BenQ Projector M842UST User Manual

Maintenance 51
Replacing the lamp
•  To reduce the risk of electrical shock, always turn the projector off and disconnect the power cord before 
changing the lamp.
•  To reduce the risk of severe burns, allow the projector to cool for at least 45 minutes before replacing the 
lamp.
•  To reduce the risk of injuries to fingers and damage to internal components, use caution when removing 
lamp glass that has shattered into sharp pieces.
•  To reduce the risk of injuries to fingers and/or compromising image...

Maintenance 524. Disconnect the lamp connector from the 
projector as illustrated.
5. Loosen the screw that secures the lamp.
6. Lift the handle so that it stands up.
7. Use the handle to slowly pull the lamp out of the 
projector.
•  Pulling it too quickly may cause the lamp to break and scatter 
broken glass in the projector.
•  Do not place the lamp in locations where water might splash on 
it, children can reach it, or near flammable materials.
•  Do not insert your hands into the projector after the...

Maintenance 53 14. Connect the power and restart the projector.
Do not turn the power on with the lamp cover removed. 
Resetting the lamp timer
15. After the startup logo, open the On-Screen Display (OSD) menu. Go to the 
SYSTEM SETUP: Advanced > Lamp Settings menu. Press MODE/ENTER. 
The Lamp Settings page displays. Highlight Reset Lamp Timer. A warning 
message is displayed asking if you want to reset the lamp timer. Highlight Reset and 
press MODE/ENTER. The lamp time will be reset to “0”.
Do not...

Maintenance 54
Indicators
LightStatus & Description
Powe r  ev e n t s
Orange Off OffStand-by mode.
Green
FlashingOff OffPowering up.
Green Off OffNormal operation.
Orange
FlashingOff OffNormal power-down cooling
Red Off OffDownload
Green Off RedCW start fail
Red Flashing Off OffScaler shutdown fail (data abort)
Off Red OffLAN download fail
Off Green OffLAN download processing
Green Off OffBurn-in ON
Green Green GreenBurn-in OFF
Lamp events
Off Off RedLamp1 error in normal operation
Off OffOrange...

Troubleshooting 55
Troubleshooting
The projector does not turn on.
No picture
Blurred image
Remote control does not work
The password is incorrect
CauseRemedy
There is no power from the power cord.Plug the power cord into the AC power jack on 
the projector, and plug the power cord into the 
power outlet. If the power outlet has a switch, 
make sure that it is switched on.
Attempting to turn the projector on again 
during the cooling process.Wait until the cooling down process has 
completed....

Specifications 56
Specifications
Projector specifications
All specifications are subject to change without notice.
Optical
Resolution
1024 x 768 XGA (MX842UST)
1280 x 800 WXGA (MW843UST)
Display system
1-CHIP DMD
Lens F/Number
F = 2.53, f = 5.38 mm
Lamp
240 W lamp
Electrical
Power supplyAC100–240V, 4.1 A, 50–60 Hz 
(Automatic)
Power consumption
360 W (Max); < 0.5 W (Standby);
< 6 W (when the Network function in the 
Standby Settings is on)
Mechanical
Weight
6.2 kg + 0.3 kg (13.7 lbs + 0.7 lbs) with...

Specifications 57
Dimensions
322.8
236.9
Unit: mm 339 

Specifications 58
Timing chart
Supported timing for PC input
•  *Supported timing for 3D signal in Frame Sequential, Top Bottom and Side by Side formats.
**Supported timing for 3D signal in Frame Sequential format.
***Supported timing for 3D signal in Top Bottom and Side by Side formats.
•  The timings showing above may not be supported due to EDID file and VGA graphic card limitations. It is 
possible that some timings cannot be chosen.
ResolutionModeVe r t i c a l  
Frequency 
(Hz)Horizontal 
Frequency...

Specifications 59
Supported timing for HDMI (HDCP) input
•  *Supported timing for 3D signal in Frame Sequential, Top Bottom and Side by Side formats.
**Supported timing for 3D signal in Frame Sequential format.
***Supported timing for 3D signal in Top Bottom and Side by Side formats.
•  The timings showing above may not be supported due to EDID file and VGA graphic card limitations. It is 
possible that some timings cannot be chosen.
ResolutionModeVe r t i c a l  
Frequency 
(Hz)Horizontal 
Frequency...

Specifications 60
*Supported timing for 3D signal in Frame Sequential format.
**Supported timing for 3D signal in Top Bottom, Frame Packing and Side by Side formats.
***Supported timing for 3D signal in Frame Sequential, Top Bottom, Frame Packing and Side by Side 
formats.
****Supported timing for 3D signal in Side by Side format.
*****Supported timing for 3D signal in Top Bottom and Side by Side formats.
Supported timing for Component-YPbPr input
• *Supported timing for 3D signal in Frame Sequential...