https://www.youtube.com/watch?v=MeUgWF98Ndw

It 's about an Arduino project connected to an ELM-327 OBDII Bluetooth through a HC-05 bluetooth module.
The HC-05 is connected to Arduino with serial UART, and is configured (with AT commands) as Master to connect to ELM-327 OBDII Bluetooth which is the slave.
As soon as connection established begins the initialitation (with AT commands) of ELM-327.
After that we can read Engine RPM from car's ECU.
Next just display the RPM to 7-segment LEDS.
Shift Lights going ON at the RPM that we configure pressing the button at desired Engine RPM, value is stored to EEPROM.
Please feel free to comment or suggest or contact me.
Code is here http://www.kokoras.com/OBD/Arduino_HC-05_ELM327_OBD_RPM_Shift_Light.htm, schematics will post as soon as possible.

Kostas

http://www.ebay.co.uk/itm/251208216925?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

http://www.amazon.co.uk/ELM327-Bluetooth-Wireless-OBD-II-Diagnostic/dp/B006JJZVQE/ref=cm_cr_pr_product_top

 

Car stuff is off limits Kostas. The mods will be by in a bit to close this thread, sorry.

Bob

 

Neat project, since it doesn't modify a car in any way but instead just reads the OBDII data I can't see why it would violate forum rules.

 

Every modern car has an OBDII connector for diagnostics located close to the dashboard. I also would not consider this automotive modification more than plugging in some equipment in the car cigarette lighter connector.