Heater Running But Thermostat Went Blank -- Help Please!

[ehang]

My honeywell wifi thermostat went blank while my heater was running yesterday and now I can't shut off the heater unless I unplug the York furnace. Here's what I've checked so far but still can't figure out what's wrong and the cause of my blank thermostat. Would appreciate if anyone can give their expertise and suggestions, thank you in advance.

1. Changed battery on thermostat (it's powered by c-wire but changed battery just in case).
2. Used multimeter to get a low voltage VAC reading from the wall where my thermostat is installed - no voltage detected.
3. Checked circuit breakers. Not tripped. Checked voltage at breakers, confirmed breakers are working fine.
4. Checked fuse inside furnace - fuse is fine, not blown.
5. Checked furnace transformer. 120v coming in fine and there are two low voltage leads going out. One had 24v reading (#1 in picture) and the other had 0v reading (#2 in picture). Did not do a resistance test.
6. York furnace light blinking green at intervals of four.
7. Checked low voltage wiring leads on furnace board (wires that go to the thermostat, outlined in red in picture) -- no voltage on any of the leads. (heater was turned on and running at this time)

Tempted to just replace the transformer but concerned it might go out again if something is wrong with the system. Also tempted to just put in a new fuse (even though it looks fine) or resort to replacing the thermostat but it's only 4 years old and if I'm not getting power at the thermostat wall, highly doubt the thermostat is the issue.

Appreciate any/all help, thank you so much!

[slctech]

Yeahhhhhhhh, you really might want to re-read the large RED description of this particular forum...NO DIY advice will be given. Thus we can not assist you here. There are DIY sites elsewhere that may be able to offer you some help or assistance other than that all we can suggest is call in a technician.

[HeyBob]

Sorry, this is not a DIY site, please call a contractor.