I recently bought a InV SV2 sirius satellite reciever and i would like to hard wire it into my TC, the cigarrete adapter it came with reduces the voltage from 9-16V to 5V which is what the unit needs for power, so my question is how would i go about wiring this into 12V DC? can i just use some resistors to reduce the voltage or what? i have a ton different size resistors here but i was worried about heat being a issue with resistors, esp since the wiring will all be tucked up into the headliner where i will be tapping into for power.

thanks for you help, chris

 

They dont have a straight, 12V power cable?? Does the cig adaptor actually contain the regulator? So if you plug it in and test the voltage at the other end (where it connects to the unit) is it 5V?

If nothing is truly available, and the unit truly takes 5V coming in, it is pretty easy to build a regulator circuit if the current draw is known.

 

wire it w/ your cig lighter because its already tied in w/ the ignition.

 

You could mount the adapter under the center console, solder some wires to the contacts, tap into the cig-lighter, then run your 5V out of the adapter up to the unit.

If you want to tap the 12V from the map lights/moon-roof controls, then you’ll need to use a regulator to get your 5V. Assuming that the radio is probably using far less than 1 amp, you could get by with a simple 5V regulator (LM7805) and a couple of capacitors. If you’re not sure of the current draw, you could also just gut the adapter for the circuit you need and assemble it in a slim package to fit underneath the headliner.

 

you can use the cig adapter that they gave you just solder your power wire to the tip on the top and your ground to the sheild on the side then wrap it with elec. tape and tuck it away and we always get our power behind the head unit.

 

you can go to like autozone or walmart and buy a cigarette lighter outlet and wire it up behind the dash and use the adapter supplied

 

I bought the Sirius Sportster 4 several months back and had this same issue. The cigarette adapter has a regulator built in. I disassembled the adapter and soldered some short wires to the positive and negative terminals. Then, I used a couple of T-taps to tap into the cigarette lighter wiring inside the center console. I used some double stick tape to keep the modified adapter from rattling around inside the center console and haven't had any problems with it.

 

thanks for the responces guys, i think im gonna just crack the lighter open and use the existing circuitry, and yes the unit only uses 5V theres a regulator in the adapter which reduces the voltage before entering the unit, i think they did it this was to keep the unit small and compact.

 

just use the power off the same line as the cig lighter - its no harder then that.

 

Are you suggesting just snipping off the adapter and splicing the wires directly to 12V? It works for some accessories (lights, radar detectors, etc.) that use a direct 12V, but in this case he needs 5V to supply the unit since the regulator is located inside the adapter.

 

x2 this would be the easiest way to do it and it will be easy to reverse it too if need be.

 

I forget which one I had but i think it was called the sportster or something ....and i wired it right into the 12v - i have no clue (i dont remember) how much it needed.

 

The older version of the Sportster was 12 volt if I remember correctly. The new one (Sportster 4) needs 5 volts. I didn't realize that when I first wired it up and tapped directly into the 12 volt power wires. The Sportster wouldn't turn on at all. It needs 5 volts going into it.

 

^ no kidding - jeze - whopz!! Sorry for my mistake then.