Freely programmable motor controllers

Hello, I'm trying to decode some messages from freely programmable motor controllers to use them in my engine test bench. However, I'm unable to establish a connection with the Canhack in my experimental setup on the table. With other USB to CAN devices, I only connect CAN High and Low, and I can see the data packets. I have set the transmission rate. I have connected High, Low, and Ground. Do I still need a 12V+ connection?

Happy Easter, Frank.

Good evening, Frank,

The CANhack only requires CAN high and CAN low signals for its operation.

It can't be because of that.


Have you integrated a terminating resistor into your experimental setup?


How many CAN participants does your experimental setup have?


Best regards,

Michael.

Hello Michael, thank you for your suggestion. There is resistance. It's only connected to the control unit with the Canhack interface, no other devices are involved. Could this be a problem?

Best regards, Frank.

Hello Frank,

Yes, that could be your problem.

Possibly. You need another participant.

It could also be another software tool through which the communication takes place.

Here's how I help myself when testing CAN gateways on the table. Here's a quick and easy way to check if messages you send are actually being received.


Is your control unit actively sending data on the bus?

An engine control unit (ECU) requires at least one wake-up signal or a cyclic ignition pulse in the form of a CAN message for communication to occur.



Good luck.


Michael.

Hello Michael, I haven't had any success yet. I've now connected another display, which is also working. I've tried it with and without a resistor. I know that the speed is 1 Mbps, and I've also entered that in the settings. What should be in the fields where "FFFFFFFF" is the default value? Can I leave it like this?
When I plug in the dongle, the LED turns green. However, when I click "connect," it turns red or orange. I suspect it's a user error.
I haven't found a suitable guide yet.

Thank you for your tips.

Best regards, Frank.

Hello Frank,

Regarding the software and ease of use, Rainer is clearly the better choice. And he probably has a good suggestion for setting up the test.

I'm not quite clear on your structure or your plan yet.

Question 1)
What exactly do you want to do or achieve?

Question 2.
What kind of "participant" are we talking about?

Question 3.
Do you have a second software program open so you can send a message from one program to the other and see if your setup and connections are fundamentally correct?

Question 4.
Do you perhaps have a saved trace that you can run to see if your participant is responding?


Question 5.
What does your adapter, which you built from OBD to CAN High and CAN Low, look like? Are the pins correct?

Best regards,

Michael.

Regarding question 1: The goal is to transmit data such as ignition timing or lambda values to the test bench. To do this, I would have to manually enter the data fields to be monitored into the test bench.

Regarding question 2: These are aftermarket engine control units (ECUs) from various manufacturers. In this case, it's a KMS that's lying on the table.

Let's mix questions 3, 4, and 5 together.
When the ignition is turned on, the control unit continuously transmits data, and the test bench software should then extract the relevant data and constantly update it on the monitor. I can observe this data stream by using a USB to CAN adapter from Ecumaster. Therefore, I know the transmission rate, which is 1 Mbps. I modified the adapter by taking it out of the included connector. Using pin 64. (they also have a connection to the dongle, which I check by holding the Ecumaster device there, and the data is immediately visible).
Okay, so my current problem is that I can't seem to get any data into the Canhack.

Best regards, Frank.

Hello Frank,

Thank you for the information. Now I have a better understanding.

You are writing pins 4 and 6...

Pin 4 & 6 from Canhack?


The Can High pin on the Canhack OBD is pin 6, and the Can Low pin is pin 14.

The pins on the Sub D connector are located at pin 2 for CAN High and pin 7 for CAN Low.

I'll check that out later.

It's almost ready to go...



Best regards,

Michael.

It should say 6 + 14, I have no idea how the smiley got there.
I pinned it based on the image from the package insert, and I assumed that was the front view.
Okay, so the diagram shows the location of the OBD2 port in the vehicle.

Hello Frank,

The view is from the front, looking at the OBD socket in the vehicle, meaning that pins 6 & 14 on the connector from the Canhack are located on the side opposite the LED, at the height of the second A from Kaufmann.

That would have determined the location of the pins. Does that match your pins?





Best regards,

Michael.

Hello Michael,
Then I have the right pin.

The speed of this device is like this. It's more geared towards motorsports and likely intended by the manufacturer to be used as an add-on for other products, rather than being integrated into a road vehicle. (For example, there's a wideband lambda CAN controller or an electronic throttle module.)
With other manufacturers, you can also adjust the speed.
If I have time tomorrow, I might try this with another engine control unit (ECU) manufacturer.

Hello Frank,

Okay, the pins are correct.

The LEDs also fit. Green - when connected to the PC, red when connected.

Have you ever tested the KCANMonitor software on a production vehicle to narrow down the source of the error?


Greetings.

Michael.

Hi Frank,

Are you sure you've identified the correct pins on the engine control unit? I sometimes accidentally plug things in backward (e.g., plugging a plug in from the back instead of the front).


Is the bitrate set correctly in KCANMonitor? The CAN bus speed is usually 500 kbit/s, but it must be the same as the setting in your control unit if it is adjustable. NO "list-only" mode if nothing else is connected.

Does your engine control unit support bus termination? If not, use a 120 Ohm resistor between CAN-L and CAN-H.

Most likely, the problem is either an incorrect bitrate or incorrect pin assignments.

Quote:

Have you ever tested the KCANMonitor software on a production vehicle to narrow down the source of the error?

When using KOBD2Check on a modern vehicle with OBD2 via CAN, no wires need to be tapped into.
The CAN transceiver is actually quite robust; it doesn't break down easily (or, more precisely, it hasn't failed even once so far).

Sure, here's the translation:

"LG" translates to "Best regards" or "Sincerely" in English.

Okay, today I'm just doing a quick test on a vehicle. It's a VW Sharan, manufactured in 2009, with a speed reading of 500,000, which is likely a standard value. Plug the connector into the socket, turn on the ignition, the LED on the connector turns green, press the Connect button, the LED turns red/orange.
Now the question: Should the data be arriving now, or am I missing something?

Thank you for your help.

Hello Frank,

If you connect to the OBD2 port and start KCANMonitor, you won't see anything. Tracing doesn't work here. You would need to, for example, put the control units into diagnostic mode, and then they would respond.

Or, as Rainer suggested, you can take the KOBDCheck. That's how it works.

With KOBDCheck, you can display certain parameters.


Best regards,

Michael.

Okay, thank you.
I will test it at the next opportunity.