All of the technological improvements to vehicles over the past few decades have led to cars and trucks that would seem borderline magical to anyone driving something like a Ford Pinto in the 1970s. Not only are cars much safer due to things like crumple zones, anti-lock brakes, air bags, and compulsory seat belt use, but there’s a wide array of sensors, user interfaces, and computers that also improve the driving experience. At least, until it starts wearing out. The electronic technology in our modern cars can be tricky to replace, but [Aravind] at least was able to replace part of the instrument cluster on his aging (yet still modern) Skoda and improve upon it in the process.
These cars have a recurring problem with the central part of the cluster that includes an LCD display. If replacement parts can even be found, they tend to cost a significant fraction of the value of the car, making them uneconomical for most. [Aravind] found that a 3.5″ color LCD that was already available fit perfectly in the space once the old screen was removed, so from there the next steps were to interface it to the car. These have a CAN bus separated from the main control CAN bus, and the port was easily accessible, so an Arduino with a RTC was obtained to handle the heavy lifting of interfacing with it.
Now, [Aravind] has a new LCD screen in the console that’s fully programmable and potentially longer-lasting than the factory LCD was. There’s also full documentation of the process on the project page as well, for anyone else with a Volkswagen-adjacent car from this era. Either way, it’s a much more economical approach to replacing the module than shelling out the enormous cost of OEM replacement parts. Of course, CAN bus hacks like these are often gateway projects to doing more involved CAN bus projects like turning an entire vehicle into a video game controller.
Wizard Hackers install CRT instrument displays in their car console:
https://hackaday.io/project/10579-retro-futuristic-automobile-control-panel/log/39074-building-the-terminal
It will be interesting to see how long it lasts! Cars can be very hostile environments for electronics.
The environmental conditions (temperature, humidity, and vibrations) inside the dashboard aren’t very hostile, compared to the space under the hood or in the roof. You just need to make sure you have sufficient protection and filtering on the power input, but that’s also pretty easy if you don’t need to draw very large currents. A series diode to reject negative voltage spikes, and a switching power supply that can withstand 40V or more is generally sufficient.
The ISO16750 or older ISO7637 standards are a bit more demanding, but also a lot more expensive to comply with, so most automotive hardware simply doesn’t.
FYI: Microchip/Micrel has some LDO that can handle reverse voltage as well as (shutdown during) over-voltage. Probably made just for that.
Isn’t there like a 100V spike for a few seconds possible when the battery stops charging?
The battery is never disconnected, indeed its used as a (crap)smoothing capacitor for the electrical system when not cranking the engine.
however in a way your right a running car should never have the battery disconnected for just this reason.
Sparky the real issue is with the wiring they gain a certain corrosion on the plugs also anytime you pump a lot of juice through a wire and a plug it corrodes and loses continuity the wire gains resistance which often leads to shorts and electrical fires, burnt out alternators etc. then you have the unknown you don’t know if junior decided to put in a megawatt stereo amp and one of those air pump system that allow the car to jump! Any of those connection could short out causing problems. Think about it a sixteen year old with wire cutters and a roll of electrical tape. My oldest son bought the car of his dream a Trans Am the guy that sold it to him was just that a 16 year old with wire cutters when he installed the stereo he used two foot sections of wire and just twisted the sections together without wire crimp ons or shrink tube every time he hit a bump the stereo would shut off and he would back on the dash to power it on again. It burned out the power amp out twice!
True that, it gets pretty hot inside when the car is parked in direct sunlight for long time, rises upto 65 degree C. However, its relatively colder in the area where the LCD lives, 40-45 degree C, measured it. Vibrations & humidity are insignificant though!
Awesome work Aravind
Thanks QT!
A company I used to work for was investigating a product that melted in a customer’s car. We found that a black box trapped between the windshield and a reflective sun shade can exceed 100C
Yes, definitely it can rise to more than 100degC, but depends on the glass around & cooling/sun cutting film used. In my car, I have a cooling/sun cutting film on the windshield, measured the temperature within the cabin by parking the car in direct sunlight for 3 days straight, it never went past 66 degC & was ~20deg less in the cluster area. Usually I don’t park the car in direct sunlight.
Exactly, this is why every car ever made with a lot of electronics in them, all of the electronics work years down the road.
Oddly enough every car we have, there is some electronic issue in, many times more than one.
The stock stereos croak, the electronic compass dies, cruise likes to die. One of the turn signals fast flashes and it is not a lamp out, it is something in the daylight driving lights box, the tach goes in and out on one car, the dash lights on another. The solenoid that makes the car retain the key on one. I am sure there are other issues. Cars are hard places for electronics. Here they can hit 120 or more on a hot day and -20 or lower on the cold winter day. Plus all the vibrations etc..
And humidity.. Heh, insignificant ? You must live on another planet. Here it is not unusual to have water dripping off of inside surfaces. We have humidity in the 90% range often and it gets hot in the day and cold at night and the water condenses like crazy in the morning before it warms up.
BTW, if automotive electronics are so easy and such a mild environment, why do the stock electronics need replacing?
Hi reg, actually every single piece of electronic equipment (its a German, and there are a hell lot of electronic equipment inside) in my 15yr old car works as it came out of the factory. I don’t drive it light either nor I pamper it too much(does timely engine maintenance though!), about 40% of all roads here in India are pretty much sh*t – harsh vibrations are a daily thing for the car. You can imagine the humidity here as well.
If you have water dripping inside your cabin, you’ve bigger problems to address than an eyesore LCD! I’ve never found water condensation inside my car. Electronics inside cars could fail because some of these systems are programmed/designed to fail after some time as part of “safety & reliability” just like how laptop batteries die after a specific cycle count.
I’m not suggesting that cars are one of the safest environments for electronics, but they’re pretty safe inside a car than out in the open!
Always nice to see people pouring new technology into older cars!
My personal favourite was the DeLorean with a digital dash written in Perl: https://opensource.com/article/18/1/my-delorean-runs-perl
If it’s the dash model I think it is, then you can find the equivalent relatively cheap in VW’s that are being scrapped.
Downside is the backlight will be blue then, or find one from an audi, those have red backlight.
Oh, and you’d need vcds to code it.
I’d be surprised if VAG-COM doesn’t have an open source equivalent by now.
There is Passat B6 with the exact same issue, sadly they fixed it after one iteration. Very hard to find a working replacement LCD from a scrapped one. The backlight is white for these LCDs.
VCDS is useless to swap clusters (or keys or ECUs) without the immobilizer pin which you need to get from a locksmith or using VagTacho or SuperVAG. Dealer cannot provide any pins anymore even if they do the coding for you.
True that Merritt, but its possible to swap the EEPROM chip from the original cluster to an exact same donor cluster, that will work without issues. No need for login PINs.
Now that I did not know. I wasn’t aware the clusters had socketed EEPROMs to be able to do that at all.
Not socketed, 24C02 SMD
Not useless, as it is a user-friendly way of retrieving the specific coding of modules which must be transferred to the replacement. The coding can be programmed also using VCDS.
There are also other free tools out there that are capable of reading/writing EEPROM and ECU although very specific to car generations/ECU model.
Check out s4wiki.com and nefariousmotorsports.com
I just meant on the immobilizer end of things. I have owned VCDS for many years and when it came time to do immo work on my own car, I bought a “SuperVAG” from ebay and it took three months from China to arrive but I was able to pull my pin with it. Supposedly it can write to all the modules including immo like VCDS but I don’t trust it because if it fails in the process you could have a bricked control module, so I only use it to read.
There’s a few HUD install guides on car sites if you want to stop dreaming about the future and be the future. Like, parallel reality 1980s but now future.
I’d like to see this done for the 7th generation Buick Riviera and the first two years of the Buick Reatta to replace their monochrome CRT display. Give it some color and rework the menus to make it easier and more logical to access all the functions.
Unit for voltage is V, in capital.
No. The unit for measuring potential difference is defined a one joule of energy per coulomb of charge.
The SYMBOL for the unit is ‘V’.
One problem that we don’t know about all this technology is how long it will last before it breaks down. There is new advanced safety features such as pre-collision system with emergency braking and pedestrian detection, lane departure alert/assist/keeping, sleep detection and adaptive cruise control
Just so anyone with a VW product knows, there is a company called “Clusters By Litke” (find on Facebook/google) who repairs these (for $200-250) and all other VAG instrument clusters which have common issues like cold solder joints and others.
I’m not overly fussed about rolling computers. A car is for getting from point A to point B, and on weekends point C. Cars did that 100 years ago. Call me when self-driving cars are perfected, that way I can swig from a whisky bottle while barreling down the highway legally.
If your car is less then 25-30 years old, a computer is pulsing a set of fuel injectors based on inputs from at least half a dozen sensor…cars have been rolling computers for more then a generation now.