So I built a few canbus/car electronic projects… anyone got ideas for more?

[Gripless]

Have made some esp32 gauges and displays for my car.

does anyone want something like this or have any suggestions?

 

All these are setup over wifi with webpage to enter settings. It’s pretty basic so far but could add presets to auto configure for different generations.

 

Tire pressure over Bluetooth round display that you turn outer ring to see different pressure units, and push to turn off display. It comes back on for new alerts etc. Can add sensor ID and working on a discovery feature. I theory the 2012 or newer cars could have this canbus the data to the OEM screen. The older cars have a physical wire to the dash lamp.

 

RPM bar display 16-40 led F1 style. Has rpm limits and flash rate etc settings. Currently only canbus but could do pulse counting so works with older rpm signal.

 

DCCD display. Currently no settings just smart watch screen that can show auto with +- manual and the diff lock level. Graphics need a lot of work.

 

canbus keypad. There is a opencan version online so could be auto configured by most aftermarket ecu brands. Or web page where set canbus id and then ecu can receive messages when buttons are pressed. Could also receive messages from ecu to turn on/off illumination behind keys, or set colour.

 

could retrofit a LCD to old cluster so can display more data as well as the check lights so stays WOF compliant.

Edited April 25 by Gripless
Retrofit idea

[Gripless]

Early version of TPMS testing layout and colouring. Currently the magenta lines are grey and text is white unless alarm then red or orange.

 

Screen is 1.3” and outside is about 52mm 

similar size to 08 aircon dials.

Thinking 3 will fit across a single DIN stereo panel size, so could have TPMS, G force sensor and something else.

[Gripless]

Working on prototype 2 for shiftlight.

Prototype 1 was a bench top proof of concept and was just wires with alligator clippers connecting everything.

This one is fully cased with OBD2 connector, and buttons to activate wifi for settings and turn off display etc.

There are 3 options on how to connect the display and sensor to the control box, and where the button(s) are. This one is 3 buttons in the back of the led bar. 

[Gripless]

Tested and working.

25x225mm with 40 led

17x182mm with 32 led 

 

options to set via wifi

redline

flash warning after redline

flash rate/speed

minimum rpm to turn on eg off until 3000rpm. Rescales led so still uses al of them.

pattern. Single line, inside to out, outside to in.

colour palette 

 

thinking of adding canbus id via wifi so can be any ID, plus can send messages from aftermarket ecu telling it how many LEDs to turn on. That way a table or math block in ecu can control it.

[Gripless]

Made a few little changes and fixes.

• better canbus ID filtering
• imcreased processing speed
• watchdog timer that reboots if no can rpm data for 10 seconds
• Small memory leak found that caused issues after 4-5 hours at 2000 packets a second.
• added tiny 1cm wide OLED screen for status information. 

Looks like prototype 2 will be viable for use.

 

The only remaining  issue is triggering the power on and off, but that could be all software sleep.

 

After that is for other people to try it and get feedback 

[Andy_Mac]

Something rectangle that sits in the top 1/3rd of the vents would be cool, like a P3 gauge but with more specialised info available. Having DCCD there would be cool 

[Gripless]

Only sti specific stuff I know of is DCCD and G-force sensors.

 

working on some PCB design bits and updating to use the newer canbus chips.

 

Adding a thermocouple circuit as a test and they cost way to much.

[Gripless]

Well ordered the first circuit boards for prototype 4.

 

WTF cost was USD10 shipped for 10 custom boards.

 

It is insane what you can fit into a tiny space.

The board is 20x76mm and max 5mm high with all these features: 

now 1cm longer and added reverse polarity protection. Plus no need to replace diodes for 24v vehicles.

 

• fuse, self resetting
• short-circuit aka reverse polarity protection 
• 12/24v switch mode power supply for low heat 90% efficiency 
• Just need to swap the fuse for use in 24v vehicles
• Optional ign switch input to power up
• Electrical power noise filtering
• Electrical filtering ADC pins
• Spare 5v and 3v3 volt outputs
• 4x static (ESD)protection for buttons and knobs etc
• 12 general purpose input/outputs
• Current generation CAN 2.0 controller with listen real listen only mode. 
• CAN bus noise filtering, ESD and voltage spike (TVS) protection
• optional canbus termination for aftermarket ecu 2nd bus use.
• ESP32 module with dual core cpu, wifi and Bluetooth 
• connector for firmware update and Arduino IDE supported

This is massive overkill and parts are high spec low tolerance ones.

board can run as almost anything, supports full LCD displays etc. 

 

 

Adding web configuration for colour of each led and rpm it triggers at, mostly done.

You can set can ID and bytes via web to look at so supports most cars and aftermarket ecus. 

Also want to add an aftermarket mode that allows ecu to do some cool things that I have seen any other product do.

 

 

Edited June 27 by Gripless

[Gripless]

Boards have the pins labelled and aren’t locked to custom firmware so can be reprogrammed by anyone.

 

So far estimate around NZD$50 with the LEDs in case as shift light. Main 3 chips are around USD$9

[Gripless]

Have a week or two before the first version turns up and no improvements to make until I can test the board.

 

In the meantime I had the idea I could adapt what I have to a board that plugs into this…

https://www.aliexpress.com/item/1005008877505362.html

that way it’s really cheap to have a canbus connected mini display.
 

Anyone can cut or print a custom front panel or mount it behind a small cutout. Only a few screws hold it together which makes it simple to assemble.

Being shipped from China as DIY no need for certification like CE or FCC for radio(wifi) devices.

That board already has 3 usable buttons (plus reboot) and 3 spare in/out with serial port. 2 is enough for canbus board.

It has place for power in so I just need to do a 12v to 5v section and the protection circuit.

[Timmah]

So, these little gauges can hook into the CAN system and then ... read whatever? Clever! Another reason for me to get a Link..

[Gripless]

5 hours ago, Timmah said:

So, these little gauges can hook into the CAN system and then ... read whatever? Clever! Another reason for me to get a Link..

Pretty much.

The board and chip can read any can up to 1Mb/s speed what you do with it is open to how much coding you can do. The ESP32 that it’s based one has built in canbus support so it’s not as complex as it appears.

 

I’ll have some basic framework coding for it, along with the web config examples. That way there is no need for an app as the ESP32 can be a wifi access point and you connect to it, and it shows the settings.

I have two prototypes running on the OEM stock canbus. One does rpm shiftlight the other is DCCD display.
The tire pressure one hasn’t got off my desk yet as it has an annoying mounting system but it works, mostly. There is no discovery scan yet, you have to know the max addresses of the sensors.

There is another bigger display that is popular CYD 2.8” with touch control for NZD$15-30 as well, that seems like it maybe a good idea to do as well. Power and canbus would be 1/4 to 1/3 that board the rest could be holes for whatever other electronics.

 

[Gripless]

First boards turned up.

waiting on the rest of the components to arrive so can test them.

 

 

 

[Gripless]

Found out bad solder is a thing.

Just had a section of solder wire go on and acts like lead free. Extra flux etc makes no difference, it looks like aluminium burrs even when heated. Problem was it is under the pads on a microcontroller and shorting ground to power. New solder and drowned in flux it just turns to sand like beads and won’t flow. 

 

I tested some more of the roll and it has sections that don’t melt correctly and are matte without shine and do flow or stick to the tip of the iron. The 2-mm from the heated end looks matte and nasty as well. 

 

Ordered new roll of solder so that is more delay.

still have other cool things on the go so back to learning to code.

[boon]

I had a similar experience recently. Thought my iron was faulty, biffed it and bought a flash new one, same result. Annoying to say the least, had to rework a whole bunch of s*** joins on a board afterward.

[Gripless]

16 minutes ago, boon said:

I had a similar experience recently. Thought my iron was faulty, biffed it and bought a flash new one, same result. Annoying to say the least, had to rework a whole bunch of s*** joins on a board afterward.

Also learned that some solder rolls are weighted. Not the solder but the plastic roll. The trick is they use heavy webbing between the hole and the outer layer the solder is rolled on. Some YouTube channel weighed them and more than half the stated weight is plastic

https://youtu.be/lQ91gktACXw

 

[Gripless]

Managed to finally get some more progress as parts arrived last week.

 

I soldered up the switching and regulator power supply using solder paste and heat plate which worked on all but one tiny chip. Solder bridged 2 pins but that was easy to clean up.

I fitted both diodes backwards, one as didn’t check, the other I knew was backwards but was working off old schematic.

 

All voltages were good, so tomorrow I’ll add the can bus section and hopefully the micro controller.

 

I missed ordering the tiny capacitors for the canbus but the voltage sections are overly filtered and won’t impact testing. The static protection chip wasn’t ordered either as that want needed to test.