Prairiedawg

I screwed up and left my keys in the ignition last night and found the battery dead when I got home from work. Fortunately I have spent enough time here on RL to know to use the key fob to open the frunk (its not a total time waster). Luckily there was enough juice to pop it.

My question is, will my Ctek be able to recharge the battery alone? I had it on the charger but with the key in, it must have pulled more than the charger could give. I only knew there was a problem because the red caution light was on the charger.

I probably need a new battery soon, I've seen some weird faults in the past- subtle clues. It would be nice to get it started if I have to take it somewhere.

Also, does it make any sense to move up to an AGM battery? This is for a 997.2 GTS

Thanks guys

CAVU

I do not think the key caused a battery discharge as you have described. I suspect a battery near the end of its effective life. I would rest the charging cycle... Ctek red light might be telling you to unplug it, disconnect it from the battery, reconnect it back to the battery double checking matched terminals, plug back in and set it back to charging. They are sensitive to power interrupts and over draw.

If the battery is significantly discharged, and your Ctek is a maintainer type, you will need to have the battery recharged with a higher amp charger.

What is the date code, type and make of your battery?

I went with an Odyssey AGM and have no regrets so far, but have AGMs now in all my vehicles. https://rennlist.com/forums/997-foru...yssey-94r.html

Prairiedawg

I did unplug it and it reset. I put it on recondition and I don't think it's charging. At this point I bought a new AGM battery but I'm wondering if it has to be coded by PIWIS or something. Did you have to code yours? looks like a 997.2 on your Avatar.

If I have to code it at a dealer or somewhere else, I'll just return it and go with lead acid. Otherwise the cost of the battery more than doubled.

CAVU

Might take it off reconditioning mode and put it back into charging mode.

No PIWIS is required. Just do not want the key int he ignition during the battery swap. Jumper the good battery to the bad battery and then take the key out. Disconnect and perform the battery swap.

Your owners manual has a fey steps after the battery swap to rest the windows, steering angles and TPMs...maybe a couple of other small things.

Prairiedawg

Good information. I got the key out already. I pulled the battery from my tractor and jumped it with that. Got the key out and was able to use the fob to pop the frunk. The drivers side window somehow lowered to get the door open but raised after that and I couldn't close the door. The tractor battery with jumper cables gave me enough juice to lower it so I could close the door.

I looks like a dead battery causes a whole host of faults to sort through when I change it. I'll probably leave it on the Ctek until this weekend and change the battery then. I went to Costco expecting to order an battery, didn't expect them to have it in stock. maybe it will charge enough to start and run. Then I can position it under my electric hoist to remove it the lazy way.

I'm happy to hear no coding needed to make the switch to an AGM.

CAVU

our cars have so many more modules (really computers) than in years past. They do not like unstable voltage and will let you know it with weird inconsistent faults.

Standard R&R of the battery is to stand in the frunk, and a helper to take the battery off your hands and to hand the new one to you. All easy. if you can get it running with the current battery, will costco charge you to swap it out?

Prairiedawg

I probably won't have a helper but I have an electric winch I can use if the hood opens far enough. I haven't looked closely enough, I'll manage one way or another. Costco is good and all but i'm not sure I would trust them.

I think the battery was on it's way out before today anyways. I was starting to get weird faults with the windows and convertible top, especially right after starting the car. After it ran a few minutes it was fine but I know enough that battery issues cause all kinds of weird things, so changing it was on my list of things to do before the end of fall.

Edit, the hoist from the ceiling isn't going to work. Have to find a plan B

Petza914

I just get in the frunk and lift it out. It's just a battery. If you can remove a rear wheel you should be able to lift a battery out of the compartment.

I only use AGM batteries. My next battery in the 997s will be the new Optima Yellow top H6. Currently I have red top 34Rs or R34s in them.

Wayne Smith

With shelter in place I've been swapping my battery tender between vehicles. At one point (my screw up) one of the batteries fully discharged to below 6 volts. My tender then determined it must be charging a 6 volt battery and as such would not charge the 12 volt battery back up. So I used my trickle charger overnight and once the battery was well over 6 volts the tender could take over again.

These batteries aren't that heavy. Stand in the frunk when removing and installing. You'll be fine.

With a dead battery the windows simply get weird. Other things may get strange as well. Once you get a good battery in the car you will probably need to reset the windows. Hold the down button until they are fully open. Hold the up button until they are fully closed. This will set the limits. You may have some warnings on the dash. Drive around the block and these will clear.

LexVan

Hey Dawg, this has NEVER happened to me. How embarrassing.

Prairiedawg

It wasn't embarrassing......til now🙄

Antigravity

This might be an option that will make it so you will never be locked out of your frunk , or stranded by a dead battery again...

Prairiedawg

Problem solved, thanks for all your help and input guys. I simply, replaced the battery. I overthought it all. Just like Petza said, climb in and pull it out.

I put a sheet down inside the frunk and between the battery and the front wall to keep from scratching anything. Disconnect the battery and lift out. Set it down between my feet in the frunk and climb out. Removed from the frunk and then reverse the process, no big deal. Didn't seem to have any issues with the car. I didn't drive it but the tpms was still there and the windows seemed to be fine. Got psm fault but I assume that will go away. Just have to set the clock and figure out if there's anything else missed.

Thanks everyone

Petza914

The PSM fault will go away almost immediately once you drive it.

Prairiedawg

Yeah, I figured as much.

Stupid mistake, I'll remember that one. Fortunately got away with though my wallet is lighter 1 battery.