Author Topic: CAN troubleshooting issue  (Read 19845 times)

cesarcontrollers

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CAN troubleshooting issue
« on: January 13, 2014, 05:45:04 PM »

At this point I have an issue with CAN that works with J1939.
There are some compoments within the network that are "offline"
I can see them on the machine's display.
There are 3 different ECUs that seem to work right, and it could be a wiring issue but nothing wrong with the wiring, and the termination resistors has been found so far. They are in the right resistance parameters and voltage signal seems to be right as well.
Not sure what else I could check? The controllers are MC05010, and also the machine has two IX024010

Thanks

Any help on this will be appreciated

Offline BRIan

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Re: CAN troubleshooting issue
« Reply #1 on: January 13, 2014, 10:15:23 PM »
Has it ever worked correctly? Have you changed anything recently? Do all the nodes have differing IDs? Have you tried using CAN king to view CAN traffic? Are any of the devices CANopen? Are all the baud rates the same? What nodes are "missing"? Are they only misssing on the service tool? Is the service tool connecting?

cesarcontrollers

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Re: CAN troubleshooting issue
« Reply #2 on: January 14, 2014, 04:29:41 PM »
BRIan,

Firstly, thanks much for your reply.
let me give you a brief description of this CAN issue:
The CAN network was working well until the alternator belt of the JD engine broke.
After the belt was changed, the trouble started. At this point the JD engine ECU, two module expanders and two other ECUs are offline. (these are the nodes as they work under J1939 protocol to my knowledge). On the display (DP 200) this machine has all of them appear ''Offline". 
I tried to plug with the P1D file but as they are offline I could not make it. So, I don't know what might be going on with baud rates and stuff, but not sure if there could be another way to check it? the service tool is not connecting. No, I have not used CAN king so far.

Thanks much

Offline BRIan

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Re: CAN troubleshooting issue
« Reply #3 on: January 15, 2014, 04:41:15 AM »
Assuming the following has already been covered:
Power on, CG150 installed correctly, USB port configured correctly, wiring correct pins used and not swopped, terminating resister(s) OK, baud rate on the service tool set correctly, service tool is set to online, all nodes are broadcasting at the same baud rate, lines are not too long for the baud rate used, all nodes have a differing number.
If still not communicating, then disconnect all nodes except for one and check comms again. Do this for each node individually. If all OK individually, reintroduce each node one at a time until comms is lost.

cesarcontrollers

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Re: CAN troubleshooting issue
« Reply #4 on: January 15, 2014, 03:22:54 PM »
Right, thanks for your reply. comms, I think you refer to communication right? if the comms is lost after doing the process you describe, what it would tell me?

Thanks much,

Offline BRIan

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Re: CAN troubleshooting issue
« Reply #5 on: January 15, 2014, 10:22:43 PM »
Yes comms is comunications. If the communications set up is correct but you can not communicate with any or all of the nodes, then it would appear that there is a hardware fault with that node. To rule out a possible communications set up problem, you should connect a known good piece of hardware to confirm the green "Connected" icon shows up at least once.
Are you a user or developer?

cesarcontrollers

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Re: CAN troubleshooting issue
« Reply #6 on: January 16, 2014, 03:56:31 PM »
Right, thank you. A harward fault could be something related to a wiring issue?
I' m an user.

Thanks for your help,

Offline BRIan

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Re: CAN troubleshooting issue
« Reply #7 on: January 16, 2014, 10:41:01 PM »
Talk to the people who supplied the hardware/machine, they should be helping you.
have you tested the nodes one by one? Have you found some that work and some that don't?
A voltage spike > 24V could trash the CAN chip. Normally of course these wires should not be able to see the supply volts.

cesarcontrollers

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Re: CAN troubleshooting issue
« Reply #8 on: January 16, 2014, 10:48:34 PM »
Yes, I have been talking to them. However, I'm trying to consult or get some more tech info on this on my own. No, the nodes have not been tested so far but they will.

Right, thanks for your info and help, I'll let you know how it goes. are you a developer right?

Offline pinias

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Re: CAN troubleshooting issue
« Reply #9 on: February 20, 2014, 10:54:54 PM »
Cesarcontrollers,

you may have already fix your issue however I just want to share a common mistake I have found and some basic rules I have set for me and the crew that I use to work with.

1.- the CAN does not work, .- most of the times the wires are in short or they tied CAN0 with CAN1.

2.- Never asume pin3 is CAN0 high and pin4 is CAN 0 Low.   it is different for the DP600 that is CAN1 instead of CAN0 in other words check the datasheet always
3.- It was working but now I does not work any more.
      if it was working fine and then it suddenly stop working, the problem is hardware, maybe a wire was damage, if using terminals connectors the wire came loose, the resistor got broken (depends on how it is wired).
      Last thing to try is a different device.
   
   Personally if it have worked at least one time as expected and then fails you  got a hardware issue. NEVER start trying to modfy your firmware your issue will get even worst

4.- My CAN bus is fine, all is connected propery however it does not work and I got the red LED blinking at my DP600.

posible issues: The baud rates are different (passive error).
WHen there is an I/O module in the CAN and you are sure about the baud rate of the devices , the issue may be:the wires of the I/O module are reversed.

I hope this helps you to do a troubleshooting when needed.

Antonio