Thermostat Display Problems

I have two Honeywell T8601 thermostats in the house, one upstairs and one downstairs. The floors both have separate blower and a/c units. Last night I pressed the info button on the upstairs thermostat and the display went blank. I checked the fuse box and nothing has been thrown. I swapped out the downstairs thermostat with the one from upstairs and it displayed fine. The therm. taken from downstairs would not display upstairs. So, it's not an issue with the thermostat itself.
Any thoughts on if the cause could be in the components on the mounting plate or at the a/c unit or blower? If so, any suggestions on how to isolate the problem?
Thanks in advance.
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Do a google search... this EXACT same question has been asked before.
Almost "Word for Word".
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We had a water heater replaced a few weeks ago up in the attic where the blower is. I took a look at the wires going into the blower unit and found that the one from the outside A/C unit was pinched and the insulation on the wires was stripped off which probably happened when the installers squeezed the new water heater up into the attic. Could be related but I wonder why the thermostat not displaying would be related to the wiring between the blower and the outside a/c unit.
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On 21 Mar 2007 18:40:47 -0700, parker snipped-for-privacy@yahoo.com wrote:

Dont be confused. It IS the thermostat. It's almost always the thermostat. Change it and you will see the difference. Change the low voltage wiring too with matching 18ga 8 wire for proper electron flow. Bubba
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