I want to play the sound from a portable sat nav unit through my car audio system?
Answers:
It is possible yes. By somehow transmitting it over the fm frequency with an adaptor. Or if the radio has an input use the headphone socket on the side of the unit. And another (it was on a C2) had an add on to the wiring loom. It cost about £18 and £40 to fit but did exactly as you want.
if it has a headphone jack, you can play it with a FM transmitter available in any electronics dept or store :)
The Nuvi 310 has an external headphone jack, you can use this along with an FM modulator to transfer the sound to your stereo using certain FM channels (depending on which modulator you buy). Generally they run between 30-80, I've found that the I-Rock brand works great for a reasonable price. You should be able to find a modulator at just about every electronic store and even online. Hope this helps.
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