Whelen Traffic Advisor TAL65 issue

[StEaLtH2]

Greetings, I have a TAL65 5mm Traffic Advisor that is acting up. One of the modules will intermittently stay lit, the issue comes and goes, right now its on steady even with the controller in the off position. Have inspected harness at the light stick and controller and all connections are intact. Any advice?

 

[MtnMan]

It's either a problem in the controller (most likely, in my experience), or the negative wire from that module is shorting to ground somewhere. You could disconnect the negative for the problem module at the controller to determine for sure. Here's the relevant manual: https://www.whelen.com/install/137/13761.pdf