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Guys, I've been a member or other auto forums for years, so I feel pretty stupid writing this, but I haven't been able to find the answer in all of the threads I've looked at so far (and there are 100's - 1000's? - that I didn't get to), so if this has been posted ad nauseam in the past, I apologize in advance. Here goes...
OK, I have a 2009 997.2 C2 Cabriolet and the battery is dead. I have followed the instructions, pulled out the pole in the fuse box, grounded the alligator clips, etc. and nothing has worked. I first tried a NOCO smart charger and I kept getting an error when trying to use it - one thread mentioned that because the smart charger is looking to detect battery polarity and it finds none (because the fuse box pole is tying into the ECU for the trunk lid, not the battery), it doesn't discharge any power (I have no idea if this is accurate, but I can attest the brand new NOCO that I bought for this purpose did not work).
I then tried the Porsche genuine trickle charger hooked into the cigarette lighter. Again, it didn't work and I'm assuming for the same reason the NOCO didn't? Again, electrical issues are not my area of expertise.
So, lastly, I hooked up my 15 year old Sears Die Hard battery charger and plugged it into the wall socket. All I got was the red error light and again, it would not distribute a charge.
I'm at wits end here. How am I supposed to open the trunk? And can I also say, along with the absence of a manual oil dipstick, the Porsche engineers (and the executive that approved it) get a big ZERO on this one. Jeez. Open the trunk with a cable (that doesn't require wheel removal). Any help is greatly appreciated. Thank you very much.
Guys, I've been a member or other auto forums for years, so I feel pretty stupid writing this, but I haven't been able to find the answer in all of the threads I've looked at so far (and there are 100's - 1000's? - that I didn't get to), so if this has been posted ad nauseam in the past, I apologize in advance. Here goes...
OK, I have a 2009 997.2 C2 Cabriolet and the battery is dead. I have followed the instructions, pulled out the pole in the fuse box, grounded the alligator clips, etc. and nothing has worked. I first tried a NOCO smart charger and I kept getting an error when trying to use it - one thread mentioned that because the smart charger is looking to detect battery polarity and it finds none (because the fuse box pole is tying into the ECU for the trunk lid, not the battery), it doesn't discharge any power (I have no idea if this is accurate, but I can attest the brand new NOCO that I bought for this purpose did not work).
I then tried the Porsche genuine trickle charger hooked into the cigarette lighter. Again, it didn't work and I'm assuming for the same reason the NOCO didn't? Again, electrical issues are not my area of expertise.
So, lastly, I hooked up my 15 year old Sears Die Hard battery charger and plugged it into the wall socket. All I got was the red error light and again, it would not distribute a charge.
I'm at wits end here. How am I supposed to open the trunk? And can I also say, along with the absence of a manual oil dipstick, the Porsche engineers (and the executive that approved it) get a big ZERO on this one. Jeez. Open the trunk with a cable (that doesn't require wheel removal). Any help is greatly appreciated. Thank you very much.
With a regular power supply (9-12V battery or 12VDC from another source) attached to the red terminal in the fuse box and ground should work, IF you are opening the trunk with a key FOB (not the doorsill switch).
Maintainers may not work, so use a regular 12V DC source (or even try a fresh 9V battery).
Most modern battery chargers won't work. You need a true DC power supply. Make sure you have a solid ground. The brake pedal linkage works. And then you will need to use the key fob rather than the switch by the seat.
Then, look up threads on the frunk release cable. You can attach an extra cable on the lower half of the frunk latch lever and route it to behind the right fender light. If you ever need to open the frunk manually you can pop that light out with your fingers or a credit card, grab the wire, and pull to override the latch. I wrote this up here some time ago but since then there have been several videos made that do a better job ... Google is your friend. I've done several of these additions. For some reason the added cable pulls easily on some cars and requires major force on others. I don't have an answer as to why. When friends bring their cards back for work I'll try to find some time to come up with an answer as well as a solution to make all cables pull easily. If you find a method please post it.
After doing the frunk cable pull the motor lid cable out of the left taillight. There is a hard to see hole under the latch. Feed the cable through that hole. Then remove the license plate and its mounting bracket, pull the cable through the hole that the mounting bracket was covering, loop the spare cable and secure into a loop with a tie strap. Then put everything back together.
As for the oil level, these cars have a built in sump chamber and a wide shallow oil pan. Measuring the oil in the wide shallow oil pan would be very inaccurate. By heating the oil, pumping it into the chamber, and measuring it there while the motor is running ... the measurement is better. A compromise? Maybe. An engineering solution? Yes.
And that brings us back to the frunk release. If it was easy then anybody could open your frunk, looking for valuables. Porsche engineers were backed into a corner, stuck between security and simplicity.
Most modern battery chargers won't work. You need a true DC power supply. Make sure you have a solid ground. The brake pedal linkage works. And then you will need to use the key fob rather than the switch by the seat.
Then, look up threads on the frunk release cable. You can attach an extra cable on the lower half of the frunk latch lever and route it to behind the right fender light. If you ever need to open the frunk manually you can pop that light out with your fingers or a credit card, grab the wire, and pull to override the latch. I wrote this up here some time ago but since then there have been several videos made that do a better job ... Google is your friend. I've done several of these additions. For some reason the added cable pulls easily on some cars and requires major force on others. I don't have an answer as to why. When friends bring their cards back for work I'll try to find some time to come up with an answer as well as a solution to make all cables pull easily. If you find a method please post it.
After doing the frunk cable pull the motor lid cable out of the left taillight. There is a hard to see hole under the latch. Feed the cable through that hole. Then remove the license plate and its mounting bracket, pull the cable through the hole that the mounting bracket was covering, loop the spare cable and secure into a loop with a tie strap. Then put everything back together.
As for the oil level, these cars have a built in sump chamber and a wide shallow oil pan. Measuring the oil in the wide shallow oil pan would be very inaccurate. By heating the oil, pumping it into the chamber, and measuring it there while the motor is running ... the measurement is better. A compromise? Maybe. An engineering solution? Yes.
And that brings us back to the frunk release. If it was easy then anybody could open your frunk, looking for valuables. Porsche engineers were backed into a corner, stuck between security and simplicity.
Thank you for the insights. While I'm still a bit cranky about the inconvenience to the end user, at least I have some understanding of the "why" behind those items. As for the DC being applied, what would you suggest as an appropriate DC source? Just pull the battery from my daily driver SUV and hook up jumper cables? Is there a recommended device that can be carried with you in the car? Although the cable extension does sound interesting.
Thank you for the insights. While I'm still a bit cranky about the inconvenience to the end user, at least I have some understanding of the "why" behind those items. As for the DC being applied, what would you suggest as an appropriate DC source? Just pull the battery from my daily driver SUV and hook up jumper cables? Is there a recommended device that can be carried with you in the car? Although the cable extension does sound interesting.
A regular 12V car battery sure, but be very careful with contacts. You cannot short the battery. I would try first a fresh regular 9V battery... or a 12V power supply (wart) making sure you connect the correct polarity.
There is another failure besides the battery that we really should not ignore. The solenoid itself. We really do need a mechanical override. The cables should be mandatory IMHO.
You just need to connect a good battery to the fuse panel using jumper cables. This procedure is outlined in the owners manual. I just had to do it recently.
Echoing what others have said, best to follow all 8 steps in the owners manual exactly…
If that doesn’t work, then you may have a solenoid problem. But I assume you know the battery is dead for other reasons as well (e.g. car won’t start).
10-17-2022, 07:09 PM
Electrical Help please - 997.2
