Talon SRX doesn't seem to work

My team just bought 4 new Talon SRXs and one of them is not showing up on the roboRIO web configuration dashboard. All of the talons are wired up in CAN and 3 of the 4 are blinking orange when the robot is disabled, however, the one that is not working is blinking red.

I also tried connecting the talon via PWM but to no luck. Does anyone have any suggestions?

I would suggest checking blink code table in the Talon SRX User Guide.

We had a similar issue where our Talons would occasionally toggle to Red blinking for a few seconds during normal operation or when the robot was disabled. As it turned out, we had a loose connection in our CAN line from a poor soldering job that caused it to disconnect every now and again.

Did you have all 4 Talon SRXs hooked up and daisy chained together and only that 1 is blinking red or was it only 1 at a time testing and only that 1 was blinking red during the test?

Did you configure the IDs and updated the firmware?

Yes, they were all hooked up and daisy chained together. Only 1 was blinking red while the others were blinking orange when the robot was turned on and not enabled.

Yes, I configured the IDs for the three talons that were showing up in the web config.

I looked at the user guide and it looks like the talon is “not detecting the CAN bus/PWM.” We even tried switching the CAN leads with the other pair on the talon and are certain that its not a wiring issue. We used a multimeter to test resistance through the ends of the CAN wires in the daisy chain.

Hook each talon srx up individually set them to an open talon id and update the firmware, i think the problem is that the ids might be conflicting because you said you only changed the 3 talons you can see so the forth 1 might be the problem. Also if you hook up the one talon srx and there is still no talon identified i would recommend contacting cross the road electronics.

Do you have your CAN bus built like the image below?

If so, make sure you have the terminating resistor jumper set to the on position.

There is an installer you have to run on the roboRIO to utilize the Talon SRXs with the new firmware that came out this season. It can be found here.

Thanks DPolkowski, the diagram for the wiring helped out a lot! We had wired it so one end of the daisy chain was not terminated, or connecting to anything. We updated to the wiring in the diagram and the lights are now all flashing orange.

A high-speed serial bus like CAN shows some unobvious behavior when connection requirements like termination are not met. The device displaying the problem is often the one farthest from the faulty connection. Was that the case here?