[Knowme2k]

Hello everybody,

I am looking for a device with which I can diagnose ecus (specially BMW) on a workbench. Best with ICOM access. For example for speedometer / combi-instrument, navigation (CCC / CIC)

Thanks in advance for your help.

Best regards.

[egyclick]

Hello, an Inpa KDCAN cable will do just fine.

[Knowme2k]

Nope, i will do diagnostics/flash outside the car.

[egyclick]

In first post you said
"I am looking for a device with which I can diagnose ecus"

with an Inpa KDCAN you are able to diagnose module just fine on workbench as long as they are wired up correctly, in many cases you will need junction box (gateway) to be able to access different modules besides DME or DDE.

Flashing CIC for example does require ICOM ABC so in that case go for ICOM.

regards!

[Enabled]

Exactly. CAN H and CAN L must have proper resistance between the 2. 60 ohm total, usually built by 2x 120 ohm resistors in parallel on terminal ends, for long wires... but I read that on short wires, you can just use a single 60 ohm, but technically not correct.

[Node]

Technical explanation for resistor (if anyone is interested, somewhat simplified):

Technically resistors on end of wires are required to attenuate signal which gets reflected back. The reflected signal is what limits the data rate on the line because reflected signal interferes with incoming (you can call that capacitance). On long lines you need to attenuate it on both ends. On short ones however signal propagation delay is quite short so you can afford it bouncing twice before being attenuated. Please note that short/long are somewhat related to signal propagation time and data rate ratio, not some fixed length.

So it is technically correct to use one resistor on known short wires.