Loss of signal in the SYNC Sat Nav system can be caused by a variety of factors, such as poor GPS signal reception due to tall buildings, tunnels, or weather conditions. One of the first steps in troubleshooting this issue would be to check the GPS antenna and wiring to ensure that they are properly connected and not damaged.
One possible cause of the issue could be related to the software or firmware of the SYNC system. In this case, it may be necessary to perform a software update to fix any bugs or glitches in the system.
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