Battery disconnect question

I have a question about disconnecting the battery (I'll be taking out the drivers seat to install a fire extinguisher mount) which I can't seem to find an answer to with a search. In shor, do the radio and other electronic settings remain in memory for some time after the battery is disconnected or are they immediately lost? My primary concern is losing the setting on the radio which allows the OE iPod interface (the direct-wire FM modulator) I had installed to function. It would be nice if I didn't have to make a trip to the service department... I'm thinking the battery disconnect is a far safer way to go than perhaps pulling the fuse (is there one?) which controls the airbags? Thanks for any help!

The times I've disconnected or replaced the battery, the radio pre-sets have remained. BTW, I took out the driver's seat to install the Rennline extinguisher mount, and did not disconnect the battery, and did not get any errors or any other problems. brad

Thanks Brad. I'm installing the Rennline bracket as well. I've always read disconnecting the battery was a must-do so the airbags can't accidentally be set off. Apparently you don't feel that way? Also, if you don't mind - the install article here says the bolts holding the seat down should not be re-used. I can't think of any reason for this other than a liabilty issue on the part of Porsche. I was planning on re-using the bolts. Do you see any problem with this approach?

Not re-using the bolts is a new one on me - I've not heard of that... it's not like they're "stretch" bolts or anything... I reused them, and have had no problems. After a week or so, I'd recommend testing their tightness again... I did, and they were still just as tight. I don't remember the torque value for them, though. The toughest part of the bracket install was actually wrestling the seat out of the car - it seemed to go back in more easily - and getting the holes of the bracket lined up with the existing holes in the metal seat bottom... I saw that it was easy to unhook the springs from one side, so that helped things along. Edit: Oh, and test fit the extinguisher on the bracket before putting the extinguisher holder onto the bracket - the extinguisher (probably depends on which one you have) should not be exactly centered - it will get in the way of the seat adjustment handle if it's centered... brad

+1 on the above comments. I would also put a folded towel or blanket down before you remove the seat to prevent scratching the car. The OEM seats are heavy.

The seat rail bolts are 37 ft-lbs. I seem to recall seeing a recommendation not to reuse them also, but I don't think too many people follow that. I didn't disconnect the battery when I installed my Rennline bracket, but the radio will remember your presets if you do disconnect it. BTW, I did do an Article on installing the Rennline Bracket here: Fire Extinguisher Mount - Comparison with Other Mounts - My Articles (though it might not have answered your specific questions).

Thank you for the information. I read your article, and it's primarily what led me to the Rennline bracket! Now here's to hoping the parts show up today so I can have a weekend project!

For the record, I disconnected my battery to intall the fire extinguisher bracket and did not lose any radio presets or my iPod connection. :banana: I did have to reset the clock, and pray the the PSM and PASM failure warning would go away, but they did so all is well! The installation was fairly straight-forward and I didn't seem to mess anything up. Getting the seat back in seemed to be much easier than getting it out for some reason. My only issue is the bracket which came with the extinguisher does not match up with any of the holes on the Rennline bracket. I've got something rigged for now, but I'm going to have to make a template and drill some holes, I guess. Otherwise I'm very pleased with the result!

I did not disconnect the battery, either, and actually, did not have to remove the seat completely from the car to complete the bracket install (I was attempting to remove the seat but decided that it just wasn't worth the trouble). After placing towels over both the center console and the doorsill, I removed the seat bolts and then tipped the seat back and towards the passenger side of the car. I disconnected the electrical cable under the seat, and would still recommend this step in the outside chance that tools banging, errant contact during bracket installation, etc, would cause an issue. I was able to install the bracket with the seat in the car, although I did have to work with the installation instructions held upside down. Total work time was less than an hour. It should be noted that the extinguisher is obtrusive for everyday driving; however, the actual extinguisher housing, as well as the extinguisher, can be removed from the mounting bracket and then reinstalled for events where required (I installed mine for SORC in Nebraska). I know that many feel an extinguisher to be an important safety accessory for our everyday roads, but I've never had the occassion to use one and in the event of use, would likely end up as I do following labor day grill duty, sans eyebrows.

I installed a SpeedTactics mount a year ago (purchased at Cayman Club auction). It does not require seat removal. It does limit the forward movement of the seat a little(I have GT3 seats). This would only be a problem if you need the seat all the way forward. It was an easy install, it looks good and is functional.

I tried the SpeedTactics mount previously, and found because of my seating position (relatively forward) I could not fit the extinguisher under the seat. The SpeedTactics piece is well made and very easy to install. I guess I need to put mine up for sale in the classifieds...

Regarding the battery disconnect when pulling out the seats... The key thing you must avoid is turning on the ignition switch while the seats are disconnected from their electrical harness. This will cause error codes related to the airbags within the seats and the seat belt tensioners. Clearing those codes would likely require a trip to the dealer or using a Durametrics unit. I left my battery connected when I did my extinguisher mount, but put a big piece of blue painters masking tape across the ignition switch with "NO!!!" written on it. I figured that would stop me from forgetting and putting the key in while I had the seat out. Doug