is driving me crazy)

[CyberPoet]

Clayton,

  Your original battery may have been failing because it wasn't being
properly charged across the whole RPM spectrum (i.e. - borderline
alternator, borderline rectifier, etc), in which case the battery
failure was symptomatic of a different problem. If this is the case,
then the replacement of the battery would cause these things you've
mentioned to fail as well (most or all are symptomatic of insufficient
voltage in the system, even with adequate amperage). Three thoughts:

1. Check your voltage both at the battery with the car off and at the
cigarette lighter with the car running at various RPM's (i.e. - idle,
1k, 2k, 3k). It should read at least 12.2 with the car off and at least
12.8 with the car running (anything up to 14.2 is acceptable, and 13.8
- 14.2 is fair with a healthy battery when measured at the alternator's
rectifier itself when charging).

2. If you have to replace the battery again, seek a marine grade
battery with the appropriate drainage. The difference between regular
automotive batteries and marine grade batteries has to do with what
happens when the battery deep discharges -- traditional car batteries
lose somewhere around 30% of their starting power each time they are
deep discharged; marine batteries lose about 1% due to a deep-discharge
cycle and are designed to handle repeated full cycle discharge/recharge
cycles. Cost difference is normally less than 10%.

3. Always test your alternator's output whenever you replace a battery,
as you have at least a 25% chance that the battery failed for some
reason other than the battery alone. This is even more true in Audi's,
where the battery is traditionally sheltered from the heat and
vibration of the engine compartment.

Remember the automotive battery rules:
1. Cold robs a battery of it's ability to produce power on demand, but
heat is what actually kills a battery.
2. Automotive Grade - 3 deep discharges = death; Marine Grade - 80 deep
discharges till no start.

Best Wishes,
=-= Marc Glasgow
Tampa's best Mac Consultant since 1990
www.cyberpoet.net

Clayton Wrote:

Not too long ago, I replaced my stock battery with a new optima red top.
Very shortly afterwards, I lost the sunroof (it closed for me one last
time
and hasn't done anything again).  Then about a week down the road, I
lost my
ABS switch and both front heated seat switches.
So, all together I have lost power to my ABS switch, pass. heated seat,
pass
and driver heated seat switched, and the sunroof.
Can anyone tell me if these are related to the battery change or just
timing?
If there something I should be checking as if something has shorted or
anything along those lines?
Is there a way to test my theory on the battery (I had to recycle the
old
one)?
Please help me out on this, the ABS light drives me nuts and how can I
enjoy
the sunshine with a close roof?