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The answer depends upon what sonar transponder you have (by maker and model), and what radar transponder also. Please tell me, and I will research the matter and let you know the result.
The 'thermal vision' is so unusual - most setups don't have it - that, if it is hooked up to the Garmin GPSMAP, I would need to know its maker and model # ***** Unless its connection is simply NMEA XXXX or similar, in which case just knowing its communication protocol would be enough for me to judge.