96 850T Ignition Switch Battery Drain ?

[socalover]

Hi all,

To start off I'm very mechanically inclined.

My car started having a battery drain issue about a month ago. I was prepared to replace the Alt as my battery is less than a year old. I took it to a shop and they tested it and said the Alt and battery are fine. Just my cables needed cleaning and the negative wasn't on tight enough. They charged my battery for me and I was happy. About 5 days later battery didn't have enough power to start the car all though if I get a jump it's fine. I spoke to a friend that is a mechanic and he said it could be the diodes in Alt are going bad and pulling juice from the battery when I'm not driving. What do you guys think?

Here's some things I've noticed about the car. My ignition switch is wearing out. I have to tap the keys to get my lights on or shift out of park. Yesterday I turned my car off and the radio stayed on until i pulled the key out. Weird. Also I don't remember that my radio anti theft light blinking once I engage the alarm. I thought it used to go off. Could the radio or ignition switch cause a battery drain since they are not functioning properly? All my fuses are good. For now I can do without auto lock/alarm and/or radio if I have to. Thoughts please.

[scot850]

You may have 2 issues going on. I'd replace the electrical portion of the ignition switch for sure, but there is a problem that comes up from time-to-time with faulty alternators. They test ok, but they fail. I can't remember the issue exactly, but they cause a drain down of the battery. You could do the switch first to see if it is leaving something live by not shutting down correctly, and if you still get a flat battery, I think the alternator has to go, unless someone can tell you how to fix it.

Neil.

[BEJinFbk]

Why blame the alternator without being sure?
I agree about swapping in a new set of contacts
for the ignition switch, but it's also possible that
you battery is going flat due to parasitic drain or
a cable/connection related charging system issue.

Go for the cheap, easy stuff before you start forking
out the bucks for an alternator. Search "voltage drop",
"alternator testing" and "parasitic drain" to get started.

[socalover]

Thank you both for the advice. I'm going to get the ignition switch replaced first since I know for sure it's wearing out and I'll have to do it eventually. Any thoughts on the radio anti theft light blinking after I've armed the alarm system or was I just imagining that it used to go off before? I have all factory equipment.