all it needs is a new NV ram battery. (just did this hours ago for same reason,)
the book is clear, it says and I simplify, if CKsum fails, ignore all other errors !!! (that is because all amp offsets are lost and all self tests will fail)
all 2430s do this and is a simple fix,
replace the battery Keeper-II (early models, like mine is)
or if no keeper bat there. (last models are)2430a , replace the Dallas Nvrams DS-nnnnn SRAM, they have a battery inside. I'm told some version have 2 Dallas NVram there, (look carefully for dallas)
then remove the J156 jumper
do not run with case off, or use external fan to a10 board bottom or it will BURN UP,
let the scope warm up for 10 minutes, the screen tells you that its not warm , wait for it ... then.....
do the full diag (chapter 5-10 to 12 covers this the book is free from tek, need links?)
then do the calibrate.
last do the external CAL. using only an accurate PSU, variable power-supply, and good DMM 4-1/2 digits, (our meter today exceeds the old PG506 level gen by tekl. by 10 fold)
I used a 10k ohm and 200ohm , low PPM resister pair (divider) to my 20vdc bench supply. (adjustable from 0 to 20v)
then I did the external cal.
levels. do the 3 dc levels as prompted. see it pass. ch1 and ch1 connected to source
triggers, do the 3 dc levels ext, trig 1 and both same time.
repete (needs no inputs) its a all automatic.
then when all 3 say passed.
turn off scope see chksum pass. on next power up.
the remove J156.
done.
that halting is normal, it goes to cold start when CKsum fails for good reasons, not to do damage. with cal tables lost.
on mine +5vd bus rail shored and I lost all cals.
ribbon cable was cut by case, pin 1, +5vd, cure that and the blow fuse, and it cals prefectly. 32 years old running strong.
as with any electronics
we check all supplies first for spec voltages and out of spec ripple. first.
end 2340s , that all fail this way. all do and is not big deal at all.