C550 error C2553

[bludlow]

C-2553 M IU TCR value drops below 3.9% should be around 7% +- 1%
Actions taken:
New toner bottel
New toner hopper Assy all 4 comes at one unit
New IU
New PCRB
New MFP

Can add toner in TCR supply and yes the tcr value does increase in level history.

make 20 copies full color and C2553 errors agin.

What would alow the TCR value to drop.

[JSC]

Found this in the C451-550-650 trouble shooting guide. I can email you the booklet if you want.
If that does not work check ICP6 on the PRCB.

Good luck.

[bludlow]

The TCR sensors is on the IU and that has been replaced.
Also the TCR sensor for the toner bott is in the toner supply hopper and all 4 have been replaced....
Also i can get the TCR sensor to move up and down using halftone prints and TCR supply add,, so we know that their is toner and it is getting into the IU, But the C550 will know that the TCR sensor is bellow what it should be and it is taking no action to add toner on its own.
The board that tells the motor control board to turn on the toner supply is the PCRB. both the PCRB and the MCRB have been replaced..
the Dmax on the prints follow in relation to the TCR value.
so what reading does the mechine do inorder to say hey add toner, is it not done on the boards that have been replaced,, also the TCR sensor is working correctly becasue it does increase when toner is added and decrease when heavy converage prints are made. also the mechine knows if the TCR falls out of range becasue it throws an error code, all available firmware does the same thing, extra cards have been removed,
KMBS says its the navram??????? it will be replaced in the next 30 mins.

Any one have anytihng to add

[JSC]

sounds a real pig of a fault, you have changed everything but the Nvram so you don't have anything to lose............are you going to try an NVram recovery or just change it?

[Albonline]

see if there is any ironin the toner waste bottle. stick a magnet in it. if so check your high voltage xformer for developer bias.

[bludlow]

rebuild of toner bottle motor assy. corrected the problem. im thinking a bad seated connector..

[Sweetmusclecar]

Had the same problem,and the toner supply motor did it for me,thanks for all the input.