Lexmarl C748DE No Red at all

[Phil B.]

do you have a menu option i service mode to be able to SWAP toners? ( like HP DISABLE cart check? )

have you checked laser shutter?

my guess compat toners... bad transfer ( if ROS is not the issue )

[Lance15]

The laser in this model is a block like the 3600/3800/CP3505 machines. They don't have the shutters to keep the glass clean. Never thought about aftermarket toner considering all explanations only seem to point to magenta. My guess would be the charge roller underneath the belt associated with magenta. Have never seen where you can only order a charge roller. Gotta replace the whole belt.

[Dave]

I did a stop test and I have no magenta on the drum. I found out today that the magenta cartridge is definitely new and genuine Lexmark brand. I also swapped the drum again and cleaned the ground contacts for it. Also found the test for the toner sensor and that is changing state as it should. I’m still researching the manual because it feels like there is something particular to lexmark or this model that I am not aware of... I’m not sure changing the transfer belt will help, there didn’t appear to be anything there to transfer. It could a bad laser but there no errors logged. More later

The laser in this model is a block like the 3600/3800/CP3505 machines. They don't have the shutters to keep the glass clean. Never thought about aftermarket toner considering all explanations only seem to point to magenta. My guess would be the charge roller underneath the belt associated with magenta. Have never seen where you can only order a charge roller. Gotta replace the whole belt.

[Dave]

Thanks and I appreciate all the valuable and thought provoking input. I do not have a spare transfer belt unit and I don't want to pop for a new one so I am going to take the belt and rollers off the unit, clean it, and when I put it back together I will swap the magenta transfer roller with cyan or yellow. I'll keep you posted.
Lance15, do you know if I should see an error code on this particular model if the laser does not turn on? Is there a beam detect sensor on this model?

[Dave]

I jus found this in the manual. It looks like it enables cartridge swap.Enforce color order LEXMK.jpg

do you have a menu option i service mode to be able to SWAP toners? ( like HP DISABLE cart check? )

have you checked laser shutter?

my guess compat toners... bad transfer ( if ROS is not the issue )

[Phil B.]

I jus found this in the manual. It looks like it enables cartridge swap.Enforce color order LEXMK.jpg

there ya go.. enable .. switch carts... see if problem travels to the new spot

[Dave]

The problem did not move with the cartridge. Correct me if I am wrong, transfer issue or Laser issue.
Thanks!!

there ya go.. enable .. switch carts... see if problem travels to the new spot

[Phil B.]

The problem did not move with the cartridge. Correct me if I am wrong, transfer issue or Laser issue.
Thanks!!

Well..ROS replacement can b PIA.. can you rob an ITB to test?

Sent from my SM-G960U using Tapatalk

[Lance15]

Correct me if I'm wrong, but, I think typically with these block type laser/scanners, there are two physical lasers that do two colors each. Say, BLACK & CYAN and MAGENTA & YELLOW. If you've got yellow, you'll have magenta too.

[Phil B.]

Correct me if I'm wrong, but, I think typically with these block type laser/scanners, there are two physical lasers that do two colors each. Say, BLACK & CYAN and MAGENTA & YELLOW. If you've got yellow, you'll have magenta too.

well hell... yes they would split two colors... digress

so Lance you have narrowed it down to ITB!