[Anthony Pray] had his car stereo stolen. When thinking about replacing it he realized the he and his wife never used it for anything other than an Auxiliary connection to play songs from their cellphones. So instead of buying a head unit he pulled an unused home audio amplifier out of a dark corner of his house and wired it to the car speakers. Problem solved, except that the under-dash installation meant the only volume control is on the phone playing the audio. He decided to build a wireless audio controller that would let him send commands to the phone without quite as much distraction from the road.

The device you see above is his creation. What a beauty. But seriously, it’s so random and hacked together how can you not love it? And, it works!

The frame is made from plastic coat hangers, and the wheel is an old RC control knob. There’s even a play/pause feature built from the clicking properties of a retractable ball-point pen. A Cypress PSoC board reads the knob and pen positions, then pushes commands via a Bluetooth module in order to control the phone. He recorded a testing video (after the break) which gives you a better look at the functionality of this setup.

The CD player in [mukmuk’s] 2005 Subaru Outback gave up the ghost, and faced with a long road trip ahead of him, he was desperate to find a way to listen to something other than static-filled radio. He considered a 3rd party auxiliary input solution, but after seeing a similar aux-in hack here, he figured he could give it a go himself.

The stereo head unit design was changed between the 2004 and 2005 model years, so while he had a good idea of what to look for, he had to find the proper components on his own. Once he identified the radio module, he was able to locate the left an right input pins through trial and error. He carefully soldered a 3.5” audio jack to the head unit’s input lines, wiring it to cut off the audio signal from the radio whenever his Zune was plugged in.

Everything was reassembled, and the input jack was inconspicuously mounted in a cubby hole just above the stereo. [mukmuk] is quite happy with his modification, and we’re guessing his road trip was far more pleasurable as a result of his work.

[Jordan] writes in to show us his hacked up car stereo. [Jordan]‘s 2004 Subaru, like many of our cars, does not offer any kind of auxiliary input, and aux-in/mp3 adapters tend to run on the not so cheap side of the price scale. Even a replacement head unit was too rich for his blood. So it was time to wire something to the old head unit.

On inspecting the radio’s PCB [Jordan] managed to locate the traces that carry audio from the FM receiver to the stereo’s amplifier.  Most aux input hacks we have seen involve fooling the stereo into thinking some media is inserted, even if interfacing with the audio lines on the PCB. These require that the tape/CD functionality be altered, perhaps permanently. Even worse you may have to shlep around a blank CDR with a bunch of tracks on it! All just to fool the stereo into enabling audio output.

Instead [Jordan] targets the audio lines from the FM stereo, since radio is always enabled when active. Once the audio traces are located they are severed  and bypassed with a 1/8″ stereo plug. This setup allows the FM audio signal to pass through the connector when disconnected, and cuts off any radio audio once your mp3 player is. We have seen this same method used on a vintage stereo hack as well. Nice work!

[war6763] sent us this hack to power an amplifier in a MINI Cooper. Apparently, aside from being unconventionally handsome, they’re also unconventionally wired. Amplifiers are generally wired to the ignition or stereo and turned on when the car is turned on. Due to some strange wiring, this just isn’t possible in the MINI Cooper. Some people use the cigarette lighter to power on their amplifier, but [war6763] wanted something that left his cigarette lighter free for other things. He built a circuit that monitors the cars built in USB input line and turns his amp on and off accordingly. The entire unit cost around $10.00. You can see the video demonstration after the break.

[Gabe Graham] sent us this step by step process of building a dock for his Zune and hacking is steering wheel controls to work with it. Like many of us, he was not happy with the performance of those little radio transmitters that hook to your mp3 player. He remedied the situation by mounting a dock for his Zune onto the console and patching into his stereo. The sound quality was great, but controlling it was a pain.

He had one button left on his steering wheel that was not needed for anything.  He created a custom controller for the Zune that would issue different commands based on how long he held the button on the steering wheel. If the button was held for less than half a second, it would skip tracks, any longer and it would pause. Though he could possibly clean up the look of the LED sticking out of the console, the over all effect is quite well done.