If you are asked to send diagnostic data from HMC
First you have to login to HMC as "hscpe" user (SSH session using Putty)
Then run program which will create *.zip file
pedbg -c -q 4
Zip file you can find in /dump directory
ls /dump
File from HMC can be downloaded using Putty application on Windows
"C:\Program Files\PuTTY\pscp" -scp hmcuser@hmcserver:/dump/HMClogs.xxxxfilexxxx.zip C:\Directory\
*.zip file on HMC can be deleted using this command
pedbg -r /dump/HMClogs.xxxxfilexxxx.zip