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Climate control fan woes (a bit LONG)

A plea to the AC gurus on the list,

Any BTDT for the following on the 89 100 w/ Electronic Clim Control?
AC and fan work normal when car is first started in the morning.
Within several minutes of driving, fan fails and does not answer
call until left overnight.  Symptoms of fan failure is slow down on
low setting (hi setting works), then fan fails on both settings.
Outside air temps high 80s to low 90s F.

I have a text file of the channel codes that were pulled when fan works
and fails (did not attach to save bw, but can send via private email).

In summary (unless otherwise noted, codes were same regardless of fan
working or not) pulling the codes revealed:
Channel 1 
codes 05,09 - outside (behind radiator) and coolant temp sensors
circuits open (faulty).
Channels 5 and 6
outside and coolant temp sensors show graphic lines that look like 
right and top sides of a box with 55.
Channel 7
output signals from control panel head:
When AC/fan working        	When Fan not working
Rad fan 1st speed		same 
AC compressor on		same
Center vents full open		same
Center vents half open		same
Heater valve closed		same
Floor vents open		same
				Air recirc door closed
Channel 8 and 9
"Position of temp reg servo" (8) and "Specified position of tem reg
servo" (9) have same graphic of right and top of box with 39 on (8) and
48 on (9).  

Rest of codes seem OK, including blower motor voltages 12.4v on high,
6.1v on low and 0 high pressure shutoffs of compressor.

Compressor and relays can be heard engaging/disengaging to inputs from
from the clim ctrl buttons.  My only "guess" is the blower motor is
overheating and shutting down.  Any help is appreciated.
MJ Murphy