VAXstation 4000/90A suddenly show all led on.

[MattisLind]

I just tried to boot the 4000/90A that I have and it refused. It showed all led on. It used to work half a year ago.

Switched PSU from another machine - no difference.

Removed CMOS battery backed memory - no differenence.

What else can be the problem?
Would a depleted CMOS memory battery cause this type of problem?

 

[Schroeder]

Please use my response with caution, I'm in Sweden right now with no access to my 90a. What I remember is, that the batterie did cause issues. I had to replace it. I also had to reseat the memory. Beside all this, I had a burned pin on the power supply connector.

 

[MattisLind]

Aha. In Sweden today. I guess you weren’t near Strängnäs. In that case you could have helped me fault-find it person. I was showing Dalby Datormuseum for some visitors and the VAXStation refused completely. I had a /90 without A as well that started up happily.

Battery? As in the battery in the Dallas-chip (or is it ST?). You replaced the Dallas chip, right?

Didn’t check the power connector very much. Should do that next time.

 

[Schroeder]

I usually open the Dallas and add a battery holder.

I have a few but most 4000/60 with power connection issues. Not sure why.

Our house is near Älmhult, in the south of Sweden