Motor Vehicle Maintenance & Repair Stack Exchange
Motor Vehicle Maintenance & Repair Stack Exchange

Questions tagged [can-bus]

CAN (Controller Area Network) bus (internal vehicle communications network) is a message-based protocol, designed originally for automotive applications, but can now be found in aerospace and maritime as well. This is a standard which allows different parts within a vehicle to communicate with each other without the use of a host computer.

CAN (Controller Area Network) bus (internal vehicle communications network) is a connector to a message-based protocol network, designed originally for automotive applications, but can now be found in aerospace and maritime as well. This is a standard which allows different parts within a vehicle to communicate with each other without the use of a host computer.

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Difference between OBDII and CAN

What is CAN (controller area network)? What are the differences between an OBD-II protocol and a CAN setup?` How do I use an OBD-II scanner on a vehicle with CAN?
Shobin P
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Can a vehicle be harmed with bad inputs via an OBD-2 port?

I bought a cheap (sub $10) ELM 327 Bluetooth clone OBD-2 diagnostic adapter on a local "ebay-style" market where the seller specializes in car diagnostics and has several thousand positive reviews (read: I guess this seller would not provide…
Kozuch
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Why are there multiple CAN buses in vehicles?

There are a number of questions on the CAN bus but none (so far as I can tell) that explain why there are several CAN buses in a vehicle. From what I understand many different nodes can be connected to a single CAN bus, so I am not sure why you…
Moeman69
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How do I find the correct pins in a CAN-BUS connector?

This question might be too technical for this forum, but I'll give it a go. I have a 2012 BMW R1200R motorcycle with CAN-BUS. I'd like to make an Arduino interface to the connector on the bike, but I don't know the pin definitions... Do anyone know…
Eric Fossum
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Received frames from vehicles with multiple ECU chips

I'm not generally a 'car person', so hopefully I can explain this well enough to get some help here: When sending messages to an OBD-II device, I receive one response in most cars I've tested. However, with cars that apparently have more than one…
Rein
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Controlling door locks via CAN bus

I'm trying to figure out how to lock and unlock the doors of a 2010 Toyota RAV4 using the CAN bus via the OBD-II port. I have a microcontroller attached via an CAN controller and a CAN receiver, and I've written some firmware to capture and replay…
Isvara
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Controlling door lock/unlock via CAN bus

I'm trying to figure out how to lock and unlock the doors of a 2016 Mercedes Citan using the CAN bus via the OBD-II port. Is there some kind of OBD-II interface where I can control this with plain negative pulses? thanks
Sebastian Breit
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How is video transmitted in the car? (E.g., from backup camera to NAV display.)

Does video from the backup camera or side mirror camera travel to the (NAV) display via the CAN bus or some other mechanism? I'm really curious if you can get access in some way to that video - or replace it. (E.g., grab it from the bus and put it…
davidbak
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Computing Wheel Torque From Engine Torque

It seems possible to obtain engine torque and RPM from a truck CAN bus. I'd like to estimate tractive force at the wheels given these two values. How should I go about computing torque at the wheels? Wouldn't I need gear ratio, which doesn't seem…
user1889776
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ATMA on OBDII not Working

I have successfully connected a terminal android app to the obd port of my car. And tried dry run of many at commands, many are working as expected. But ATMA (AT command to Monitor All) is not responding. Trying to view all the can…
vinay
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Is it possible to auto close the power window of a car using OBD and CAN bus?

I am not an electrical or automobile engineer, so pardon my ignorance. I found this product in the market to auto close power windows for certain brands. How can we send signals to the CAN bus using an OBD interface? Does the automobile manufacturer…
rp1980
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Is there a way to use a PC as an ECU for testing CANBUS Sniffer devices?

Is there a way to connect CANBUS sniffer device to a PC (computer) with CAN-H and CAN-L pairs and test the sniffer device? I want to convert my PC to an ECU emulator, connect a CANBUS sniffer device's CAN-H and CAN-L cable pair directly to a PC's…
Sencer H.
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Is it possible to access multiple CAN buses through the OBD-II port?

As usual I apologize if this has been asked and answered somewhere. I try to only ask questions if I can't find an answer or a satisfactory answer. From my understanding the OBD-II port on vehicles is either connected to a dedicated gateway…
Moeman69
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OBD2 and CAN-bus

Do all vehicles with OBD2 have a CAN-bus? Otherwise, what are the alternative buses used? Are there special versions of the buses for trucks and school-buses than for cars/suv/vans?
Cynthia Avishegnath
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Writing CAN Messages

I want to know what should I write with the CAN ID to send it to ECU. I am using ELM327 and Raspberry Pi with all connections to OBD-II. Initially for sending general PIDs to the ECU through ELM327 and Raspberry Pi, I used '010C\r' for PID 010C.…
user3098378
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