r/CarHacking • u/Matt_brnoutltd • 2h ago
r/CarHacking • u/ScuderiaMacchina • Feb 02 '17
Car Hacking Subreddit Intro
Hi rch, we have added a lot of people lately with intro posts on other subs like the one below. We also usually get about 10 subs a day from people just stumbling in here. So I wanted to create a welcome post, to kinda show them what we are about and how to get started. If anyone has anything to add please do so. If anyone has any questions about us or where to start do so here.
Our goal is to create a highly technical car subreddit, a place for automotive engineers, senior technicians, full blown car nerds, or people who are working towards one of these. We are interested in the inner workings of cars and today that often involves electronics. While we see electronics as the priority we are pretty liberal in allowing other topics as long as they somehow fit our goal of trying to understand cars. So things like DIY aero, suspension setup and other things the community is hacking on come up. In general our other tangential interests include: Modern cars, New tech, Open source hardware/software, DIY, hot rodding, eco modding, customization, security research, right to repair and more.
We started this subreddit about a year ago. Right now we have 3000 people and discussion is just starting to get good. Most of our members found us through maker or engineering subreddits. So I wanted to reach out to more of the car communities and try to grow our knowledge base.
Our name is r/carhacking and I know the term hacking can be offputting to some as it has a bad connotation. When someone says they are “hacking” their car it generally means they are trying to reverse engineer it for any number of reasons like to find security flaws, make upgrades, make repairs, or just understand how it works.
Here are a couple examples of posts that have been popular so far. A lot of our posts focus on beginner through intermediate projects using arduino and readily available hardware for the purpose of learning and or not paying a premium for things you can make yourself:
More advanced projects:
- Subaru performance hacking
- Tesla retrofit
- Mazda 3 tuning
- DIY Mazda ECU
- Truck Transmission Controller
Relevant news/ research:
If your new our documentation is a good place to start
If you aren't new and you’re interested in helping out please consider:
- Improving documentation - think about what resources have helped you
- Spread the word - this is a niche community that is pretty spread out, but there is a lot of potential if we can get together on a third party site like this
- Work on the theme, sidebar and flair - this is next level community stuff that isn’t necessary, but it’s fun to work on when you have the time.
- Modding - right now we are fine, but we might need help in the future as we grow
Let me know if I missed something or got something wrong.
r/CarHacking • u/ScuderiaMacchina • Feb 27 '21
CAN CAN bus and car hacking getting started resources
I get asked how to get started with automotive networking, car hacking, and CAN almost weekly. I often direct people to this subreddit, so I figured I would help out and post some resources I have found and think are a good place to start.
learning resources:
Car Hacking 101: Practical Guide to Exploiting CAN-Bus using Instrument Cluster Simulator
- Part 1 - Setting Up (a virtual test environment) - Feel free to skim everything before "Setting up the virtual environment". While interesting, none of that is vital to get started.
- Part 2 - Exploitation (sniffing, replaying, and attacking CAN traffic)
- Part 3 - SavvyCAN, Fuzzing CAN Frame and playing around with CAN frames
I also direct people to the Car Hacking Village to get some hands-on experience. They put on great conference talks, demos, and contests. Looks like they are even working on some “getting started” content.
And of course, The Car Hacking Handbook is a great resource.
I will add more as I think of them. Please add your finds in the comments.
Tools:
Good wiring diagrams and car manuals are essential. This is pretty much where my research starts for each project. You see how things are networked and what to expect to find on CAN. You'll quickly learn to recognize things like gateways. You can also use the troubleshooting section to understand things. For example, what things do I need to control to start the car?
I like:
- prodemand (I pay $170/mo for a shop subscription, I think you can purchase it for individual cars, but be careful you often have to jump around to find a year that has complete diagrams)
- Identifix (probably what I would buy if I was starting over)
Basic hardware: Here you will be working with things like Arduino, Linux, SavvyCAN, and Can-utils. You have to learn to do a lot yourself, but these tools are more open for you to make them do what you need.
Tools designed by the community I use:
The above articles offer a pretty good step-by-step guide to getting started with the Macchina M2.
Any cheap “Amazon special” OBD2 dongle will come in handy from time to time. They are all based on something called ELM327. "ELM327 abstracts the low-level protocol and presents a simple interface that can be called via a UART". This abstraction has fundamental limitations that prevent it from being useful in most serious applications. But, it is sufficient for reading and clearing some codes and that sort of thing when you’re getting started.
r/CarHacking • u/Matt_brnoutltd • 2h ago
CAN MIB2 Bench - Ignition ON conflict
Hi everyone,
I'm currently building an MQB testbench on my desk to sniff CAN data. My setup includes:
- MIB2 Unit: 3Q0 035819 C
- Gateway (J533): 5Q0 907 530 E
- BCM (J519): 5Q0 937 084 AJ
The Problem: Im using an Arduino with an MCP2515 on the Convenience CAN bus to wake up the system. Currently, I am injecting 0x3C0 with payload 0x03 (Terminal 15 ON). However, because my BCM is connected and doesn't see a physical key turn, it is aggressively broadcasting 0x3C0 with payload 0x00 (Ignition OFF). The Gateway forwards both conflicting messages to the Infotainment CAN, causing my MIB2 screen to constantly flash on and off.
My Questions:
Does anyone know the specific CAN ID and payload for the Steering Column Electronics (J527) or KESSY module that simulates the physical key turn / Terminal 15 ON command on the Convenience CAN?
Thanks in advance for any help or pointers to relevant .dbc files :)
r/CarHacking • u/Accurate-Block595 • 6h ago
Cool Project Find Comunication Protocol
Am in the stage of developing the software of my Can sniffer, {Esp32 + sn65hvd230}, i succeed gaining raw can bus data, BUT i want to upgrade t the level of diagnostic scanner,
So am learning about Licenses and ISO communication Protocols, The thing is that am a totally beginner, and this step will have direct treatment with ecus,
So am seeking some resources about this and how to develop this kind of communication, it will really take my device to a next level, ill be thankful to receive some resources and guidness.
r/CarHacking • u/KeySprinkles3425 • 12h ago
Scan Tool I’m looking for a good obd2 I have a 300-400 budget looking mainly one that is compatible with a Honda civic 14
I’ve been looking at autel and foxwell I need a reader that can program a Ecu if I replace it and that could read Srs codes any suggestions please and thank you
r/CarHacking • u/pllxo • 9h ago
Scan Tool HELP, is this a tracker? is this OBD scanner an aftermarket?
I don’t know much about cars but I’ve been telling my friend that I don’t remember any pink bits when I last put the OBD in.. I did research on ai and he still thinks I’m just being overly paranoid.
New things I noticed that he brushed off
* new beeping sound
* beeping sound coming from the driver side
* beeping sound stops when he walks away with the key
* max speed @ 50km started showing
* EPC light came on
*am I overly thinking things or is there like some sort of glue residue out of the obd holes
* there’s a loose item somewhere where I can hear it occasionally when driving
* battery drain in car
Also I’m aware that the original Audi wiring are wrapped in black? No? Correct me if I’m wrong
r/CarHacking • u/Primary-Coconut-3781 • 1d ago
Community Can bus sniffing help
Hi, I followed this tutorial (https://logos-red.com/blog/how-to-hack-a-car-wirelessly-sending-remote-commands/ ) on how to get can bus data from the obd port. Assuming i soldered everything correctly, why am I not seeing anything on SavvyCAN? I used the esp32 and I tested it on a Golf 8.5 GTI, the gateway behind the obd port blocks the sniffing or there is something else in the tutorial I used? Using another microcontroller would help?
r/CarHacking • u/Successful_Ad7206 • 2d ago
CAN BCM - no CAN communication, full component-level diagnosis done, need advice on 0990-9377 ASIC
Hi guys,
Honestly I read most of what exists online about these modules, but my BCM module from my XC90 D5 suddenly threw "Brake failure stop safely" + ABS + anti-skid, speedo dead. VIDA shows CEM-1A5F (communication with BCM missing), BCM not visible on network. I cleared all DTCs in VIDA — nothing else comes back, only the no-connection to BCM. No accident, no water damage, fault appeared out of nowhere.
Before blaming the module I checked the car properly:
12V at BCM connector supply pins with ignition on and off, grounds OK, all fuses OK (checked both sides with meter)
Checked all CAN wiring related to BCM in the car including at the CEM connector - all good
CAN at BCM plug seems alive: 2.6V / 2.3V idle
Termination checks out: ~130 Ω harness side, ~135 Ω module side (2×62 Ω internal), ~60 Ω together
VIDA talks to ECM/TCM fine through the CEM
Connector cleaned, pins good
So the car is 100% healthy. Then I opened the module (cut the welded case) and put it on the bench (12V to pins 1/32/4, GND to 16/47). Findings:
Draws stable 225 mA @ 12V - wakes up, no shorts
Resoldered all the press-fit pins first (the usual weak point) — no change
All rails present: 12V, 5V (at the ASIC), 3.3V + 1.8V for the MCU. The 3.3/1.8 come from the 14-pin Motorola 9369.1D — I measured it: 12V in, both rails out, two switch pins running ~47 kHz. So on my board this chip is WORKING (I know it's the famous killer on modules marked MK60 (or MK25) - not my case)
Crystal oscillates, 5.50 MHz stable
The MCU (TI TMS471 R1VF34A2PZQ) is definitely running - several pins show digital bursts repeating about every 1 second, looks like a fault/retry loop
B82790 CAN choke windings OK (0.4 Ω)
But the module NEVER transmits. I scoped the choke pads (ASIC side) through multiple power cycles with normal trigger - total silence, not even one attempt at boot. Same at pins 11/15.
So by elimination everything in the chain is good except the CAN transceiver section inside the big ATE ASIC 0990-9377.1D3 (5CC6L7TB, made by TI). It has 5V, it has a running MCU next to it, and it never says a word.
I know what most people will say - send it for professional repair, and I've read all the recommendations. But I'd rather fix it myself than spend that money. I enjoy soldering, I have hot air and decent equipment, and I have time to experiment. Worst case I learn something and the pro repair option is still there.
My questions:
Can anyone confirm the CAN physical layer in these Volvo units is inside the 0990-9377? Does anyone have any pinout info for this ASIC (CANH/CANL to the choke, TX/RX from the MCU, enable pin)?
Has anyone actually fixed the "no communication but everything else runs" by swapping the 9377? Or does this signature usually mean the CAN peripheral in the TMS471 itself (bond wires)?
Is there some init handshake between the TMS471 and the ASIC (SPI config, enable, EEPROM check) that can fail and keep CAN dead like this?
Photos of the board and my best take at making a schema attached. Thanks in advance - happy to do more measurements if someone tells me where to probe.
r/CarHacking • u/Immediate-Dog1957 • 2d ago
UDS Cracked SecurityAccess (seed/key) on a Kefico CPEGD ECU — 2014 Veloster Turbo, TriCore based, looking to collaborate
Cracked SecurityAccess seed and key on the Kefico CPEGD ECU (TriCore based) in a 2014 Veloster Turbo 1.6 T-GDI, verified live over CAN, and also believe that I understand flash checksum algorithm so patched calibration files validate correctly. I'm coming at this from the reverse engineering and embedded side rather than a traditional tuning background so go easy on me if I'm missing something obvious, but I think this is solid progress on a platform that doesn't have much public documentation, only expensive commercial solutions.
I would love to compare notes with anyone else working on Kefico or Hyundai/Kia ECUs, and would really appreciate any OEM bins from other years, trims, or calibration IDs, or any documentation like A2L files, XDF definitions, or disassembly notes.
Thanks!
r/CarHacking • u/Fit_Junket_8982 • 2d ago
Community Has anybody found a way to unlock SFD 1?
Hello everyone,
Has anyone found a way to unlock SFD1 on VW vehicles?
I'm trying to make a few coding changes on my car. I have a clone VCDS, which is able to retrieve the SFD challenge token, but I don't have a way to complete the unlock.
For my use case, paying €180/year for an OBDeleven subscription just to unlock SFD once or twice doesn't make much sense. I'm mainly looking for a free or at least a cheaper alternative.
If anyone has found another method or knows of a service/tool that can do this without the yearly subscription, I'd really appreciate it if you could share it.
Thanks!
r/CarHacking • u/Ok-Tax-7888 • 1d ago
Original Project I've been working on a new app with Google AI Studio.
I've been working on an app off and on with Google since I can't seem to find the type of app that I've been looking for for quite some time, I have it posted up on GitHub and I would really like it if you guys could take a look at it and give me any feedback for changes that I can make or new features that I can implement. This is the first app that I've ever made, so please go easy on me and any help would be greatly appreciated.
https://github.com/Freshman0000/OBDash
I have an APK I have a version of the app that I can email to you if that's something that you're interested in.
If any of you have been using AI to work on an app, I'm sure you're already aware that even though it's helpful, it's still a pain in the ass to try to get it to do the things that you want. Especially look the way you want. So, it's taken me a little bit longer than I had originally anticipated. Like, by three months.
r/CarHacking • u/NIDGE11 • 3d ago
Original Project Nintendo DS CAN Gauge
I’ve been working on a project inspired by the TurboXS DTEC, an early-2000s tuning device that used a Game Boy Advance as its display and interface.
The idea was to take that general concept and do something similar with a DS, using a homebrew ROM running on the original hardware.
The current prototype uses a cheap ELM327 adapter to retrieve live vehicle data, which is sent to the DS over a custom link. At the moment I’m working with data such as:
* Vehicle speed
* RPM
* Coolant temperature
* Battery voltage
The longer-term goal is to move beyond the generic OBD interface and interface directly with the vehicle CAN bus, allowing the DS to receive more detailed vehicle data.
Still very much a work in progress, but I thought it would be interesting.
r/CarHacking • u/WingmanMoto • 2d ago
ELM327 Are all ELM327 created the same?
I've been working on a personal app project and testing it with a vLinker MC. It's working well to capture OBD2 and CAN bus data, but I'd like to test it with generic ELM327 or other devices to see if there are any compatibility differences I should address before publishing. If you've experienced any problems with specific brands or models of OBD2 adapters, regardless of which software you're using, I'm interested in learning which one. Unwanted disconnections, buffer problems, pairing issues, or similar issues in particular.
As an aside, I've yet to find an adapter that supports both OBD2 PID and raw CAN at the same time. Is this just not possible?
r/CarHacking • u/MarkMarv • 2d ago
Cool Project Find Lexion CarPlay Monitor
Selling a new and unused Lexus NX(2015-2017 ) Lexion Linux Monitor for CarPlay® and Android Auto™
Ordered it in and didn’t even up installing.
Save a few hundred off the website price.
This will work on Lexus NX(2015-2017)
Vehicle Controller Type - Touchpad
Comes with AHD Rear Camera as well.
Upgrade your Lexus with the Lexion LX10S—the world’s first Linux-based CarPlay monitor. Swap your outdated 7inch stock screen for a stunning 10.25-inch wide, high-res display. Enjoy lightning-fast 5–10 second boot times, seamless CarPlay and Android Auto, and premium Mark Levinson sound through factory Bluetooth. No SIM, no YouTube distractions—just a safer, smarter ride. Fully supports aftermarket cameras and all stock features at an unbeatable price.
Linux-Powered Performance: Linux OS monitor, 5-second boot
Stunning Display: Upgrades 7inch to 10.25inch wide screen.
Seamless Integration: Full CarPlay® and Android Auto™ support
Premium Audio: Factory Bluetooth delivers flawless sound.
Easy Install: Plug-and-play, retains all OEM functions.
Will ship anywhere in North America, asking $500 Canadian or $350 US.
Message me
r/CarHacking • u/Embarrassed-Cover294 • 3d ago
Article/news FlowECU has now passed 500 downloads worldwide
r/CarHacking • u/MarkMarv • 2d ago
Original Project Lexion CarPlay Monitor
Selling a new and unused Lexus NX(2015-2017 ) Lexion Linux Monitor for CarPlay® and Android Auto™
Ordered it in and didn’t even up installing.
Save a few hundred off the website price.
This will work on Lexus NX(2015-2017)
Vehicle Controller Type - Touchpad
Comes with AHD Rear Camera as well.
Upgrade your Lexus with the Lexion LX10S—the world’s first Linux-based CarPlay monitor. Swap your outdated 7inch stock screen for a stunning 10.25-inch wide, high-res display. Enjoy lightning-fast 5–10 second boot times, seamless CarPlay and Android Auto, and premium Mark Levinson sound through factory Bluetooth. No SIM, no YouTube distractions—just a safer, smarter ride. Fully supports aftermarket cameras and all stock features at an unbeatable price.
Linux-Powered Performance: Linux OS monitor, 5-second boot
Stunning Display: Upgrades 7inch to 10.25inch wide screen.
Seamless Integration: Full CarPlay® and Android Auto™ support
Premium Audio: Factory Bluetooth delivers flawless sound.
Easy Install: Plug-and-play, retains all OEM functions.
Will ship anywhere in North America, asking $500 Canadian or $350 US.
Message me
r/CarHacking • u/Coast_Leather • 3d ago
Community Diesel engines course
hello everyone
Can anyone suggest a free online course for diesel engines diagnostics ??
thank you
r/CarHacking • u/Ill_Phase_6367 • 3d ago
Tuning Aide pour les fichiers automatiques MHH
Bonjour, je vous serais très reconnaissant si quelqu'un pouvait télécharger ces fichiers pour moi. Je suis bloqué avec 25 ans de base de données Audi, mais elle ne contient pas les fichiers dont j'ai vraiment besoin... Si quelqu'un pouvait m'aider, que Dieu le bénisse. :
r/CarHacking • u/eyecontact0000 • 3d ago
Scan Tool ecu connect to computer
Hi,
I have a question about a car ECU. I bought an ECU from a Mercedes W205 C220 CDI. I downloaded the wiring diagram from the internet, and based on it I identified the required pins (I tried to upload pictures showing the pinout). I connected +12 V, IGN, and GND to a laboratory power supply. I also connected CAN High, CAN Low, GND, and +12 V to an bought OBD2 connector. I tried to connect to the ECU using a diagnostic scanner (autoscan - older version), but I couldn't establish communication.
Does anybody have experience with this ECU or know what I might be missing?

r/CarHacking • u/fr3shh23 • 4d ago
Scan Tool ULPT request: how to get autel scanner updates/renewals for free or cheap?
I have the autel maxipro mp808.
r/CarHacking • u/Bitter-School-62 • 4d ago
Scan Tool Launch x431smartlink with ford fdrs
Hello, i need help with making the launch x431 smartlink show up as an option to select in fdrs device manager, so I can scan vehicle
r/CarHacking • u/Greedy-Pilot805 • 4d ago
Scan Tool OBD Scanner required ASAP! But which one?
Hi everyone,
I'm looking to purchase a used car privately and would like to use an OBD scanner that will help me detect mileage discrepancies and check that the VINs on the modules all match the cars actual VIN. This will hopefully help me from clone vehicles. But I can't seem to find the me that's suitable that I can get on Amazon next day delivery or a store in the UK. The only one I can find is CARLY but they don't have next day delivery and not available next day delivery on Amazon either.
I require a scanner such as Carly, OBDEleven, etc that have a small scanner, and an app. The reason is that I'm not sure how to use the complex scanners that mechanics and diagnostics use. Is there anything that can help me?
r/CarHacking • u/Ok-Tangerine-6775 • 5d ago
CAN Help with UDS bench testing MK7 Golf R Cluster.
Hello everyone, I have recently been diving into the UDS part of my cluster. I only have the cluster as of now, (im a teenager i only have so much money ;-;) and I have somewhat been able to get uds to work. That was 3 days ago, the UDS now doesnt work. I need to know exactly what every pin is for, to find a solution to this, as I am also trying to emulate a J533 on a arduino paired with a MCP2515. Any help would be appreciated, thank you!
Pins I already know:
Pin 1, 12v +
Pin 10, Ground
Pin 17, Can L
Pin 18, Can H