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Random jumping date/time on 4x Powerbook 160/165 - faulty RTC ?
Posted by: nvdeynde on 2017-12-27 12:19:30
I have a weird issue with 4 of my Powerbooks 160 and 165: I can't set the time and date anymore.

As soon as I leave the date/time Control panel, the date/time immediately jumps around randomly.

It may jump ahead half an hour, jump ahead a week, jump behind by 50 years, you name it.

Each time an application is opened or you for example double click on your Hard drive icon the date and time changes randomly.

These powerbooks have a rebuild main battery and also replaced Pram battery: both of these test well.

I have reset the PRAM by leaving it without Power for 10 minutes and then holding down both reset and interrupt buttons for 60 seconds to no avail.

I guess the Real time clock is not longer working. 
It's not a virus or software issue as even booting from a floppy disk with OS 7.5 shows the same problem.
Replacing just the logic board and it's fixed. However I don't have any spare boards left. 

My hopes aren't great this still can be fixed. Any idea's ?
I can't spot the RTC chip on the logic board, anyone knows where it's located ?

Posted by: benran on 2018-01-13 12:02:36
I have the same problem and its first time it has happened. Could it be a fault capacitor somewhere?

I´m rebuilding a PB 100 that has many faulty capacitor. I haven't seen a foto of the board yet.

Posted by: techknight on 2018-01-13 16:35:42
If I am not mistaken, I think the RTC is built into the same IC as the ADB, and possibly keyboard controller. But I am not sure on that one. 

Usually though when data is jumping around like that, its noise on the bus, which would put the RTC as a separate IC. So its confusing to think about. 

But my thought is the IC is going defective. Heating or cooling the IC may correct the problem temporarily and will snuff out if thats it. 

Posted by: MikeatOSX on 2018-01-17 15:19:58
I solved the same date/time problem on my PB 180c by replacing the interconnect board. 

Additional bonus: some dead keys are also working again. 

Posted by: MikeatOSX on 2021-01-18 11:54:54
See this thread too:

https://68kmla.org/forums/topic/48434-datetime-jumping-around-on-powerbook-160165/?tab=comments#comment-509222

Posted by: MikeatOSX on 2021-01-18 11:55:07
sorry double post

Posted by: MikeatOSX on 2021-01-18 11:55:33
third same post! 

problem on iphone...

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