DSO-X 4154A not booting

[rtekal]

Hi,

I have a Agilent DSO-X 4154 A in which the display is not coming. I have monitored the voltages mentioned in the service manual. The VP25V (Backlight power) and the (VP13VPRB Auto probe power) are not coming. The front panel lights of Ref, Math & Digital glow sequentially and stops there.

I tried analyzing the power up process and found that the NCP3064 pin 5 on/off is held low. I am unable to find out the source for this control pin.

Anyone who has faced and resolved this problem, please help. I have 2 more MSO's with the same issue.

I read in the other forums that Keysight has a service note 3 for this problem, but Keysight has removed that service note.

Regards

[Pinkus]

as said in the other thread twice: you must log the output of the serial interface. Everything else is just guessing.

[rtekal]

as said in the other thread twice: you must log the output of the serial interface. Everything else is just guessing.

No offence meant. Just posted it here based on your reply to my post in the repair thread.

Will post the serial data once I get back to the dso.

Regards

[Petter]

I had a similar (your description is a bit too vague to say for sure) boot problem with a DSOX3K. Turned out there was a free repair for that - it was caused by dodgy memory chips causing a boot problem. Later firmwares are more tolerant to this issue. There was some activity of lights on the buttons, but no display. Might be the same problem for your scope. Good luck