Just got a new stereo for the car, but it won't store any radio stations. The previous one didn't either so I'm thinking that it's not being supplied power to store the stations in the memory while the ignition is off. It's a saab if that makes any difference. Anyone know what i should check? I have an electrical multimeter.
there should be a permanent power supply that is on if the ignition is off and a switched one as well, the permanent one needs to be the main power for the stereo
If you do a Google for radio ISO wiring you will find some good explanations.
Basically the radio has a 12v permanent feed to power it and also retain presets/clock etc, then there is a second switched 12v feed which just tells the radio when you've turned the ignition off. Sounds like someone has messed with the wiring and both feeds are switched, or maybe your main 12v feed has blown a fuse and the radio is able to draw its power through the switched lead. (unlikely as its not usually fused high enough to be used to power the radio)
Or, like me, you have a Fiat, where they decided to integrate the CANBUS system into the radio and changed the standard pins, so botchery is required to get a non Fiat radio to work.
I thought as much. I bought the car from AUTOCLICK in Bristol who are a bunch of total w@nkers. Stay away!
It's easy to do:
1.Identify which input on the radio should be permanently live ( from the instruction book ). With the multimeter determine which wire is live when the ignition is off.
2. Introduce one to the other.
3. Drink a nice big mug of tea
Sony radios often need the permanent and ignition 12V feeds reversed before they work properly. I assume others are similar.
As others have said, use your multimeter to identify the permanent and live wires and swap them. There's a good chance that they'll be the only two which you can swap without tools anyway.
Some radios have a cable/terminal for memory!
If you find this, then use a multimeter or a 12volt tester to identify the live feed with no key in the ignition and bingo-hope it works.
Also your car could have a pixie that deletes the settings at night...
Ignition and battery lives the wrong way round. Ususally the red and the yellow wires in aftermarket radio leads.