Canon iPF780 Series Service Manual page 232

[Check 2]
Check whether the multi sensor performance has degraded or whether the media is compatible.
When "Density gain" and "Density current value" are maximum values and "Density media output" is 168 or less, an error occurs.
Maximum value of "Density gain": 255
Maximum value of "Density current value": 245
When the multi sensor performance and media are normal, "Density gain" is about 5-100; "Density current value" is about 200.
10) NOZZLE CHECK
Checks for non-discharging nozzle with head management sensor.
11) NOZZLE INF
Displays the result of non-discharging nozzle check performed with "NOZZLE CHECK" by nozzle row of each ink color.
- Press the key or key to switch the ink color.
- AE:A-EVEN row, AO:A-ODD row, BE:B-EVEN row, BO:B-ODD row
12) MEMORY CHK
13) HEAD CNT CHK
Confirms the contact status of the printhead.
14) CR ERR CHK
This mode performs the self diagnosis about the drive state of the carriage unit.
Perform in case the drive state of the carriage unit is abnormal. it can guess the failure cause of the carriage unit as shown in the followings.
- Carriage motor failure
- Linear encoder sensor failure
- Linear scale failure or overload state
* When performing this mode, open and close the upper cover by following the instructions on the screen.
After displaying the following screen, press the [OK] key to start the self diagnosis, and then the diagnosis result is displayed.
If the failure is found, check and replace the corresponding parts or surrounding parts.
- Normal
- Carriage motor failure
- Linear encoder sensor failure
- Linear scale failure or overload state
C A E : O K
B E : O K
Display
DDR Checks the DDR-SDRAM mounted on the Main Controller PCB.
EEP Checks the EEPROM.
C R H P S N
P R E S S
C R C H E C K
C H E C K
C R M O T O R
C H E C K
C R E N C
C H E C K
E N C o r
C H E C K
A O : O K
B O : O K
F-7-17
Description
S O K
O K K E Y
F-7-18
O K
E N D
F-7-19
E R R
E N D
F-7-20
S E N S E R R
E N D
F-7-21
O V E R L O A D
E N D
F-7-22
Chapter 7
7-19