Brother MFC-9840CDW Service Manual

Confidential
1-68
8. TROUBLESHOOTING OF THE CONTROL PANEL
Nothing is displayed on the LCD.
User Check
- Verify if the power switch is turned off.
- Pull out the power supply cord from the power outlet and leave it for 5 minutes or more.
Then, insert it to the power outlet again and turn on the power supply.
Step Possible cause Check Result Remedy
1
Connection
between main
PCB and control
panel PCB
Are the main PCB and
control panel PCB
connected properly?
No
Reconnect the connector
properly.
2
Harness between
main PCB and
control panel PCB
Is the harness damaged? Yes
Replace the harness with
a normal one.
3
Connection
between main
PCB and PS PCB
unit
Are the main PCB and PS
PCB unit connected
properly?
No
Reconnect the connector
properly.
4
Harness between
main PCB and PS
PCB unit
Is the harness damaged? Yes
Replace the harness with
a normal one.
5
LCD Is the problem solved
after replacing the LCD?
Yes
Replace the LCD.
6
Control panel
PCB
Is the problem solved
after replacing the control
panel PCB?
Yes
Replace the control panel
PCB.
7
PS PCB unit Is the problem solved
after replacing the PS
PCB unit?
Yes
Replace the PS PCB unit.
8 Main PCB Is the problem solved
after replacing the main
PCB ASSY?
Yes
Replace the main PCB
ASSY.

Brother MFC-9840CDW Specifications

General

Print technology	Laser
Maximum resolution	600 x 2400 DPI
Economical printing	Yes
Time to first page (black, normal)	16 s
Time to first page (color, normal)	17 s
Print speed (black, normal quality, A4/US Letter)	20 ppm
Scan to	E-mail, FTP, OCR, USB
Scanner type	Flatbed scanner
Grayscale levels	256
Input color depth	48 bit
Maximum scan resolution	19200 x 19200 DPI
Optical scanning resolution	1200 x 2400 DPI
Copier resize	25 - 400 %
Maximum copy resolution	1200 x 600 DPI
N-in-1 copy function (N=)	4, 9, 16, 25
Copy speed (black, normal quality, A4)	16 cpm
Faxing	Mono faxing
Fax memory	400 pages
Modem speed	33.6 Kbit/s
Fax speed dialing (max numbers)	300
Total input capacity	250 sheets
Total output capacity	150 sheets
Multi-Purpose tray input capacity	50 sheets
Auto document feeder (ADF) input capacity	35 sheets
Internal memory	128 MB
Sound power level (standby)	30 dB
Sound pressure level (printing)	54.5 dB
Custom media sizes	(69.9 - 216mm) - (116 - 406.4mm)
Dimensions (WxDxH)	530 x 539 x 520 mm
Networking features	10/100Base-TX
Wireless technology	IEEE 802.11b/g
All-in-one functions	Copy, Fax, Scan
Maximum internal memory	0.640 GB
Color all-in-one functions	copy, print, scan
Media weight (tray 1)	60 - 105g/m2
Paper tray media types	Bond paper, Envelopes, Labels, Plain paper, Recycled paper
Non-ISO print media sizes	Executive (184 x 267mm), Folio (media size), Legal (media size), Letter (media size)
ISO A-series sizes (A0...A9)	A4, A5, A6
ISO B-series sizes (B0...B9)	B5, B6
JIS B-series sizes (B0...B9)	B5
Maximum ISO A-series paper size	A4
Multi-Purpose Tray media weight	60 - 163 g/m²
Security algorithms	LEAP
Supported network protocols (IPv4)	TCP/IP (IPv4 & IPv6)
Standard interfaces	USB 2.0
USB 2.0 ports quantity	1
Bundled software	ScanSoft PaperPort (Win) NewSoft Presto! PageManager (Mac)
Power consumption (PowerSave)	36 W
Power consumption (average operating)	515, 100 W
Package weight	45800 g
Digital sender	No
Maximum duty cycle	3000 pages per month
Market positioning	Business