Trying to open the hood with dead battery and dead key fob

I have a Porsche Boxster 2004. I followed the procedure to open the hood with an external battery; however the alarm goes off when I connect the battery. I tried to turn off the alarm by turning the key in the door lock, that didn't help. My remote key fob doesn't work. Any other ideas? Second question: can I buy a (used) key fob that's cheaper than buying one at Porsche dealer? Thanks

When the alarm goes off, please the key in the ignition and turn it to the "run" position. This will silence the alarm. At least it works in my 2002 C2.

Put your key in the ignition switch before hooking up the battery to pop the trunk. It reads the pill in the key fob there and won't set off the alarm. Second question - no. No matter what type of key fob you get it has to be programmed to the car immobilizer....by the Porsche dealer or an Indy with PIWIS.

Thanks for your suggestions. I did put the key in the ignition switch and turned it. But I suspect because my key fob is dead and the battery is dead at the same time, the alarm still goes off. I'm going to try again a couple of things.

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Key fob being "dead" won't affect your ignition, only the alarm/lock process. They key fob contains a non-powered transponder chip that completes the ignition pairing for start when the key is inserted. Make sure you have a good, strong "donor" battery for your fuse panel jump and that you have a good ground. Have you replaced the fob battery? Usually the fob will unlock the hood more ready than the inside switch. Good luck.

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Thanks a bunch for your response. I did replace the battery in my key fob, no success. The light on the fob doesn't flicker when I press the buttons on the fob. I opened the key fob, the switches on the circuit board don't seem to work any longer (no mechanical clicking). Also the circuit board seems to have some sticky substance on it. May be it melted. Could it be that the non-powered transponder chip is not working? Donor battery is good & have good ground. Unfortunately I don't have a second key, only a small spare key (but that won't do the pairing either I assume). Seems like my only recourse is to go to the dealer and get a new key, which I expect will cost me ~$500.

Good lord! Is your problem all about the key fob? I thought your car battery was dead and you were trying to get the trunk open. Open your door, insert your key in the ignition and turn to position 1, jump the fuse panel to open your trunk, ignore the alarm and get the trunk open so you can deal with the car battery. Your key fob is dead, as mine has been for umpteen years. It still works just have to do it manually from now on. Yes, the solder joints on the circuit board in the key fob go bad. But the key works just fine.

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Yes my primary problem is that my battery is dead and I can't open the trunk (front). I don't really care about the fob. I have been operating the key manually for a couple of years. The problem is that the side switch doesn't open the trunk following all the steps you suggested. I thought that was because the alarm seems to de-activate the trunk switch. It's just not opening the trunk. Is there another way to open the trunk (front)?

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Actually, right there is the problem boys and girls. Not trying to add insult to injury, but not smart driving around in a 996 with dead key fobs. Too many have learned the hard way with these cars. Your car may be immobilized which would mean it disables the ability to access the frunk and engine bay. You may have to go through the fender well and pull the manual frunk release cable. Good luck with that!

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So are you saying that there's no way to open the trunk (in a 2004 Porsche boxster) with a dead key fob and dead battery? Seems like a design flaw to me. Is there no mechanical way to open the trunk by possibly removing the front bumper? As a last resort I can be a new fob but that's going to cost me $500 or more?

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You'll need to access the manual frunk cable. See picture.

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Assuming he means the FOB battery is "dead" the key should still work the transponder pairing - no power need in FOB for that. The spare (valet) key has no battery and it works with the transponder. Since OP has the spare key, he should try that one. If it doesn't work then I'd agree the immobilizer is "dead".

Do you have access to a manual? Lookup opening the trunk when battery is dead. You car has a cable hidden under the bumper. It is accessible through the right wheel well after removing the liner.

And do yourself a huge favor - once you get the trunk open to replace your battery, relocate the emergency release cable to just behind the front tow hook plug so you don't have to go through all this again....like..can't remove wheel liner because I have to remove the wheel and my wheels have wheel locks and the socket for that is in the trunk. The emergency release cable is located underneath the passenger side light, which can only be removed if you have access to your trunk. Get my drift....?? Have you tried putting a battery tender charger on the cigarette lighter to see if you can get enough juice into the battery for things to work? Might be worth a try. Or, fish the emergency release cable out from under the drivers side rear light, open the engine lid and put a battery jump on the jumper points in the engine bay. Then try to open the trunk.

Thanks for your replies. I did manage to open the hood with the emergency wire, which is in Porsche Boxster (2003) model on the passenger side in the wheel well left of the head light (need to remove the liner).

Did the car start with the jumper/new battery?

I love a happy ending

Read through the whole thread but mine case is difference. My car is 2014 Cayenne GTS with regular key fob (not keyless go): - It worked until 2 days ago. - Suddenly it can't remote unlock and lock the doors from 4 feet away. - I replace key fob battery, - Tried both keys, both same issue. - But then I found out I can lock and unlock the car near B and C pillars (within 1 foot) So I think the receiver or receiver antenna has issue. Any suggestion?