Nest No Power Error - Its worked fine for the last year

[catsi]

The nest was installed over a year ago and we havent had any issues with it. 

Today it went off the wifi and then when I checked the device it originally gave me an E298 no power error. I've been working and havent had a chance to look at it. I just reset it (its been about two hours) and now its giving me Undetected Wires Y-C-W-G-R-*OB, E298, and M20 errors. Still wont connect to the wifi

what could be causing this? 

[CoolingWizard]

@catsi ,

You need to get a Volt Ohm Meter and check the power.  Setting the meter on AC Voltage, you measure between R and C wires and the voltage should be 24VAC, +/- 5VAC.  If you have voltage there, then the problem is the thermostat.  If there is no or very little power, then the problem is in the HVAC equipment. 

AC Cooling Wizard