What Could Be The Failing Component On My Machine With Displays SC: 552 With An Error Message "Turn Off Main Switch And Then On" ?

Dirty fusing thermistor. Clean it, go into tech mode and turn off main power switch to reset it.

press the up/down arrows together for @ 5 seconds, then hit "ok".
scroll to "engine"
look for 5-810 -SC reset, hit "OK" turn machine off/on using toggle switch.

found this solution on line -Ricoh Copier Error Code SC 552 is Fusing thermistor error 2 problem

1. Fusing lamp is not connected :(" title="Angry"> (reconnect it)
2. bent or is bad [img src="http://copierliquidationcenter.com/Copier_University/Smileys/default/angry.gif" alt=">:(" title="Angry"> (replace it)
3. Thermistor position incorrect [img src="http://copierliquidationcenter.com/Copier_University/Smileys/default/angry.gif" alt=">:(" title="Angry">

Try to reset this code with "Clear Mode"+107+"Clear/Stop" hold for 5s.
Turn ON and OFF the Main Switch.

.... if this is not working, you might need new Fuser Thermistor ... go to Copier Parts Outlet.com find your copier, order your copier thermistor .... they have YouTube videos how to replace them too ...

Try this Video first:
youtube.com/watch?v=2S_jH3MOwr4

SC 552 - Pressure roller warm-up error

Definition: After the main switch is turned
on or the door is closed, the
pressure roller temperature
does not reach the ready
temperature within 150
seconds during fusing unit
warm-up.

Possible Cause:
• Pressure roller fusing lamp broken
• Defective pressure roller thermistor
• Defective BCU

Troubleshooting Procedure:
1. Check if the pressure roller thermistor
is firmly connected.
2. Replace the fusing unit.
3. Replace the BCU.

After turn the main switch off and on the error appears again????
This error means that there is a bad comunication between the controller board and the operation panel.
Did you intervew in the machine? Some tecnical intervewing?

Press 'Function Clear', 1, 0, 7, then press and hold 'Clear/Stop' button for 3 secands. Machine displays SP Mode. Now turn MAIN power switch off for 5 seconds. Turn MAIN power switch back on. This should reset SC 547 code. (Main power switch is located on the left side of the copier)

press clear (yellow) and press 1,0,7 and press and HOLD the stop button 5 secs. (red) press 1 when u see the copy sp mode and press 7 (datalog) and press ok, look for the sc/ jam counter reset. press the execute 2x. turn of the machine in the main switch (orange switch on the lower front side) the shortcut mode is by pressing 7807 na press execute

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).

Enter SP mode by pressing;

• Clear (yellow) button
• 1 0 7
• Press and hold the Stop (orange) button for 3 seconds.
• Switch off and on the machine.

If SC 552 (Fusing warm up error) appears again, possible causes are;

1. Fusing thermistor defective or out of position or dirty with toner
2. Fusing lamp open, and
3. Power supply board defective.

Good luck and please rate me, thanks.

I do not recognize either of these codes (187 or 387) as part of the Aficio 2015 error list.

If the code is displayed on the screen, physically TURN OFF the copier with the main switch (red switch), wait 10 seconds and turn it back on. If it's an erroneous error, this should reset the error code. NOTE: THE ERROR CODE MUST BE DISPLAYED FOR THIS TO WORK.