# Need swc help



## larryharper6464 (10 mo ago)

Hello I have a 2011 Nissan Sentra SR with steering wheel controls for the radio. I need to know if anyone know which wires going to the factory radio that is controlled by the controls on the steering wheel. I just installed a double din touch screen and wanna be able to control the radio from my steering wheel. Any help will be much appreciated.


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## VStar650CL (Nov 12, 2020)

Setup is identical for Navi and Non-Navi. Note that the outputs aren't digital, they're a multiplexed resistor-divider network that outputs a different voltage depending on which button is pressed. If your new AV has a self-learning function for analog input then it can probably read it, if not you may be out of luck. The outputs are ganged for "down" and "up" for the Seek and Volume functions, so if you can live with one or the other then you make them digital by opening the switch and tinkering the resistors.


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## larryharper6464 (10 mo ago)

My new stereo has the learning capability but I need to know which wires to hook up so it will learn.


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## VStar650CL (Nov 12, 2020)

They're all multiplexed on the Blue (L) and Pink (P) wires. L is Hang Up, Seek Down and Volume Down. P is Phone, Seek Up and Volume UP. Light Green (LG) is the ground for the resistor ladder. The ladder originally worked with a pullup resistor inside the AV Unit to provide the positive voltage, so you'll need either a pulled-up input on your new AV or an external pullup resistor. You can generally find out if your inputs are pulled up by measuring the voltage with the AV powered and the pins open. If they read 5V or 12V, then there's already an internal pullup. If you need an external, you can find a good value by ohming from the L pin to the LG pin with the spiral cable disconnected and the Volume Up button pressed. That will give you the total value of the two ladder resistors inside the switch. A pullup around double the total value will give you an approximate 5V level from a 12V pullup, or if you have a 5V source available then use a pullup equal to the total I.e., if the reading is 2000 ohms, a pullup of 3900 ohms from 12V will give you about a 5V ladder, or use 2000 ohms from a 5V power source. L and P will each need their own pullup.


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## larryharper6464 (10 mo ago)

Ok thanks I will give it a try.


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