Customer has an Sc-405 code. They reset it by turning off machine then on. The machine only works for part of day then go's back into sc-405 code again.

This is related to SP311 models.

Execute "Fuser SC Reset" to recover the machine after completing the
recovery procedure. Otherwise, the machine continues to issue this SC
code and cannot be operated.

Fusing related SCs
To prevent damage to the machine, the main machine cannot be operated until the fusing related
SC has been reset by a service representative.
? Enter the "Engine Maintenance" in the "Maintenance mode".
Press "Execute" in "Fuser SC Reset" with engine maintenance mode, and then turn the main
power switch off and on.

sc302 is usually PCU or charge roller.
As you say you have recently replaced the Drum/PCU, is the drum turning correctly?

Check charge connectors and connectors on the back of the pcu. To reset that code, simply turn main power off and on again. If problem comes right back....the machine detects the cause still exists. May be an issue with the HVT.

In general the SC 860-900 refer to HD acces error.
SC 865 - the hard disk detected an error.Error detected other that the bad sectors error SC 863 or the CRC error SC 864.Reset the error code by turn the operation switch and main power switch OFF and ON.Try disconnect and reconnect the hard disc connectors and verify the cable.

Sc 546 means Unstable fusing temperature Possible Cause : 1-Thermistor disconnected or defective 2-Fusing unit drawer installed Incorrectly To reset that code do this: Press the Clear Mode key. Use the keypad to enter "107". Hold down Clear/Stop for at least 3 seconds. Enter the Service Mode. Do sp 5810 (SC Code Reset )

The Ricoh Aficio MP 161 LN give error code - SC 302

Please adivse

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).

The SC - 928 is a Memory error problem.
The machine detects a discrepancy in
the write/read data during its write/read
test (done at power off/on and at
recovery from low power or night/off
mode). To try to reset this code -- Turn the MAIN power switch off, wait about 30 secs. then turn switch back On.

Possible causes:
• Memory defective
• BICU defective
• Poor connection between BICU and
memory
The cheapest repair would be to replace the memory. It is rare the the connections came apart unless some one was in the back of the machine for some reason.

Hello sir; try to turn off and back on the machine to reset, if don't work next few steps need to follow;
1, press "clear mode" then enter 107 then press and hold "clear/stop" key until SP mode show up.
2, turn power off and back on .

The error is about the fusing unit for to reset the code you must enter into the service menu and reset the SC code 517
For to enter the service menu you should do the follow steps :
1.Enter the service menu by pressing the follow keys in order: yellow key[clear modes] then press "107" number one after other and then press and hold the red key [clear/stop]
2.Hold it down until service mode do not appear if not appear after 10 seconds try again.
After you will be in service mode press the follow numbers :5810 and then will apear on the screen "SC reset" set the value from "0" to "1".
Then turn off and after 5 seconds turn it on the machine.
Please replay if this do not help and write the SC code good because i cannot find the code SC517

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.