I changed the battery on my X33 Skywalker: got some unusual display initially.

Blackdog · Sep 30, 2021

Last night I replaced the battery in my Speedmaster Skywalker.
Pretty straightforward actually. I did it with the crown pulled to the standby position (all hands at 12, display off).

The thing that surprised me a bit was that after installing the new battery the hands started ticking away and the digital display showed something unusual. It said OPEN or CLOSE on the top line, depending on the position of the crown (Standby/Normal) and COSC on the bottom line. I have not seen this mentioned in any of the tutorials I found (though most are related to Gen1/Gen2 of the X33).

I thought that the watch needed some kind of esoteric reset sequence, but just a push on the crown put it back in normal operation, so nothing to be concerned about, I hope.

I’m curious now, specially considering the COSC text: Was it some kind of self-test ? Diagnostic mode maybe ?
@Archer ?

Archer · Sep 30, 2021

Blackdog
Last night I replaced the battery in my Speedmaster Skywalker.
Pretty straightforward actually. I did it with the crown pulled to the standby position (all hands at 12, display off).

The thing that surprised me a bit was that after installing the new battery the hands started ticking away and the digital display showed something unusual. It said OPEN or CLOSE on the top line, depending on the position of the crown (Standby/Normal) and COSC on the bottom line. I have not seen this mentioned in any of the tutorials I found (though most are related to Gen1/Gen2 of the X33).

I thought that the watch needed some kind of esoteric reset sequence, but just a push on the crown put it back in normal operation, so nothing to be concerned about, I hope.

I’m curious now, specially considering the COSC text: Was it some kind of self-test ? Diagnostic mode maybe ?
@Archer ?

That would be a Cal. 5619, and I don't see anything in the tech guide that indicates OPEN or CLOSE is one of the messages that are normally seen, so no idea what that was.

Canuck · Sep 30, 2021

I don’t understand solid state electronic watches. But I have heard that, if the battery in your modern car is disconnected for more than a minute or so, once the battery is reconnected, it can take a few minutes for the computers to “re-learn” their programs. Strange things can happen. I have heard about “volatile” and “non-volatile” memory, and if a computer in a car has a volatile memory, it must be re-programmed after re-connection. Could be the circuits were re-learning, in your watch.

Blackdog · Sep 30, 2021

Archer
That would be a Cal. 5619, and I don't see anything in the tech guide that indicates OPEN or CLOSE is one of the messages that are normally seen, so no idea what that was.

Interesting...
Yeah, the OPEN/CLOSE was linked to the position of the crown (normal/standby), which I actuated because I was not expecting the seconds hand to start ticking with the crown fully pulled out... That is why I'm guessing some kind of diagnostics mode...
The COSC text was fixed. Anyway, it all disappeared when I pushed the crown, before I could try actuating any other button...

I managed to do the battery change cleanly, without marring any of the screw heads... I'm not really inclined to remove the battery again to test this any further... But maybe in two years I will...