My FM stopped working a while ago and I've since unpluggd the wire leading to the antenna (the one that goes up and down, not the rear-glass one) to prevent it from extending up from the car every time I listed to music via other sources. Can I draw a significant amount of current from the connector going to the antenna? I'd like to use it to power my (aftermarket) subwoofer amp and bluetooth adapter, can I do that? Is the fuse on that wire sufficient for a 1500w amp? (claimed rating, reviews say it outputs around 300w in reality.)

The amp & BT-adapter is presently being powered from the auxiliary connector in the trunk (the mystery plug that was originally used to charge the car battery on the ship during delivery from UK to the US) but this means that the amp is always on when the car is on, regardless of the radio being on - I'd like to have a switched source controlled by the radio - this would also allow me to reset the bluetooth adapter by shutting the radio and turning it back on.

 

The antenna wire is perfect to use for the 'remote on' signal to your amp, but it is in no way powerful enough to use as the actual positive feed to the amp. Also, the battery and factory fuse box are right there... just run a new, fused power cable, it's pretty simple.

The antenna feed should be enough to run the BT adaptor too, only possible issue is a delay when you turn the car on, but I doubt it will be an issue

 

Thanks - I assume the power remains on while the radio is on, right? This is not just an intermittent signal for the antenna to rise, right?

 

Yes. I'm using the same feed for my amps

 

The mystery aux connector has a switched power line. The grey/purple wire (if I remember) becomes a switched line once you plug in a relay in the fuse box.
It's described in greater detail here: https://www.jaguarforums.com/forum/x...t-boot-152821/

Of course the radio doesn't control it, it's just on when aux power is on.

 

Yup, I've added the relay and am using that now, but would like to be able to shut off the amp from inside the car

 

Anyone know what each of the power wires to the antenna do? Black is presumably ground, but there is a green and a brown with green stripe. If I had to guess what jaguar was engineering, I'd say one is switched to the radio and the other is unswitched so the antenna can have power to retract after the vehicle is shut off, but I'm just guessing.

 

Wiring diagrams are all here
JagRepair.com - Jaguar Repair Information Resource

 

Thanks, after much decryption, green-black wire is switched, comes from head unit after passing through 2 resistors. Brown-green wire is unswitched and comes directly from the fuse box.