This is sort of audio related. I have an after market touchscreen headunit in my car. It is a basic Sony radio with just enough features that I need. I have connected all the wires to the harness I had to buy to fit my car. That included antenna, illumination (dimmer), constant power (for the clock memory), power, speakers, etc. So by default, when I turn my lights on, the screen dims, when I turn the ignition on and radio switches on, the antenna will go up as it is motorized. It all works as it should but I need more control. For example if it is raining during the day and I have to turn the wipers on, the screen dims and it is hard to read. The radio I have doesn’t have an off button. I can turn the screen off but the radio stays on in the background. This means that the antenna is always up. While it is fine when you drive in the city or on a highway, when I off-road, I am simply asking for a trouble with a 2.5 feet of thin metal rod sticking out of my fender. It is no match for some of the branches I meet when I wheel thru the woods.
The solution to my problem is super simple. All I need to have is a way to manually control the dimmer, antenna and radio (on/off). So basically what I did is to put a switch in-between the radio and car’s wiring for the following wires:
- Power on/off
- Illumination (dimmer)
I had a blank space on my dashboard where I could put the switches. Problem was that the small cover had only space for two buttons so I put one on/off switch and one on-off-on DPDT switch. The on/off switch (round one) controls the dimmer function. The DPDT switch is wired so in one ON position I am switching power to the radio with the antenna staying off and the other position that turns the radio and antenna on. Of course the middle OFF position switches the whole radio off which is one of the functions my radio is missing altogether.
Here are few photos I took of the switches. I have to say, it works great. I can now control all the radio features I want.