Battery dead - can't open hood
 

I have tried searching for an answer to my problem without success, so perhaps someone can put me on the right track.

My car is a 2010 Boxster S and today when I went to start it after it had been parked up for about three weeks, the battery was dead. I thought that I knew how to deal with this, but clearly I don't.

I unlocked the car with the key and popped the lid on the fuse box. I pulled out he red tab and connected another battery with the positive terminal connected to the red tab and negative to the chassis of the car. I can hear a relay click when I do this, but no matter what i do, I am unable to get the hood release to work. It is completely dead.

What am I missing here please?
My reading suggests that the cable hidden behind the plastic shroud in earlier models of the Boxster is not available on mine. Is that correct?

Thanks

What you've described is the proper procedure and it works.

Check the charge on your spare battery.

Re-check the connections and hold the frunk button for 5 or 10 seconds.

On the 981 cars, there is an emergency release cable above the driver's side wheel well liner, towards the front, up against the inward side of the wheel well. It's a thin stainless steel cable about 1 mm in diameter. you have to remove the wheel well lliner, or at least release the forward/top part of it to get to the cable. I think it is in the owner's manual. If this doesn't apply to 987 cars, disregard.

The ignition was left on in my '16 CS (wife claims innocence) so battery was 100% dead. Even after hooking another battery up, it took a while until things began to work. I assume the car's battery was depleting the voltage from the supplemental battery until it had come up to a minimum level. So, just giving it a few hours might do the trick.
Bern

Many thanks for the advice. I will try leaving the supplementary battery connected for a few hours in order to try to breathe some life into the car battery which appears to be totally exhausted.

This issue is now resolved thanks to the assistance here and in particular, bernb6 who set me on the right path.

For the benefit of others who might face this challenge, here is how it was resolved.
The battery was heavily discharged if not completely discharged. I pulled a source vehicle alongside and connected jumper leads - positive to the red tag in the fuse box and negative to the door striker. I then placed my battery charger on the source vehicle's battery and left everything for a couple of hours. On my return, pressing the remote release button on the key released the lid. Note that at this point, the release tab in the sill would still not operate the latch.

It seems that the discharged Boxster battery was holding the supply voltage down to the point that the remote wouldn't work. Once I got some charge into the Boxster battery the system described in the manual worked.

Hi all, I'm a new Vendor on this forum and my company is Antigravity Batteries. We do the Lightweight Lithium-Ion Batteries you might have read about.... So I wanted to lend my personal experience to this. I JUST bought a GT3 RS on Wednesday super stoked). So we are making a Lightweight Lithium Battery kit for the 991.1 so I was working on replacing the stock Lead/Acid battery with the Antigravity Lithium Battery just this morning... So I made sure to keep the car energized with a side battery I had connected to the terminals so I wouldn't lose any settings and keep power to the car while I took out the original lead/acid and mounted the new Lithium battery.... ( I could have just connected the ODB2 connector to keep it powered but was not at our shop) so I get the install completely done, remove my detach the spare battery I was using to keep the car live before I switched batteries.... then close the hood so I can start the RS and pull it outside.

I get in the car put the key and and nothing...and the now key won't come out of the ignition and I'm ****ting myself thinking how can I be a battery guy screw this up so bad on a 4 day old, extremely expensive car... talk about your stomach sinking and a bit of panic setting in.... So I actually had to search Renn-List to find out how to get access to the battery I had just put in. Anyway I followed the procedure of pulling out the RED Buss in the Fuse box and then I connected postive there and neg to a chassis ground, I used the seat bolt since I knew that had to be grounded to the frame.... and immediately I heard the electronics click on and pressed the button and it worked to open the Trunk. Now my point of this is that you indeed need to have a battery with a good solid 12v, and you have to have a good ground as I found. I used the Seat Bolt but also the Door lock latch that the door grabs onto is a good ground since it isn't painted and has a solid ground to the chassis.

But I also want to point out another thing.... the new Lithium Battery I put in the car was OFF.... meaning NO VOLTAGE at all. That was my big mistake, our batteries can be turned OFF or ON. So I thought I had changed out the battery and was ready to go but I forgot to turn the Battery ON. So I had absolutely nothing in terms of voltage to the car, nor would it have worked to try charging the battery through the Cig Lighter because the battery would have still been OFF and not accepting a charge. So this led me to find (after more testing) that you have a solid 12v source capable of about 15 Amps so you can fully energize the system enough to pop the Trunk... you actually don't need a Car Battery just a solid 12v/ 10 to 15 amp source to get the system active. I just used a product that we make that is a mini jump starter called a MICRO-START... but what I did learn on doing some testing was that is has to be a solid 12v minimum that is putting capable of 10-15 Amps of current for the system to really engage...

So in the end I just turned on our Lithium Battery and all was good... But the cool thing about this new Lithium Battery we make is it has something to the effect of BUILT-IN Jump Starting so the the fact is you NEVER can be stranded. For example if you left you Ignition on... (like someone wife above did accidentally) this battery actually intelligently monitors its voltage... then puts itself to sleep BEFORE it is completely dead. It save just enough energy to RE-START the vehicle... and once started you can drive away and re-charge it. So that is our new ground-breaking technology.... figured my scenario and you examples were prime reasons to get you a little data on what we do. If you ever have battery questions PM me.

You can see what this new battery is here in case you were interested. https://shop.antigravitybatteries.com/products/starter-batteries/automotive/rs-30/

Yes please PM me with any questions, it was not my wish to intrude on this thread with our battery as the focus, but I did want to post about this newer technology being available. I will also be starting a new Lithium Battery thread in the different categories... but I was hoping to be a little closer to being finished with our drop in mounting system for Porsches. But just PM me and within a few days I will have a thread that answer everything. Or you can email me at scott@antigravitybatteries.com...

PM'ing you Marine...

I bought a Lithium Jump Starter that came with two large scissor clamps I can hook to the fuse box emergency power prongs. This will provide external portable power to open Front and rear trunk after door has been opened w/ emergency key. I keep this behind the seat cubby hole storage box.

https://www.costco.com/Lithium-Jump-...100312116.html