agg714

As for your Battery Tender question, I found an option for the Battery Tender with a cigarette lighter plug. SImply plug the unit into the car's lighter port and you're good to keep the battery charged and healthy. My car will sit for 2 or 3 weeks at a time and the Tender works great. I suspect that you are in need of a replacement battery at this point. The Battery Tender is great for keeping one alive and charged, but can't necessarilly revive a sick one..................................ag

Robin 993DX

Yeah, check your fluids. I remember years ago when I drove my 993 to Pep Boys to buy some car wash stuff I turned the key and BOOM! First I thought, oh man my engine just blew up! Later I discovered that the original battery in the front truck blew up. The whole top lid of the battery came off. Luckily the battery was very dry so there were no acid damage. I guess what had happened was that I didn't ck the battery fluid at all and couple of the cells got really dry and it must have been arcing or something and ignited the hydrogen generated within the battery. So I ended up with a Pep Boys for the next 4 years.

Dominick

Gota,

Autozone must have heard you. I just put my car info into the Autozone web page and it came up with the 48-DL as the correct battery
Thanks for the advice

springgeyser

Multimeter. It should be in everyone's tool box. It can measure low amperage drain and voltage.

As for buying a new battery after it the charge is drained, I would only do it if it does not hold a 'spec' charge. If the liquid filled battery is left drained to long the battery internal plates sulfate reducing the maximum charge it can potentially hold.

For people that have constant battery problems, have they checked to see if their alternator is functioning adequately? I had 'battery' issues with one of my old cars but it turned out a bad alternator never fully charged the battery so the battery got weaker and weaker until...

I guess I am lucky so far, in the offseason my 996 sits in the garage for weeks at a time with no startup issues.

Dominick

Went to leave the house this morning and happened to peak over at the battery Tender. It was solid green light. It took 4 days but I guess she done.

I assume this means the battery might be OK. I'm goin gto pick up a battery tester and mutimeter regardless this weekend

gota911

I just checked the Autozone web page and for a 1999 through 2002 996 it does list the 48-DL. However, when I did a search for a 2003 or 2004 996, the site listed the 49-DL battery. Go figure!

Steven B

Read through this thread this morning, then tried to leave for work and what do you know--Dead, dead, dead! (well it did have 9.07 Volts left.)

Got a 49-DL (thanks, Tim!!) for $90 at autozone and car is starting again flawlessly.

Talk about great timing!

Steven B

Erronious fact: Twas the 48 and not 49.

gota911

You are welcome.

Steven B

A closing note.

A multimeter is a must for any DIY'er. I have one for the garage/house and one for the boat (water and electricity-hmmmm).

Although I have an old Radio Shack model for continuity testing and general testing, I do love my Fluke unit and recommend it highly.

grantq

There's a lot of fantastic battery guides out on the net and it's probably good for people to read one so they understand what's going on with them.

Yes totally discharging a battery theoretically kills some of its capacity, but I've drained some of my batteries up to a half-dozen times and they generally enjoy full 5 year lives.

i have a battery tender I bought for my motorbikes, but of course it will work on a car battery since they're the same except larger. it will monitor the voltage and switch to a pulse mode when the battery is full to avoid overheating. It also claims to "de-sulfate" the plates with the pulsing. This may or may not be hocus-pocus but as I said my abused batteries live long lives.

If you are buying a multi-meter to test your battery, do confirm it includes a specific BATTERY TESTING mode. Simply checking the voltage across terminals only tells half the story, i.e., how charged the battery is. It does not tell you that if the plates are heavily sulfated, that seemingly healthy 14.3v differential will drop to a useless 10.5v differential as soon as load is applied. Battery Testing mode will apply a slight resistance when testing the voltage so you can determine if it's actually going to give you power. From what I recall, a voltage of 13.0v+ in this mode means a useful battery.

One of the strange things I discovered in my research is that if your "12 volt" battery is really only delivering 12v.. then it's toast.

Steven B

Indeed, this is true.

There is more information than you wish to know in the boating literature. Suffice to say, the loads and care of batteries is of paramount importance when sailing--no alternator running all of the time. Actually, as you note, a voltage of >13 V is fully charged and 12.2 is pretty dead.

OK, off to see a daughter in NYC!

marky522

IF you have a battery that will hold 13+ volts you have some magic there A car battery is a 6 cell battery capable of holding 2.1V per cell, connected in series gets you 12.6V A fully charged battery, with the surface charge removed is 12.65V actually. If your battery will only hold a charge of 12.45V or less it is bad. If you charge your battery, you need to remove the surface charge by applying a load for a few seconds (i use headlights for about 15-30seconds) because you will get an adverly high reading.

Make sure you know what you are doing when you are going to start looking for a draw, your meter needs to be connected in series with a battery cable, but you cannot break the connection between the battery and cable. The car has many control units which stay "awake" for a period of time once the car is turned off, you need these units to be turned off BEFORE you place your meter in series with the battery or you will blow the fuse in your meter. And if you break the connection while connecting your meter the units will all wake back up. Confusing huh!!!!

Mark

GMS

Quote
"Yes totally discharging a battery theoretically kills some of its capacity, but I've drained some of my batteries up to a half-dozen times and they generally enjoy full 5 year lives"

We recommend to all our customers that batteries have limited lives and should be changed after 5 years or so.

marky522

I wish most of our customers made it to 5 years!!!!

Mark