cigarette lighter port always on..? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

ehD · 02-28-2007, 09:53 PM

my passport 8500 never seems to turn off in my car even if the key has been out of the ignition for a while... is this going to kill the battery? is there anyway for it to turn off automatically when the car stops?

986 Girl · 03-01-2007, 05:09 AM

I believe (but I could be wrong!) that this is a German thing, as it does it in all the e30's I've been in as well.

Hardwire the detector to one of the accessories that only turns on once the car is on. Other than that, or turning the detector on/off manually by hand when you turn the car on/off, I don't know of another solution.

Edit: Unless you were to leave the car off, with the detector on for probably a month or longer, I highly doubt it will drain your battery. However, I would not use that as an excuse to leave it on.

RandallNeighbour · 03-01-2007, 06:23 AM

I have given this issue some thought. My conclusion is that German automotive engineers like to go out to their cars during the work day for a smoke and don't want to put the key in the ignition to light a cigarette. It's a matter of efficiency to them I guess.

That's the only reason I can come up with as to why German cars always have an unswitched cigarette lighter.

djomlas · 03-01-2007, 08:50 AM

canadian models dont have this. in US models the power is there all the time.

porsche986spyder · 03-01-2007, 09:00 AM

Yes, there is not way around it. I just unplug my detector everytime I get out of my car. If you forget, it should not kill your battery. But if you left it pluged in, eventually it would start to drain your battery. Radar and laser detectors don't really draw a whole lot of amps. Just unplug it when not in use.

03-01-2007, 09:11 AM

My BMW also had this, I ran a toggle switch from the ignition to the dash so I could turn the car on or off with a switch without the key being put in. I have no idea how I did it, I originally put a switch inline with the power of the cigarette lighter. But after I added another cig lighter inside the dash, and added another switch for my iPod I could turn the acc on. It was great, I didnt need the key to put the top up or down, I just flipped a switch.

MNBoxster · 03-01-2007, 09:49 AM

Hi,

Most cigarette lighters are on-demand appliances built to DIN standard in which on-demand appliances are B+ (Battery Positive or constant Hot).

DIN is an abbreviation for the Deutsches Institut für Normung e. V, an institution of trade and industry responsible for the preparation of National Standards in Germany, similar to our own ANSI - American National Standards Institute. Since DIN had already created an electrical wiring standard, ANSI (as well as many other countries' standards committess) simply adopted it.

Early in the Industrial Age, it was determined that adopting a set of standards would insure consistency and interchangability in the design and manufacture of components from one supplier to another. Additionally, it allowed educators to ensure they were teaching standardized techniques in engineering and science disciplines to insure a consistent follow-on workforce for Industry.

These standards included everything from Pipe and Tubing standards, Screw, Bolt Thread size and pitch standards, to electrical connectors, packaging sizes for appliances (such as Din sized Radios) etc. There is even a DIN standard for electrical wiring. As such, a Car Manufacturer knew exactly how large a Radio would be from a supplier and could design the dash to readily accept it, etc.

In the electrical wiring DIN standard, it was decided to wire all on-demand appliances (such as cigarette lighters, door operated interior lights, etc.) to B+ (constant Hot), as having to energize all other electrical components (such as the ignition, fuel pump, Relays, etc.) was inefficient. This is the reason most lighters are B+. Hope this helps...

Happy Motoring!... Jim'99

djomlas · 03-01-2007, 10:16 AM

great info Jim,
my friend has a 530i and his lighter's power turns off w the ignition form factory, of course its a german car, so hows that possible then if the design is originally from good ol' Deutschland?

MNBoxster · 03-01-2007, 01:11 PM

Quote:

Originally Posted by djomlas

great info Jim,
my friend has a 530i and his lighter's power turns off w the ignition form factory, of course its a german car, so hows that possible then if the design is originally from good ol' Deutschland?

Hi,

There is no requirement to adopt the DIN standard, and as I stated most car's lighters are Hot, but not all. I cannot speak to a particular anomoly, there could be many reasons such as alarm system requirements, etc.

But, more often than not, you'll find the lighter is B+ (constant Hot) for the reasons I've given...

Happy Motoring!... Jim'99