MPC3001 transfer belt dirty

[chin1202]

mpc3001 after copy color,transfer belt very dirty (yellow toner )
but copy black&white ,transfer belt no dirty

what problem?
Pls help
Screenshot_20191016_214930_com.android.gallery3d.jpg

[COPIERMAN]

sounds like yellow drum unit needs to be replace . have you pull yellow unit out to see if drum unit is clean and look at how many copies on unit. good only for 120,000 copies

[FrohnB]

Replace yellow dev. unit (most common cause), and PCU (if it's towards end of life). If that doesn't take care of it, then you may have a broken wire in the ITB unit (seen it a few times).

[chin1202]

Replace yellow dev. unit (most common cause), and PCU (if it's towards end of life). If that doesn't take care of it, then you may have a broken wire in the ITB unit (seen it a few times).

dev unit what part spoilt?developer or magnetic roller?

[chin1202]

sounds like yellow drum unit needs to be replace . have you pull yellow unit out to see if drum unit is clean and look at how many copies on unit. good only for 120,000 copies

drum unit is clean.

[slimslob]

I have seen this with a dirty charge roller. Doesn't show on B/W since the color transfer rollers in the ITB assembly are not engaged.

[GIUBOSS]

if the transfer belt is so dirty, first replace the ITB cleaning unit, the accumulation of so much toner is also the result of incorrect cleaning. If the developer is old, dust everywhere, change it.