York ycaj77 problem

[PLEH2EREH]

The chiller will operate just fine for a couple of days, even a week, but at times it will be found not running and the display will be blank. When this happens, it has to be reset and the program "set-points" have to be reentered. The clock (battery backup) has already been replaced.

[Onsyi]

I had a similar situation, the reason was to fuse holder, the unit was only YAES1075SA, due to laxity nest door reverses power is lost, or at any vibration.
And maybe we should consider the option of diversion?

[PLEH2EREH]

Very little vibration at control panel. Doubt that it would be the fuse holder due to the display backlight still illuminated, just no information being displayed. With the new clock chip, which is the battery backup, the program should not be lost, but I have to reenter it. The mother board and power supply has already been replaced as well. When found in this condition, there is power to the display, but the +5vdc on pins 1 & 2 of the ribbon cable is not present. This was checked at the display and at the other end of the ribbon cable (on the mother board). So something in the mother board is preventing this. But like I said, the mother board was replaced by another technician.

[al]

Check all legs of EEPROM are inserted properly, possible when changing boards that one pin is missed, was EEPROM replaced at same time, if not worth swapping it just in case.

[PLEH2EREH]

I was told the mother board was changed along with the power supply. The EEPROM was replaced at that time but it was a stored item and possibly bad due to shelf life of several years. New one was ordered from factory and replaced. The main power source (480 v disconnect) can be opened and reclosed and all program memory stayed intact. However, whenever the unit decides to die the memory "program" is lost. It has been noticed on the prior mother board and now this board that to the right of the EEPROM on the board itself there is a discoloration, sorta like as if it smoked (a slight grayish/white figuration). I don't remember right off hand but there is a ribbon cable (P2?) coming from the power supply down to the mother board and when the display is blank this cable can be unplugged and then plugged back in and there ya go,, the display comes back. The bad part is, the unit will start back up and then all one can do is wait till it happens again..

[PLEH2EREH]

Would also like to add one more item. Yesterday I checked history and it actually indicated a shutdown on low suction. The neat thing is it indicated it was on a date way in the past! I just reset the date and time last week. So I went in and to reprogram the date a time and entered all however, it wouldn't change the actual day. It kept displaying Sunday for Monday's date. Didn't have time to check on this issue but will when I attack it again tomorrow, which is now today!!

[PLEH2EREH]

Figured out how to set the date right. Unit still running.....waiting...