12v Accessories ya know through cigarette lighter thing

[sutech]

I've been wanting to provide a way to keep power running to my PDA which also doubles as my GPS while on a ride. So I installed a 12v cigarette lighter power adapter on my FXST. Great fine and dandy. Now when I plug in the charging cable it lights up like it's charging but when the PDA is on it slowly uses more juice then it's getting and eventually the battery is drained on the PDA. I tested it in the car by taking a long trip and using it through the car power but it fully charged the PDA and kept it charged the whole time.

Now I don't know much about amps and volts and stuff. But does the little harley battery not put out as much power and stuff or could there be something wrong with my set up? I'm baffled.

Thanks!

I'm thinking that you're car probably has a power point that is hot all the time. The one on the bike is only hot when the ignition is on. That would be one thing.

If you've eliminated that, the other thing that comes to mind is that the charging system on the motorcycle is somewhat different than that of a car, in that it is running at a deficit at idle (using more power than it produces). This is true up to about 1800 RPM. If you're riding a lot in town, anytime the bike's draw is greater than the charging system output, not only is the PDA working off it's battery, the bike would try to draw power from the PDA's battery as well. It wouldn't take much of that for the PDA battery to discharge.

This is the same theory those solar battery rechargers, and the other "jump start" gadgets that plug into the cigarette lighter use. Think of the cigarette lighter not so much as a source of power, but as an access point to the electical system. Depending on the state of the system, power can either be put out, or taken in through that access point.

Harris

[sutech]

Well that just stinks. Anything that can be done about it? Carry a spare battery my only option? I'm trying to plan for a long road trip next summer. How do you other peeps with GPS or MP3 systems do it?

[ViennaHog]

Just hook up a voltage meter and see if you get =>13.5 Volts at the battery terminal when running the engine above 2000 rpm. If you are substantially lower, something could be wrong with your alternator/regulator circuit. If OK, check the voltage adapter of your PDA, may not work as advertised.
Other than that what Harris said

[2004-FLHRSI]

I think you'd want to take 'UNSWITCHED' battery rather than SWITCHED for your PDA (and other accessories) as long as they take minimal currents.

I run a GPS/APRS rig under my saddlebag lid. I also have a cell phone charger that I use at the same time. SEE LINK The electrical system keeps the GPS and transceiver running constantly. Current draw is about .15 amp at engine stop. I've never had the battery NOT be able to start the bike after sitting for days. Eventually though, all accessories CAN and WILL drain the battery. This includes the factory security system! That's why there's a procedure outlined in your owners manuals for disconnecting the battery and/or disabling the security system.

Also - SHOULD you ever discharge the battery to a point that it doesn't have what it takes to run your starter, disconnect your accessories and get a push start. If your alternator is working correctly it will bring your battery back to a charged state while your motor is running.

Good luck!

Matt

Originally Posted by ViennaHog

Just hook up a voltage meter and see if you get =>13.5 Volts at the battery terminal when running the engine above 2000 rpm. If you are substantially lower, something could be wrong with your alternator/regulator circuit. If OK, check the voltage adapter of your PDA, may not work as advertised.
Other than that what Harris said

[The_Snowman]

Originally Posted by sutech

I've been wanting to provide a way to keep power running to my PDA which also doubles as my GPS while on a ride. So I installed a 12v cigarette lighter power adapter on my FXST. Great fine and dandy. Now when I plug in the charging cable it lights up like it's charging but when the PDA is on it slowly uses more juice then it's getting and eventually the battery is drained on the PDA. I tested it in the car by taking a long trip and using it through the car power but it fully charged the PDA and kept it charged the whole time.

Now I don't know much about amps and volts and stuff. But does the little harley battery not put out as much power and stuff or could there be something wrong with my set up? I'm baffled.

Thanks!

sutech,
Any chance of getting an update on this issue? I am looking at doing the same thing with a Toshiba 750 PDA with GPS card. I find it hard to believe that a PDA could drain your battery; typically, they only draw 5 Volts at 500 Milli Amps.

Do you have a pictures or further information on how and where you connected the cigarette lighter power adapter? I have a FXST also.

Anybody else with suggestions welcome to respond also, not that I could stop you

[toybox99615]

I believe the starting place for this entire set of posting should begin with determining the power requirement of the GPS/PDA etc. Most of the units I've looked at draw a minimal amount of current (amps). Most draw about the same as the radio/cd unit on an Electra glide. And while the bike does only put of at engine rpm above 1,800 I would expect the bike should be able to supply adequate power to keep the PDA/PDA charged.

There are lots of other things (heated clothes, heated grips, etc.) that are powered through the accessory connector (the extra plug not the lighter). I see no indication on various wiring diagrams that the available current to the cigarette lighter is less than what is available at the accessory connector.

I agree with a previous poster the adaptor pluged into the lighter could also be at fault.

[toybox99615]

I believe the starting place for this entire set of posting should begin with determining the power requirement of the GPS/PDA etc. Most of the units I've looked at draw a minimal amount of current (amps). Most draw about the same as the radio/cd unit on an Electra glide. And while the bike does only put of at engine rpm above 1,800 I would expect the bike should be able to supply adequate power to keep the PDA/PDA charged.

There are lots of other things (heated clothes, heated grips, etc.) that are powered through the accessory connector (the extra plug not the lighter). I see no indication on various wiring diagrams that the available current to the cigarette lighter is less than what is available at the accessory connector.

I also agree with a previous poster the adaptor plugged into the lighter could also be at fault. So get a VOM and check the adapter output.

[sutech]

Originally Posted by The_Snowman

sutech,
Any chance of getting an update on this issue? I am looking at doing the same thing with a Toshiba 750 PDA with GPS card. I find it hard to believe that a PDA could drain your battery; typically, they only draw 5 Volts at 500 Milli Amps.

Do you have a pictures or further information on how and where you connected the cigarette lighter power adapter? I have a FXST also.

Anybody else with suggestions welcome to respond also, not that I could stop you

So I finally got back to this as I was installing some more crap I bought.

First thing, looks like people got confused on what was happening. It was the PDA battery that was draining, not the motorcycle battery.

2004-FLHRSI was absolutely right. I had originally hooked up one of those deutsch connectors to the little accessory connection under the seat so I could make sure the socket stayed off when the bike was off. I picked up a volt meter and turns out that was only pumping out about 8-9 volts down there.

I switched and went the old route of standard straight positive/negative connection to the battery (UNSWITCHED) with a 12amp fuse and tested it again. 12-13 volt with the bike off. Plugged the PDA in and the charging light when on. I wish I could keep it off when the bike is off, but so long as I keep the weather cover on, it should be fine.

Snowman, if you are looking for directions I went to Autozone and bought a 12v outlet that was weather sealed. Made for boats and trucks and stuff. I mounted it at the bottom of one of those leather tank panels with the pocket that harley sells. Positive goes to a 10amp fuse then to the battery, negative goes to the ground screw on the frame.

[The_Snowman]

Originally Posted by sutech

Snowman, if you are looking for directions I went to Autozone and bought a 12v outlet that was weather sealed. Made for boats and trucks and stuff. I mounted it at the bottom of one of those leather tank panels with the pocket that harley sells. Positive goes to a 10amp fuse then to the battery, negative goes to the ground screw on the frame.

sutech,
Thanks for the lead on that 12v outlet, no AutoZone over here but going to Australia soon for a break. Great idea for mounting it also; I had my DFO stuffed in there, but now that I have a SERT I will be able to use it as you suggested.
Regards, John