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need help finding the right circuit design..please look

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blokroknbeats

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I am hoping someone here can help me. I am very new at this so i am sorry if this is a stupid question. I install electronics in cars, audio/video etc. On my current personal project i am attempting to add an aftermarket cruise control and control it using a infiniti g35 steering wheel (not in a g35)
There are 4 switches for the cruise control each with a resistor. Ground is supplied to each switch and the outputs pass through resistors to a common output wire. Each switch has a different resistor value. I am trying to find a device or circuit that will allow me to have a separate output (either ground or 12v with at least 150ma to drive a spdt relay) for each switch. This will be in a car so i am using 12vdc.
Sorry if this is basic but i would appreciate any help, even if its just a point to the right direction.
 
Get an LM3914 IC wired as in the attachment. Connect a resistor between pins 6, 7 and pin 5, and then connect the output wire from your steering wheel to pin 5. Pick the resistor so that when the button with the highest internal resistor is pushed, the resulting voltage divider produces an output voltage of about 3.5V. The other buttons, when pressed, should create output voltages less than 3.5V

If all of the LEDs were hooked up, you should get four different LEDs to light as each button is pressed. If one of the buttons straddles two adjacent LED states, diddle the resistor to move the ranges a bit. Now substitute pull-up resistors for the four choosen LEDs, and hook up a transistor and relay for each of the four...
 

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Reread my post again. I modified the description of how to hook up the wire from the steering wheel to the 3914.
 
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