what can cause an intermittent calendar error?

[slugger_dan]

I recently got a cheap 4slot with a calendar error. That's all that seems to be wrong though because sometimes it boots into crosshatch successfully. Most of the time though I get stuck on green screen or it just displays calendar error. I replaced the original battery with a fresh one but it did the same behaviour before and after.

I searched and causes of this include 32khz crystal not working or the calendar chip itself not working. I don't really know how to figure out something that happens randomly though, what could be the culprit for a calendar buggde board that doesn't always show an error?

 

[Xian Xi]

Usually it's due to corrosion or a bad trace from the 32khz crystal. Check the traces around it and even change the crystal if you see absolutely nothing.

 

[channelmaniac]

Or a corroded trace around the battery that supplies power to the D4990 clock/calendar chip.

That chip is powered by +5v when the system is on or by battery power when it is off. If that power trace is corroded you'll get that error.

 

[chris1]

I learn something everyday...

Thank you..