Solar Powered P5 !!!

pcb

The Diagram Dude
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2002 MP5
Well not really powered but it should help with winter starts and keeping the battery topped up.
I had to remove the plastic moldings on the solar panel so it would be thin enough to fit under the bracket above the sun shield. I had to remove the glass of the sun roof to feed the wire around the sun shield.
I routed the wire over then under the sun shield to the interior light where there is a constant 12 V so it will charge with the key removed.
The solar panel has a diode so it won't discharge the battery in the dark. I may install another diode at the interior light in case the sliding panel cuts through the wire. (it's just kinda draped in there loosely)

Maybe somebody can copy my idea and do a better install and post a how to so I can copy that. My install is pretty cheesy.

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Looks awesome!

Is your setup designed to run the A/C when the cars not running? Or are you using this with the alternator to run your electronics?
 
No,... It's only a 7 watt solar panel with full sunlight,... I'm thinking I can feel more comfortable having the radio on or operating the power windows with the car off. I did the power window always on mod so now that little 'auto' light on the power window button is always on. It's only about 20 mA but it bugs me.
I think it might help with the occasional squeal from the alternator when I start up the car.

I had a few very slow starts last winter after the car had sat for a few days,... I'm thinking this should help keep the battery fully charged and maybe even create a bit of heat in the battery to help it along in the winter. (my uncle used to take his battery indoors on really cold winter days to warm it up so he could crank over his engine)
 
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The little light in the window would take well over a year to drain the battery. With a cheap dura last battery you can run the stereo for about 2 hours before it drains the battery enough to not start( this was with a 600 watt amp with 2 12s) if it squeals when you start it up then adjust the belt. The only way to not have a hard start in the cold is a better battery

Not trying to be a dick, I think it's pretty cool just kinda pointless. But I'd like to be proven wrong on it not helping with cold starts in the winter
 
I had a battery that would crank really slowly after being parked for a week. Newegg had a 2-for-1 sale on these solar chargers so I grabbed a pair. The car didn't crank slow anymore even after a month of sitting as if I had bought a new battery. So yes they work if your battery is just slowly draining. It will not run the radio or anything useful on its own, let you keep your lights on by mistake all day, or charge a completely dead battery. It's a battery maintainer and a marginal one at that. If you're killing your battery by running the radio for a bit or just using the power windows you need a new battery.
 
I'm kinda OCD about power use in my car,... I like to keep my power drain as small as possible,... I figure it extends the life of my battery and alternator.

I keep in mind the 80 amp max of my alternator and try to use high drain items one at a time. I turn off my blower when I turn on my rear defogger. I open one window at a time (it even says to never open more than two at a time in the manual or you'll blow a fuse). I don't like going over 80 amps because then I know I'm draining out of the battery as well as maxing out the alt.
My battery is at least 5 years old now and still running strong but I'm sure if I did frequent engine off power drains I would have had to replace it by now. I fill it up with distilled water every year and now that I put in the solar panel I actually ran my radio for 45 minutes today with the engine off. I wouldn't have done that otherwise.

I think of it as a permanently installed trickle charger,... It was only 10 bucks on sale and I don't think there is any drawbacks except for my shity looking install. (but it's not too visible under the sunroof).
 
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I decided to service my battery.

Not that there was anything wrong with it, lol.



The fluid level was pretty good. It just needed a bit of water.





I cleaned up the battery terminal and put it back on.
(forgetting that I reset the ECU. Now it's gonna run like crap for 100 miles)



I sprayed down the terminals with rust proofing and put it back together.



I'm sure my little solar panel has a lot to do with the life of my battery.
My car always strarts even when it's -20 C.




The battery is more than 11 years old.



I have these to put on but the original straps are are still in pretty good condition.

 
No,... It's only a 7 watt solar panel with full sunlight,... I'm thinking I can feel more comfortable having the radio on or operating the power windows with the car off. I did the power window always on mod so now that little 'auto' light on the power window button is always on. It's only about 20 mA but it bugs me.
I think it might help with the occasional squeal from the alternator when I start up the car.

I had a few very slow starts last winter after the car had sat for a few days,... I'm thinking this should help keep the battery fully charged and maybe even create a bit of heat in the battery to help it along in the winter. (my uncle used to take his battery indoors on really cold winter days to warm it up so he could crank over his engine)
Mine's a garage ornament without a sunroof so I alls I got is the battery tender thing option.........
 
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