J1939 DD_Rx troubleshooting

[rschultz]

I am trying to receive the fuel level signal from a truck engine and display it on a DP600. I am using the DD_Rx function block. My problem is that the signal out of the block is “pulsing” on and off.
It’s on for a second. Then off. Then right back on for a second.

Anyone have any ideas what might be the issue?

I can provide more details if needed, but had to make this post short due to being on my phone

[FluidPowerTom]

Is the actual CAN message data bouncing between the correct value and zero?  Are you able to monitor the bus and find that message to verify?  If the data is solid then there's something in the programming.  Those compliance blocks should be rock solid.  Maybe the message is only sent every second or so, and somehow the program is zeroing it out when it doesn't see the message for a while.