Gestetner DSm615 giving error SC:552,How do i clear it

Are you sure of the code? I don't have the exact manual for that, machine but the number seems strange. "5xx" errors are usually related to the fuser, so could be a bad lamp, thermistor, or fuse. see note to reset (if there is not a problem) as follows:
There are 2 levels of service call conditions.
Level Definition Reset Procedure
"A"
To prevent the machine from being
damaged, the SC can only be reset by a
service representative.
The copier cannot be operated at all.
Enter SP 5-810 (SC code reset) and
select “1”. Then hold down the Original
type key and the OK or ! key at the
same time (this does not require the
main switch to be turned off and on).

Yes, mine were successfully RESET from the error code SC:552 and SC:302. Machines runs good, but i about to wander what could be faulty inside, it took one month after error code 302 exist. Mine was exactly DSM615 same model same error code 302 (this is really 302) which resolved by reset. Hopefully machine will run good for two months.
To RESET it
1. Press Yellow button
2. Press 1, 0, 7
3. Hold Orange button for 3 seconds
4. Select MODE 5
5. Select Clear Memory (or something like it) (801)
6. Select 002-Engine
7. Select EXECUTE
8. Turn the switch off and leave it for a minute
9. Turn back machine On.
10. Done, or else there could possibly something else.

Good Luck....
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