Keithley 2304A displays dashes instead of measurements

[jgorsk]

I have a Keithley 2304A power supply that displays dashes instead of the measurements.
The output works fine.

I reset the settings to default, no difference.

Is there a setting that can cause all the measurements including the DVM reading
to display dashes instead of the actual measurements or is it a hardware fault?

[macboy]

Based only on my experience with several other Keithley instruments, the "--------" display is the result of measurements not being triggered. Most people are accustomed to meters just measuring all the time, but all of my various Keithley meters require setting up a trigger. This can be set to "continuous" to get the usual behavior.

[jgorsk]

I tried to change the trigger settings, but no change.

What would be the settings to get the continuous triggering of the measurements?

It's not only the current, the output voltage and the DVM readings are showing dashes.
Applying a pulsed load also doesn't result in showing any measured value.

[macboy]

If you are certain you have done everything right, but you still see no readings, then you may have a fault.
I had a quick look and didn't find a service manual other than one for a 2303, which is in the same family. Unfortunately, that one has only a parts list, with no schematics, no troubleshooting information, no theory of operation or block diagrams. So basically, you are left to figure it out yourself.

I am in a similar situation with a 2400 Source Meter. It has a fault which I don't think is serious but haven't yet identified. Its service manual has no schematics, but does have some block diagrams, theory, and limited troubleshooting information. It's not enough but it is something.

[jgorsk]

It looks like the unit is faulty and the measurements don't work.

I tried calibrating the PSU and it just hangs when it tries to measure the output voltage
in the first step of the calibration.

Similar ADC is used on the 2000 multimeter
https://doc.xdevs.com/doc/Keithley/2000/K2000.pdf

Someone did a great job drawing the schematic. Thank you.