Hi, I'm sorry to hear that. Have you ever gotten heading from that setup?
This sounds really like a bad sensor or if it isn't hooked up correctly, I would check there to be sure though.
The head units are almost never the problem when you aren't getting any data, that is more than likely a bad sensor.
Also in answer to your question initially no there is not a sensor internal to the head unit.
In any case, I will stick with you until this is complete.
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