Specifications

3. ELECTRICAL COMPONENT DEFECTS
3.1 SENSOR
Component Condition Symptom
Scanner Home
Position Sensor
(S1)
OPEN
(CN122-4 stays HIGH)
SC code (E22) is displayed.
SHORTED
(CN122-4 stays LOW)
SC code (E21) is displayed.
Lens Home
Position Sensor
(S2)
OPEN
(CN102-8 stays HIGH)
SC code (E29) is displayed.
SHORTED
(CN102-8 stays LOW)
SC code (E28) is displayed.
4th/5th Mirror Home
Position Sensor
(S3)
OPEN
(CN102-11 stays HIGH)
SC code (E2A) is displayed.
SHORTED
(CN102-11 stays LOW)
SC code (E2B) is displayed.
Registration Sensor
(S4)
OPEN
(CN101-9 stays HIGH)
"Check Paper Path" indicator
(location "A" or "B") blinks when a
copy is made.
SHORTED
(CN101-9 stays LOW)
"Check Paper Path" indicator
(location "A" or "B") lights when the
main switch is turned on.
Exit Sensor
(S5)
OPEN
(CN141-2 stays HIGH)
"Check Paper Path" indicator
(location "D") blinks when a copy is
made.
SHORTED
(CN141-2 stays LOW)
"Check Paper Path" indicator
(location "D") lights when the main
switch is turned on.
Paper End Sensor
1st and 2nd
(S6 and S7)
OPEN
(1st: CN125-5 stays HIGH)
(2nd: CN139-4 stays
HIGH)
"Load Paper" indicator lights even
when paper is in the cassette or tray.
SHORTED
(1st: CN125-5 stays LOW)
(2nd: CN139-4 stays LOW)
"Load Paper" indicator lights even
when the cassette or tray is empty.
Toner End Sensor
(S8)
OPEN
(CN114-2 stays HIGH)
The CPU detects toner end condition
using Vsp/Vsg value.
If the ID sensor is defective, the CPU
fails to detect toner end and the
image density may become too low.
SHORTED
(CN114-2 stays LOW)
Toner Overflow
Sensor
(S9)
OPEN
(CN101-2 stays HIGH)
"E70" blinks in the magnification
indicator even when used toner tank
is not full.
SHORTED
(CN101-2 stays LOW)
"E70" does not blink.
1 December 1990
6-53