change the boot mode to show “01 B N V=F”
On most hardware the operator panel buttons are as follows (v) down, (->)enter, (^) up
Do this by using the up/down buttons to go to 02 (menu 02) then hit the enter (return arrow). Use the up/down to change the first field to B, then hit enter, change the second field to N, hit enter, make sure it has an F instead of an S (fast boot vs slow boot mode). Then hit enter once or twice more and you will be back to just the 02 menu entry, arrow back to 01 and hit enter to verify your settings and then hit the power button.
You can also change the IPL source at powerdown by using the F4 key with the pwrdwnsys command. This in addition with CHGIPLA will allow you to set the way the system will IPL under normal conditions. You can see your IPL settings using DSPIPLA
Control Panel Functions: