Electrolux washing machine not reaching temps

[schreib]

I own an out  of warranty, by a few months, EFLS617STT washer and wife does not feel it is hitting temps on HOT.  So, I hung a thermocouple in the tub while running through cycles and sure enough, sanitize seemed to hit target temp( around 152°F) but hot and cold were DEAD cold.  Called a "certified" technician approved by Electrolux and paid $95 to hear her tell me the inlet solenoid valves are the problem.  I could pay another $220 and have them actually DO something and replace the valves.   THAT seemed a bit much!  So, believing her, I just ordered the valve assembly off eBay for $25 shipped to my door and PLAN to replace them. . . However, thinking further, it seems to me some sort of temp sensor must be responsible for the boost heater not sufficiently re-heating to the required temp the machine is asking for.  My hot water supply is set to 128°F and is less than 10 ft away.  The fact that sanitize seems to hit temp is confusing though.  

 

-- If the system "works" for sanitize why not ALL three temp levels??

-- Is it possible that the temp sensor is part of the valve assembly?  Wiring diagram appears to indicate the NTC(?) is with the heating element. . .

-- Is it possible the main board is simply not controlling temps correctly and needs replacement.

 

I cannot find ANY other control parts on the diagram that are likely suspects.  Ideas??!  thanks.