Using existing battery connections for CTek tender

On my 2017 F premium, was advised by the Jaguar technician to connect the positive eyelet on the Ctek tender to the positive battery ‘bracket’ that is under the red plastic cap. There is a perfect spot, a small @ 12/14 gauge black/red wire is attached, and there is a bolt there that I can use for the positive connection to the tender. The tech also advised connecting the negative wire of the tender to the negative ground bolt on the floor of the trunk. It appears to be double nutted.
Questions: 1. what is that little black wire for, and if I loosen the nut that is holding it to attach the eyelet for the tender, is it likely to do something to the car? (I know about the window thing up/down 5 times. etc.) 2. To connect the negative eyelet for the tender, will it suffice to just remove the top nut on that ground bolt, insert the negative eyelet and then refasten the nut? I’m used to the battery and electrical on my 69 E, not so much for this AGM battery.

I also have a 2017 F, and have used a Schumacher tender. The electrical connectors may be different? What I did is to make a positive connection on pos. t bar where there was an extra bolt.On the neg side went directly to neg terminal. the nut does not come off so used a open-ended connector. Hope I am clear enough?

Hi and thank you for your help! Yes, the Positive T bar…I don’t have the extra bolt, just the empty hole. The other hole has that 14/16 gauge black/red wire that goes somewhere. If I knew what size the bolt hole is, I’d get one and use that. My tap/die kit doesn’t have metric and the US battery bolts are just a bit too small. Thinking of just going to box store and buying a couple of this and that Technician said to put the neg eyelet on the ground connection on the ‘trunk’ floor. Not sure what an open-ended connector is, probably will recognize it, just by different terminology. If you have a photo of what you did, I could compare it to what I have. Just don’t know what is consistent with these Fs… even by MY. I know in the ‘old’ days, the factory would pull parts from whatever bins for whatever they needed. My 69 E is supposed to have a ‘cell’ battery for the clock, but it doesn’t,… it’s still a car battery connection. It was an August build, so who knows what was available at that point.

The open-ended connector is shaped as a “U” vs an eyelet “O”. Should not make a difference if neg. side is connected directly to the battery or common ground. In my case, it would have required a longer wire extension to reach a body ground.
My father’s 69 E had the battery in the clock, my 70 is wired into the system.
It has been my experience with Jags that the model year is not a definite cut off point.
Believe if there were leftover parts on the shelf they used up the inventory.

HI Glenn and thank you again for your time. Yes, I do know the U shaped connectors. The Ctek unit has nice sized eyelets that will work. Was trying to figure out what size bolt to use on that empty threaded fitting on that T bar. Found a 5/16 Fine that started, but wouldn’t go all the way. Put on my “RoadKill” pants and just tapped it for that bolt. So I have the positive side of the Ctek lead on. I taped up the negative eyelet until I work through the negative side. Not feeling comfortable about taking off
the nut that is holding the negative battery cable down to the floor of the trunk… I wouldn’t take that cable off the post, but will it mess up the car if I remove that hold-down nut to put the negative eyelet on that ground bolt? I’m not usually this tentative but with the massive amounts of electronics on this car, that AGM battery and its peccadillos, I don’t want to risk damaging or compromising anything. Is it ‘safe’ to take that nut off?

OK, so again, inspired by RoadKill, went out to put the CTek tender negative eyelet on. I’m usually cautious, but even more so with this whole concept of AGM. Not interested in messing up the electronics or frying the car. Consulted electrical engineer friend who advised having assistance to hold down the negative cable while I took off the negative cable nut, put on the eyelet, stainless lockwasher and then replaced the nut. All went well. Connected the Ctek, set it for ‘standard battery’ and AGM and let it sit. This battery was replaced end of October by the dealer, not sure how much of a charge it had in it when it went in. I’ve read elsewhere that they may just pull a battery off the shelf, do a minor check and stuff it in. Photos are of the positive connection (where I tapped the open, left side of the battery T bar), and then the ‘floor’ connection for the negative ground.

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Your connections should be fine, negative to the body or negative battery terminal the same result. Nothing special about the AGM battery except it is recommended not to let it run down completely. I did run my Optima AGM completely flat when my alternator went out on my E type. I am on my 2nd Optima, the first one was replaced after 13 years of use and was still strong. Only replaced it because I was going on a 4K mile trip and did not want to chance it. I don’t believe the F type will let the battery run completely down before it shuts it down. Example if battery is too low the stop/start feature is disabled, darn I hate that stop/start. The earlier F type had a small 2nd battery just for stop/start.