MPC3500 SC 551

[bostjanma]

Hi,
I have many time SC 551 depend, my be once per month. I changed both termistors and upgrade Firmware and checked conectors. After this interventions the copier sometimes still show this code. After reset work normaly.
Any idea from your side?

Thanks

[Jomama46]

551 really means its not coming to temp fast enough. Is the machine sitting in a cold room, is it under an air conditioning duct? Is it connected to a good source of AC power?

[TonerMunkeh]

Could be the IH coil or the drive board is on it's way out, a dodgy coil would stop the belt coming up to temperature quickly enough. The IH coils have always been a pain on this model, and worse still - they're a bastard to change.

[Fearless V K]

[Symptom]
SC551 (thermistor disconnect: thermistor2) or SC561 (thermistor disconnect: thermistor3) is displayed.

[Cause]
The drawer connector surface is partially corroded.
A foreign object or debris has adhered to the surface of the fusing unit drawer connector contact and, when the adhered moisture melts due to condensation, it causes part of the surface of the drawer connector to corrode. It becomes clear that SC551/SC561 occur because of faulty contact with the image fusing unit.

[Resolution]
Replace the drawer connector on the device.