I have an error code 0094, and have the service manual went through the check, all working fine apart from changing the printer circuit board, what else could be , any suggestion ? thank you

It mean "Vh voltage error" and can be cause of short circuit in the printhead . Sometimes you can get good result with printhead changing, but it is not guarantied because of possible printer electric parts (carriage board, flat cable, motherboard or power supply) damage. For printhead changing, delete paper and use Service mode (hold Paper sourse + Information while switching printer on).

According to the service manual an error has occured writing to the eeprom on the logic circuit board. I would look at the logic board as a culprit . You may need to check the voltage is correct at the power point and matches the printer required supply voltage. What worries me is what caused the logic board to fail and make a burning smell. Could be a faulty voltage regulator supplying the logic board or a fault in a power board..
http://internaute.free.fr/depannage_canon/mp610/mp610-sm.manuel.reparateur.pdf

Here are the steps they recommend in the users manual for a c55 error.



5.1.11 Optional communication related service call
[C55] ADF I/F error
[F11] ADF I/F error
(1) Check if the connector CN71 on the ADF/RADF board is disconnected.
(2) Check if the relay connector between the ADF/RADF board and the PFC board is disconnected.
(3) Check if the connector CN246 on the PFC board is disconnected.
(4) Check if the connector pins are disconnected and the harnesses are open circuited.
(5) Check if the conductor patterns on the ADF/RADF board and the MAIN board are short circuited
or open circuited.
(6) Replace the ADF/RADF board.
(7) Replace the MAIN board

Its either the fuser flag or pressure switch would be my guess. Remember when troubleshooting something. KISs....Keep It Simple....its usually the easiest thing that fixed the problem. Replace the fuser then work out from there, especially since you have a spare machine to work from. Here is the Canon Service manual page on it. Good Luck!!
From the Canon Service Manual:
50.7 Fuser Error : Fuser has experience a pressure-release mechanism error

1) Reseat the following connectors: fuser motor, fuse-unit home-position, intermediate & the DC controller PCB
2) Test the Fuser Pressure-release sensor by performing the paper-path test or the manual sensor test

3) Check the sensor flag on the Fuser Pressure-release sensor. If the sensor flag is damaged, replace the fuser.
4) Check the inside gear on the product that drives the fuser
5) Perform the fuser motor & fuser pressure release motore components test.
6) Replace the fuser Motor
7) Replace the Fuser

The Service Manual for the MP500, which is very close to the MP450, indicates that the error code of 6500 is a PCI buss error and this is a Service Error Code. Typically this is an internal error of one of the ASCI chips on the logic board and can only be repaired by replacing the logic board at the Canon Service Center.

If you want to take the time to try and repair it, you can take the unit apart and search for a loose connection, or unplug and replug all connections. Other than that, you can sell it for parts.

Good luck

I HAVE A PRINTER SAMSUNG ML 2550 ERROR CODE MDLCRUM 0094

For error code C44, it indicates Heater abnormality.

If 1st time occur, u can just go to 08-400, reset the value to "0" then restart the machine.

If happen again, then u need to check the thermistor. Replace it if necessary. If themistor replaced but still happen again, then u need to proceed to check themostat--> heater-->Mainboard-->Switching regulator.

5A: encoder disc or encoder strip or main circuit board or printhead circuit board or power supply defective!

Sorry, cant be fixed by yourself!

error code E00020-0081 my canon printer IRC3170i.what is the problem?Anybody can help?

The 6500 error code is a logic board error code. The PCI Bus error is detected by the ASCI. Sounds like it needs new logic board.