dcdude

I believe that it was a Battery Tender (not Jr.) that failed to bring back a flat battery on my Bronco. To revive it, we used a big boy charger from Harbor Freight like this one: http://www.harborfreight.com/cpi/cta...emnumber=45005 Worth a shot before trashing your battery!

IXLR8

Thats when it is time to connect a charger again.

Batteries should be between 12.65 and 12.85 volts fully charged. Some newer chemistries will see as high as 13.2 volts.

Of course, during the charging cycle, most batteries should be charged to 14.4 volts before being switched to a float mode of 13.2 to 13.6 volts, give or take.

CADguy

Sorry, but this is not necessarily the case. I bought the CTEK 3300 (same as the Porsche branded unit) for the 993. I had an older PU truck that I let the battery go completely dead (not even the battery solenoid clicking) due to not driving it for several months. It took several days (maybe up to five), but the CTEK 3300 brought it back to life!

Bottom line, once the light on the charger goes from amber to green, the battery is fully charged and will then be maintained at full charge.

verhag

New optima red top installed...all is good...except....

1) do I begin using the brand new, but suspect, Porsche branded ctek battery tender with the brand new battery ? A little nervous about doing this but I find it hard to believe that the Battery Tender was the problem...it's just so odd that the first time the car would not start was after an overnight trickle charge with the new unit.

2) return the Porsche battery tender and just plan on replacing the battery every couple of years like my brother does with his 964?

and by the way...Thank you for all the advice.

Denny

Slow Guy

To answer your question, No, they are not. They only put out 1.5A max and you would nee at least 6 (10 better) amps for that purpose.

I have both BT for the everyday stuff and a 2/10 Amp Sears charger for the special occasions.

IXLR8

So do I, but then I'd test it to be sure.

Connect it to your battery and then monitor the battery voltage every half hour. It should increase till about 14.4 volts and then reduce to the mid 13s.

ezinternet

Guys - Is everyone certain that the CTEK/Porsche can charge a 993 by way of the cigarette lighter?

I know it works on the 997.

I thought it *did not* charge via cigarette lighter on the earlier 964.

Just asking.

Robert993TT

I have done so for the entire time I have owned my 993tt without problems. One just have to make sure that the contact is fitted correctly. Otherwise the battery will not get any maintainance charge. One notice quickly if something is wrong. The charger will tell you if something is wrong. The contact that is fitted to the cigarette lighter is not entirely correct in size for the 993 in my experience. I don´t think they make two sizes. Haven´t done any further investigations with CTEK.

CADguy

I also have used the CTEK 3300 all last winter and this winter so far with no issues. Yes, the cigarette adapter doesn't seem to fit perfectly, but it does make contact good enough to charge the battery through the cigarette lighter.

Once again, if the battery voltage is low enough, it will take several days to bring it up to full charge.

IXLR8

I just downloaded the manual for that model.

It does not have automatic temperature compensation, but it actually has a selectable mode switch allowing for a higher cut-off voltage as required at lower temperatures. That level is also required for the Odyssey and some other batteries.

Nice. I haven't seen that on any other commonly available chargers.

JPP

I bought a Porsche Battery Maintainer from Sierra Madre last year for my '95 and have had no problems leaving it plugged in for months at a time.



http://www.sierramadrecollection.com/store/cart.php

Just before Christmas, the bodyshop where my car was being worked on left my engine lid open overnight and ran the battery dead. They hooked it up to their big boost charger and it fired right up, I drove it for the next 2 weeks with no problems. I suspect your battery was on the way out and that's what caused your problems.

ltc

I charge my wife's 993 Targa via the cigarette lighter using an OEM Porsche Charge O Mat (the one before the CTEK unit came out), shown in the above post/picture.
I also have one for my 996Turbo and charge it from the cigarette lighter.

IIRC, I can also charge my 964 Cup Car from the cigarette lighter.

ezinternet

Weight of experience and opinion supports charging via the cigarette lighter. I'm happy and relieved that I can stop having to route the cable out of the front trunk.

Cactus

[QUOTE=JPP;7191837]I bought a Porsche Battery Maintainer from Sierra Madre last year for my '95 and have had no problems leaving it plugged in for months at a time.



http://www.sierramadrecollection.com/store/cart.php

Same one I have used for the last 2.5 winters.

Brucechas

Just a thought because I ran into this on my 75 911S, the cig lighter port was not hot...in other words, the lighter would not work if the ignition was not on, so power will not make it's way to the battery. Hope you don't take this wrong but that was my situation, so I use the accesorary battery clamps.