Error message U2, does not start - Xerox WorkCentre Pro 320/315 XL

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Thread Sharp AR M236 Service code U2 40

U2 04 EEPROM serial communication error
Change cartridge

in order press

* Entering the simulation mode

1) #/P key (program) ON → Asterisk (*) key ON → CLEAR key ON →
Asterisk (*) key ON → Ready for input of a main code of simulation
Simply # * C * and the machine will enter simulation mode.

Then enter the number 16, which is U2 code correction, follow what the screen says, Normally just press start and the machine will reset.
U2 codes are software glitches. A U2 40 is a CRUM fault which is a drum or toner chip problem.
Sim 16 almost always clears them.

u2-40 CRUM chip communication error

Press #, Interrupt, C, Interrupt. Enter 16 print.

Hello sir; This error code it can be reset folloe the instruction;
1, press "clear", "interupt", " 0 ", "interupt"
2, enter 16 then press start.

Push P * C* in quick succession to enter simulation mode. Once there, enter 16 on the keypad. push the print button (like making a copy). Push 1 for yes then print button again. push the CA button. Copier should reboot and run fine for you.

U2 RAM error
U2-00 EPROM error
U2-01 Counter error
U2-01 Memory back-up battery dead
U2-04 EPROM error
U2-11 Main counter error
U2-12 EPROM error

As you can see there are many U2 error codes. Needless to say, find your code and the replace the bad part. The battery is on the main board. The EPROM is on the main board.
If you find your code, replace the part and error still remains -- replace main board.

To find out the sub code for the U2 error hold down the Start key. Below is a list of the errors:
U2-04 EEPROM serial communication error
U2-11 Counter check sum error
U2-12 Adjustment value check sum error (EEPROM)
U2-40 CRUM communication error

To clear the U2-40 error try pulling out the toner cartridge and firmly reinstalling it. If that doesn't work you must install a new toner cartridge. There is a CRUM chip on the cartridge that keeps up with how many impressions have been made with that cardridge. You cannot "refill" these cartridges without replacing the CRUM. This problem occurs frequently with remanufactured cartridges.

To clear other U2 errors you must enter simulation mode.
Perform the following procedure to enter the simulation mode.
Clear key - Interrupt key - "0" key - Interrupt key - 16 - Start key - Start key. The unit should reset.