Service manual
TONER SUPPLY UNIT
2-H-3
2 UNIT EXPLANATION
2. Signals
a. Input signal
(1) TLD (TLD to PRCB)
When the level of toner in the cartridge becomes
low, this signal goes low [L], displaying a mes-
sage on the LCD connected to the OB1.
(2) M15 EM (M15 to PRCB)
M15 fault detection signal.
[L]: M15 normal
[H]:M15 Abnormal
b. Output signals
(1) TLD CONT, TSEN_CONT (PRCB to TLD)
TLD power control signal.
The TLD is powered only when it is detecting the
toner level.
(2) M15 CONT (PRCB to M15)
M15 control signal.
[L]: M15 ON
[H]: M15 OFF
(3) M15 CLK (PRCB to M15)
Clock signal for M15.
[4] M11 (Toner Supply 1) Control
M11 (Toner Supply 1) is controlled directly by PRCB
(printer control board). The toner density is detected by
TCSB (toner control sensor board).
1. Operation
a. Detection of toner density
The Dmax sensor (PD1) mounted on the TCSB
detects the density of the toner control chart
developed on the drum surface to output the sig-
nal corresponding to the detected density to the
PRCB.
b. Toner supply
When the voltage detected by the TCSB is below
the specified value, the PRCB issues a control
signal to drive the M11. The relationship
between the paper size and toner supply time is
summarized in the following table:
Paper size Supply time (sec.)
A3
1.14
B4
0.86
F4
0.86
A4
0.57
A4R
0.57
B5
0.43
B5R
0.43
A5
0.29
A6
0.22
DCPS2
PRCB
M11
24VDC
PGND
24VDC
24VDC
M11 DRIVE A
M11 DRIVE A
M11 DRIVE B
M11 DRIVE B
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