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en:can [2023/02/04 22:00] obd_diagnose Automatic translation |
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Example of a 500kBit/s high-speed CAN with 11-bit ID (CAN 2.0A) on an engine control unit: | Example of a 500kBit/s high-speed CAN with 11-bit ID (CAN 2.0A) on an engine control unit: | ||
- | {{ can-signal.jpg? | + | {{:can-signal.jpg? |
As you can see, CAN-H and CAN-L are in phase opposition. The advantage is that this eliminates common-mode interference: | As you can see, CAN-H and CAN-L are in phase opposition. The advantage is that this eliminates common-mode interference: | ||
- | {{ can-signal-detail.jpg? | + | {{:can-signal-detail.jpg? |
- | Usually there are several CAN buses in the vehicle, e.g. CAN drive, CAN comfort and CAN infotainment, | + | Usually there are several CAN buses in the vehicle, e.g. CAN drive, CAN comfort and CAN infotainment, |
In some vehicles (Ford models), e.g. CAN drive is also directly connected to the [[obd-2]] socket. | In some vehicles (Ford models), e.g. CAN drive is also directly connected to the [[obd-2]] socket. | ||
- | A popular physical connection for CAN is also [[cia-ds102-1]] . | + | A popular physical connection for CAN is also [[cia-ds102-1]]. |
Example of recorded CAN messages (CAN bus sniffing) with Kaufmann Automotive GmbH KCANMonitor: | Example of recorded CAN messages (CAN bus sniffing) with Kaufmann Automotive GmbH KCANMonitor: | ||
- | {{ kcanmonitor.png? | + | {{:kcanmonitor.png? |
- | Depending on the speed and bus load of the respective CAN bus, a very large number of messages can accumulate that have to be processed on the bus during " | + | Depending on the speed and bus load of the respective CAN bus, a very large number of messages can accumulate that have to be processed on the bus during " |
- | CAN is used for on-board diagnostics in most vehicles from 2008 onwards with [[obd-2]] . | + | CAN is used for on-board diagnostics in most vehicles from 2008 onwards with [[obd-2]] |
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+ | At least two nodes must be used for communication on a CAN bus. Since a sent message must be acknowledged by a receiver in the ACK bit, the sending controller sends out an error flag if the message was not properly ACK-checked. | ||
Links to the topic: | Links to the topic: | ||
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[[https:// | [[https:// | ||
- | [[https:// | + | [[https:// |
+ | |||
+ | [[https:// | ||
- | [[https://deloptes.org/wiki/index.php? | + | [[https://www.ti.com/lit/an/ |