First let me say "Hi." I've been browsing the forums for a while looking for a potential answer to my questions. I'm an Amateur Radio operator and I'd like to install a Kenwood transceiver in the car. (think Police radio or CB) my problem is not so much finding power for it. I plan to pull directly off the battery. I need to find a switched power point so using a relay I can shut the power off to the radio. The last car I had was from 2002. There seems to have been a shift in electrical design since then. I've gone through the fuse boxes in the engine bay and the driver's side cabin panel. I can not find an accessory switched fuse in testing. For all I know having the door open while trying to test the fuse power is messing up the results. Course it might also be the push button start. I've never had a car with that system until this Fit. I contacted the dealership and asked them and the fuse they suggested is hot all the time. Help!

To summarize. I'm trying to find a point (preferably in the fuse blocks) I can use switched accessory power to control the power to the radio through a relay. The radio itself will be in the package tray in the back with a remote "head unit" in front. I would prefer to not have to dig into the console to find the connection I need.

 

Welcome. I would highly recommend not running transceivers off the Fit battery.

We've had reports here of people frying various electronic components by using relatively low-powered accessories: dash cam, hand-held vacuum, portable air compressor, etc.

I'm guessing that your transceiver sucks more juice than these examples, and that damage to internals could get quite costly.

Any reason you can't take a spare lead-acid battery along and run off that? That way, you don't risk your vehicle's internals at all.

 

I plan to run the radio itself off the battery. I'm wanting to install a relay to shut the power off to the radio when the car is off. Otherwise the radio will kill the battery. I don't necessarily drive the car every day. And if leaving a dome light on by accident will drain the battery, the radio certainly will.

All I'm looking for right now is a fuse that is switched power that is off when the car is off and comes on in accessory mode or if the car is running. In a perfect world, I would love to not have to tear the dash apart on a car that's barely a year old.

 

how about running off the cigarette lighter socket?

 

While possible, I don't know how difficult it would be to get into the socket to connect some additional wires. Because I still use both USBs and the sockets to charge stuff. It's still a case of I don't want to tear into the interior if I can avoid it. I'm hoping someone can lead me to a good fuse.

 

Well, I tried to pull the power off the 12v cigarette lighter plug and couldn't get the daughter pin to fit in the plug. I may have to bite the bullet and actually tap the wire.I should add that the voltages at the fuse box don't seem to follow the key/switch position.

 

Are you talking about a high-power HF radio or something like a few watt 2 meter band radio? I wouldn't run an HF transmitter off a small battery like in the Fit. It's easy to draw too much power.

 

It only has draws less than 13 amps even at high power and only needs 13.8 volts. What I've been trying to do is find a place that I can connect a relay to switched power that will control power to this radio. And it's why I'm connecting the radio to the battery with a relay to control that power

 

Think which equipment is powered only when the ignition is acc or on and check the owner's manual for the fuse list. If remember correctly, the cigarette lighter type power socket is powered only when the ignition is on. You can use piggypack fuse connector on fuse box or connect directly to the supply pin behind the socket. That does not require ripping off the dashboard.

 

I found the accessory power fuse in "Fuse box B" under the dash. With the car off, it's hot with 11.9 volts. So I will either have to pay a visit to the dealership or tap the wire at the back of the 12 lighter/power socket.

 

An update for everyone. I found a way around the whole switched power issue by using an APO (automatic power off) APO3: Automatic Power Off 3 - APRS World, LLC It monitors the power available on power straight from the battery. When it drops below a certain voltage it shut the load off after a certain amount of time. Part of my issue was the whole keyless entry system and the 3 computers onboard the 2020 Fit. Everything works. I still have a minor tweak to make on the monitored power setting. I had it set to 11.8 volts and the power shuts off fine if I have the doors shut. If the door is open and the cabin lights are on, the radio never shut off. So I think I need to adjust the APO to trigger on 12.1 volts rather than the original 11.8.