I have a sti which i only get to use of the weekend and have found that the battery keeps going flat so my question is has anybody used the solar panels you can get to trickle charge the battery, if so did it work and is there any reason not to use them on the preza.

How old is the battery/car?

In my experience batteries in motors need replacing after 3-6 years depending on the motor, its use and where it 'lives'. You can use them for longer but I can't be @rsed with hassle considering the cheap cost. Yours might just be 'tired'?

It shouldn't go flat even if you only use it on a weekend unless you only do very few miles each time. Unless you have some other electrical problem ... altnator?

The easiest way to figure out if is a charging problem or battery problem is to stick a voltmeter across the battery terminals. Without the engine running the reading should be 12+ volts
With the engine running it should be charging - maybe 13+ volts. [Don't know the exact figures or what revs the charging voltage is highest but that isn't necessary for a quick check].

If the voltage rises when you run the engine then the charging system is probably OK. So if the battery still goes flat, and the static voltage is 12V or less then it's probablt the battery that is on the way out.

Mine is 4 years old and less than an hour of the radio on manages to flatten it.... I must get around to a new one this summer!

Dave

If you aren't too bothered about buying a genuine Subaru battery, you can get a replacement from Toyota dealers. Mine cost £48 for my 93 wrx. Cheaper than the £80-odd I was quoted elsewhere!