A line down the length of the sheet, a spot that repeats, a faded colour, or toner that rubs off by hand. Each of these defects has a different source inside the machine, and replacing the wrong part means money spent and the defect still there.
This guide helps you work out where the defect is coming from before you order a part or call the technician. It is written for Ricoh Pro machines (C5100, C5200, C7100, C7200X, C9100, C9200, 8100).
First of all: three questions that do half the diagnosis
- Is the defect in one colour, or in all colours? Print a page for each colour on its own (black, cyan, magenta, yellow). If the defect is in one colour only, the problem is in that colour’s unit: its drum, developer or cleaning unit. If it is in all colours, the problem is in something shared: the transfer belt (ITB) or the fuser.
- Which direction does the defect run? A line down the length of the sheet (in the direction the paper travels) is different from a line across it.
- Does the defect repeat at a fixed distance? If a spot or dot appears every so many centimetres, there is a roller or drum with a defect at one point, printing it on every turn. Measure the distance between two repeats and tell the engineer, because each roller has a different circumference and the distance points to it.
Quick table: the defect and its most likely source
| What you see on the paper | Most likely source |
|---|---|
| Lengthwise lines down the sheet in one colour | The drum or the drum charge unit |
| Dots or defects repeating at fixed distances | The drum |
| A light grey background on white paper | The drum and its charging, or the developer |
| Lines or bands repeating in the same place, and toner spots | The drum cleaning unit (blade, lubricant bar, brush) |
| Toner on the back of the sheet or on its edges | The drum cleaning unit |
| Colours faded, or not steady from one sheet to the next | The developer |
| Toner dust on the paper | The developer |
| Colours out of register, a shadow or coloured edges | The transfer belt (ITB) and its components |
| Spots or lines across the sheet | The transfer belt (ITB) and its components |
| Toner rubs off when you rub the sheet with your finger | The fuser |
| Creasing or curling of the paper after printing | The fuser |
| One colour paler than the rest, with light streaks in it | The toner is about to run out |
The drum and the charge unit
The drum is where the image forms before it is transferred to the paper. When its surface wears or is scratched you get:
- Lengthwise lines down the sheet.
- Fading or uneven printing in one colour.
- Dots or defects repeating at fixed distances.
- A light grey background on white paper.
The same symptoms can come from the drum charge roller or the corona wire, which have a shorter life than the drum itself. So not every lengthwise line means a new drum. Drum and charge parts for each model are in the drum section of the parts catalogue.
The drum cleaning unit: blade, lubricant bar and brush
The cleaning unit cleans the drum after every turn. If the blade, the lubricant bar or the brush is worn out, excess toner stays on the drum and prints again:
- Lines or bands repeating in the same place.
- Toner spots on the paper.
- Toner on the back of the sheet or on its edges.
These parts have a shorter life than the drum and are changed more often, and sometimes come together in one maintenance kit. See the cleaning unit section.
The developer
The developer carries toner to the drum. When it reaches the end of its life:
- Colours fade, or do not hold steady from one sheet to the next.
- A grey background or toner dust appears on the paper.
- The machine shows a message that the developer has reached the end of its life.
If the fading is in one colour and the toner is full, that colour’s developer is the first thing to check. All colours are in the developer section.
The transfer belt (ITB) and its components
The belt collects the four colours on top of each other and transfers them to the paper, so any problem in it shows in all colours together:
- Colours out of register, with a shadow or coloured edges around the letters.
- Spots or lines across the sheet.
- Faded areas or uneven gloss.
This group has many parts: the belt itself, the charge rollers, the belt’s own cleaning unit, and the transfer and separation unit. The engineer is the one to say which. The parts are in the transfer belt section.
The fuser
The fuser fixes the toner to the paper with heat and pressure. Its symptoms are clear:
- Toner rubs off when you rub the sheet with your finger.
- Creasing or curling of the paper after printing.
- Uneven gloss, or repeating spots.
- Fuser errors on the machine’s screen.
If toner rubs off on heavy paper only, first check that the paper type and weight are set correctly in the tray settings, because the machine sets the fuser temperature from them. Fuser parts are in the fuser section.
Not every defect means a new part
Sometimes cleaning or a colour calibration solves the problem without changing anything. And sometimes the defect comes from the paper itself: damp or badly stored paper gives results that look like fuser and transfer defects.
So before you order a part:
- Print a page for each colour on its own.
- Photograph the defect clearly, and photograph the whole sheet so the direction and the repeat can be seen.
- Send the photos and the machine model on WhatsApp.
Our engineers look at the photos first and tell you whether the problem can be solved by cleaning or calibration, or needs a part, and exactly which part.
