Custom CANbus Boost Gauges!

The scope of this project is to create a custom gauge cluster to mount in the cubby above the Head Unit. The gauges would be used to primarily to display Boost Pressure, Load %, etc.

I'm hoping this thread will allow me to meet the few others that have interest in these systems to share knowledge and maybe create something awesome!

A few months ago, I was tasked by a friend to make a custom gauge cluster for his boosted IS300. His car had factory navigation, which created an excellent place to install a 7" Nextion display. I then programmed an Arduino R4 using CAN & OBD2 libraries to create a low latency gauge cluster.

It works like this:

Using an MCP2515 CANbus controller connected to the Arduino, I am able to connect to the CANbus through OBD2 to access any supported PIDs available through the diagnostics port. These PIDs then have to be scaled through an equation to get a usable value. The Nextion Display works over Serial; the Arduino then parses the PID values and writes them to the Nextion to animate a gauge.

All the code is C++. Total cost for the Lexus project was around $100. I am Using Sandeep Mistry's CAN and OBDII libraries.


LEXUS PHOTOS BELOW FOR REFERENCE:


Below is a photo from testing. The Lexus is running a ECUMasters standalone ECM





The 7" Nextion Installed in the Lexus Factory Navigation Unit











Nextion 7" display. 3d Printed bracket to hold the R4, MCP2515, and 12v - 5v power converter.







I have started working with my 3rd gen Tundra to develop code and libraries for it's PIDs. My SR5 does not have a boost gauge. After several hours of digging through CANbus data, I've setup my Arduino to parse, scale, and output the Intake Manifold Pressure out of the serial interface. I then took off around the neighborhood. Using Putty, I logged these values to create the following Boost PSI graph:






I've also attached my Spreadsheet showing the PIDs supported by the 3rd gen Tundra. Since all vehicles after '96 have OBDII, this system is not Lexus or Tundra Specific. It would be easy to take my code and make a custom gauge cluster for any vehicle in your fleet.


I will be adding to this thread as my project progresses!

 

My SR5 also doesn’t have a boost gauge so I was wondering if there was a cheaper option than a Banks system to look at boost. Didn’t know you could use an arduino to do that. Super interesting post, following for any updates!

 

Why not access the messages from CAN directly? There's latency polling the network while going through PID. The obvious downside is more work sniffing/deciphering what you're interested in.

Does the display have internal graphics and you're building out the UI from its library, or did you write the front end?

 

If you read this, https://www.tundras.com/threads/dig...uld-you-like-to-see-speed-rpm-mpg-ect.100691/ my setup is very similar to yours. A Nextion 3.5" display that stores the graphics and an Arduino based CAN shield to read in the data.

The problem with the OBD2 Pids is they are a request and receive. You have to request a PID data in on a message and then read/poll for a response. This works fine for a handful or parameters but eventually lag really starts to take over.

I took the plunge and just started reading/reverse engineering the broadcast network messages. If you are going to try this on a 2018+ Tundra, the gateway will act as a "firewall" and keep most of the data from being readable directly at the OBD2 port.