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I was reading the 991 SIT link which was provided by one of the members and came across this Porsche recommendation why it’s not a good idea to connect to the negative terminal to charge/jump start your battery.
I agree with this because when using a jumper cable on another car running to charge your dead battery, or a 20 to 30 amp HD battery charger can cause voltage spikes. A 12.5 to 13.5 volt battery tender with 2 to 4 amps of charging current connected to the B+ battery post and Negative battery post will not cause damaging voltage or current spikes.
Agree, would like to see one, and using OBD seems more of a hassle than other methods (at least on the .1 because you have to remove the fuse cover).
I would rather deal with the "hassle" of removing the fuse cover than have a cable flopping around under the hood with the possibility of causing a short. After pulling in the garage I open the door, from the driver's seat I grab the charging connector laying on the garage floor, pop open the fuse cover and plug it in. It's that simple and there are no worries of 12v outlets being powered down.
I will be happy to post a picture tonight if it will help.
I would rather deal with the "hassle" of removing the fuse cover than have a cable flopping around under the hood with the possibility of causing a short. After pulling in the garage I open the door, from the driver's seat I grab the charging connector laying on the garage floor, pop open the fuse cover and plug it in. It's that simple and there are no worries of 12v outlets being powered down.
I will be happy to post a picture tonight if it will help.
You have an incorrect mental picture of the connector that the direct battery hookup uses., It isn't a cable "flopping around" with the possibility of causing a short. Somehow the designers of the product realized that would be a bad idea. Instead the connectors are nested inside the housing to prevent accidental contact and have a water-resistant boot that stays closed when not in use. Here's a couple of photos I've taken after pulling it up front under the edge of the hood. It's about as accessible and safe as you could get.
Finally hooked up the Deltran Battery Tender today and installed my new car cover for the winter. I connected the negative alligator clamp to the negative body grounding point and connected the positive alligator clamp to the positive battery terminal. Then, I passed the charging cable through one of the grill holes on the black plastic cover and carefully reinstalled the lid, checking with a flash light to confirm that the connections were still in place prior to pulling the black rubber weather stripping back over the front of the plastic compartment cover. I ran the power cable up toward the windshield and passed through that depressed trim area near the wipers to get a good close of the hood with zero cord compression or contact. All good here!
On a somewhat related note - not using any trickle charger, Will the battery retain significant charge if parked outdoor in driveway for 3 weeks , and a good long drive after that should revive that , correct ? Cold northeast
You have an incorrect mental picture of the connector that the direct battery hookup uses., It isn't a cable "flopping around" with the possibility of causing a short. Somehow the designers of the product realized that would be a bad idea. Instead the connectors are nested inside the housing to prevent accidental contact and have a water-resistant boot that stays closed when not in use. Here's a couple of photos I've taken after pulling it up front under the edge of the hood. It's about as accessible and safe as you could get.
This is how I have it in my car too. Don't have to open any door or trunk lid, or pass through any weather stripping. This solution has worked very well for me. I don't have to open the car to connect or disconnect the setup and I just put a "remove before flight" tag on the starter dummy key to let me know the charger is connected.
Only visible when I pull it out for charging and it's an always available direct connection to the battery. You could potentially check battery voltage or charge a USB device using the accessories Deltran sells that connect directly to the pig tail I have hard wired to the battery. I have the Porsche Tequipment charger but consider it a hassle to have to have it connected to the 12v socket in the passenger footwell since I park my car very close to the right side of the garage.
OBD port charging connector is the way to go in my opinion.
I've not seen one of these.....but I'd prefer not to connect a battery charger to the car's OBD II port. As direct as possible to the battery seems better. Imagine a third party manufacturer's charger taking a crap while connected to your OBD II port! Not a warranty scenario I'd like to be engaged in.
I am planning to hook-up one of my existing Deltran Battery Tenders to maintain the battery.
I plan to aligator clip direct to the battery. Safe to connect the negative directly to the negative terminal of the battery or should I connect to the body for ground?
Since you are using a Battery Tender which has an SAE connector to connect the alligator harness to the charger, you can connect directly to the battery.
You connect to the battery first and then connect the charger's SAE connector.
This has nothing to do with boosting the battery diagram in the manual.
I know the thread title says for 991.2, but, I leave my '13 991.1 in Scottsdale during the winter. I was last here in early December. I plugged the Porsche branded CTEK into the socket in the console. Returned last night to a totally dead battery. Stupid me. I didn't notice that when I plugged it in, the status light on the charger did not light (power light was on). I had an alligator clip to lighter adapter and hooked it up overnight and it charged the battery.
So, I found that the two lighters in the car (console and passenger footwell) do not connect.
That's interesting because the footwell outlet in my 2015 991 is powered when the car is off and I have my tender plugged into that location based on the recommendation of the dealer where I purchased the car.
Hardwire to battery and then you don't have to worry about the sockets. There are varying posts about sockets not working on some cars for whatever reason.
01-14-2019, 11:39 AM
