Yet Another Keysight 3458a ERROR 202, “HARDWARE FAILURE – SLAVE TEST: DC BOARD”

[skjafar]

Hi all,

I had posted in Metrology  but I have not received any help. I was hoping maybe @TiN can provide some help.

Anyway I hope somebody here has some information.

I have the following error when the device does the self-test:
ERRSTR 202, “HARDWARE FAILURE – SLAVE TEST: DC BOARD”

No other errors reported.

No measurement is being made. Even TRIG didn't trigger a measurement.

We sent the device for service at Keysight, they asked for "only" $7.5k to replace the DC Board and A/D board plus a calibration. I didn't foresee such a bill. So I didn't do the repair. It's such a valuable device to sit as a paper-weight though. Please help me get it running again.

Here are the faults reported by Keysight:
Time out unable to read A/D. Cal value Out of Range "95"

Can anyone who knows this device explain what this means?

I found U2 on the DC board damaged, they relays were not running, after replacing it they are working again but the failure didn't clear.

Please note that this is a device I bought brand new around 2014 and it was never tampered with before this incident.

After injecting 1V through the terminals, I see 1V on both TP10 and TP11 but Q12 is off and it is not passing this voltage to P4. Q12 is controlled by a signal coming from the 8051 uC which is indeed disabling it. Does the system do this because it failed the self test? maybe as a safety feature?

Do you have suggestions?

[coromonadalix]

double posting is not permitted

[skjafar]

My bad, I was not able to remove the other post.

I think it's more suitable to post it here in "repair".

[Simon]

So give me a link to your other one and I will delete/move it for you.

[skjafar]

I've done some measurements around in the A/D board as well.

HTRIG is low, but that's because the RAMP signal is also zero volts. Then I checked TP404 which is giving me 0.4V, then check both analog switches on C408 and C409 they are shorted and the capacitors are not discharging.

Control pins TP401, TP402 TP403 are not changing, even when I do an AutoCal, screen shows sampling indicator blinking but HTRIG is not changing.