[SuperCharger]

I bought a ELM327 USB adapter from Amazon which is using PIC18F2480. Firmware version is v1.4b. Band rate is 38400.

I opened up the adapter case, disconnected pin17, pin18 from PCB. Then, I connected the PIC18F2480 pin17(Tx) to Arduino Rx(0), pin18(Rx) to Arduino Tx(1). I also connect the pin19 from the PIC18F2480 to the Arduino Gnd. But it did not work at all.

PIC18F2480 ---------------- Arduino
pin17(Tx) ------------------ Rx(0)
Pin18(Rx) ------------------ Tx(1)
pin19 ---------------------- Gnd

1. Do I need connect other pin/pins from PIC18F2480 to Arduino?

2. If I don't connect the Arduino to the EML327 adapter. The 16x2 LCD connected to the Arduino will display "OBDuino32k v198". Nothing show up on the second line. Even I press the control button nothing happened. Is it normal?

3. I uncomment the "#define ELM", and comment the "#define useECUState". Also I changed "Serial.begin(9600)" to "Serial.begin(38400)". What else code do I need to modify?

4. We need get the +12v source from OBD-II to power the Arduino. Should I use VIN or +5v on the Arduino?

5. Could I use +5v USB power on the adapter to power the Arduino?