more stupid arduinos

Ya going balls out on this one. Two 2.4″ TFT’s controlled by an Arduino each. The screen is powered by 3.3v so needed a specific Arduino Pro Mini to work it. Used a 7805 5V regulator with appropriate caps on the input and output.


Coolant gauge is set and works good. The gas gauge is tough as it I needed to build a voltage divider and then translate the voltage to the appropriate level in the tank. I need to establish a better averaging or smoothing algorithm as any turns or braking causes the reading to go ape.

Speed sensor is proving to be a lot more complicated. I had it working on the stock ST165 electric speed sensor that the ECU uses for Speed Cut. The instrument cluster is powered by a cable driven speedo which worked until the cable broke. I wanted to be all digital but the stupid sensor get an incredible amount of noise from the engine shaking that it’s terrible. Its an old hall sensor that works on 4 pulses per revolution. Other option is to put an ABS sensor back in the car but I threw them away like an idiot. I still have one in the rear but was planning on pulling it out also.


  • Johan

    How did you set this up? Im trying to get my fuel gauge to with ardiuno but in don’t get good readings .
    Do you got a scheme or something?

    • admin

      It’s hard because the fuel gauge input is so instant that any turn or bump the gauge goes wacky. But if your fuel gauge is just a variable resistor, you just need to build a voltage divider to get a reading that the arduino can see. The stock gauges have a damper of some sort built in. So you would have to replicate that with programming by taking an average or something. I have up on the project after I sold the car.

  • Leave a Reply

    Your email address will not be published. Required fields are marked *