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How to enter the service mode of BenQ 2450HM Monitor, how to update the firmware, power board - SMPS - schematic and general troubleshooting

BenQ G2450HM, GL2450HM, GL2450HE MONITOR how to update the firmware, SMPS schematic, troubleshooting, Service mode

How to enter the service mode

Connect signal source and power cable to monitor and DC off it.

Press “menu” key and “power on” key synchronously as below figure. When the screen lights, release the two buttons and then press “menu” again to open below factory menu.

If a bad smell or an abnormal sound appears to come from the monitor, contact your nearest BenQ service center for assistance immediately.

Be careful do not touch the rear side directly because of the backlight high voltage.

F/W Upgrade SOP: Upgrade by 715GT089-B/ C

Materials list

Connection

Install the USB driver

When insert the USB cable to PC USB port, will pop up a Hardware Wizard to help you install the USB driver if you use this ISP board first time. You can install it successfully as the below instruction step by step.

Remark: The USB driver files path: D:\FTC100103(Mstar)\FTCUSB.INF

Install the ISP tool.:  Copy the three files in one folder. And then double click ISP tool.exe

Set the parameters in “Device” window. Tick “WP Pin pull to high during ISP”.

Connect to the monitor. Click “Connect”. If the tool communicate with monitor successfully, the tool will detect the flash type of monitor.

Load the F/W you want to upgrade.

Set the restore address.:  fill “0x03F000” and “4KB” as follow.

Set parameter in “Auto” window. If you have set “Restore address”, please tick “Restore Data”.

Processing of upgrade. After clicking “Run”, the tool start to program. It is forbided to power off monitor or switch off connection during programming.

Successful upgrade. When upgrade successful, there will be green Pass letter appearing.

Check the FW version after upgrade.（ Take below figure as an instance）

(1)Connect signal source and power cable to monitor and DC off it.

(2) Press “menu” key and “power on” key synchronously as below figure. When the screen lights, release the two buttons and then press “menu” again to open below factory menu.

If the version is right, please do factory reset in user menu as below, or re-upgrade F/W as the above steps.

The reset will turn off burn in mode.

Troubleshooting.Can’t Entry ISP Mode?  Click “Config” to check the port type is USB. If no selection of USB as below please disconnect the JIG and then link it again.

Check the cables and ISP JIG are connected fluently.

Click the “Dis Con” and click “Connect” again.

AC off the monitor for a while and retry it.

Change advanced ISP tool.

Change ISP JIG or cable.

Change PC.

Power Board Schematics: GL2450HM//GL2450HE 715G5000P01000003H and G2450HM 715G5000P01001003H

GL2450HM//GL2450HE 715G5000P01000003H SMPS schematic

G2450HM 715G5000P01001003H: SMPS schematic

Troubleshooting

The image is blurredR

Readthe instructions on the link "Adjusting the Screen Resolution" on the CD, and then select the correct resolution, refresh rate and make adjustments based on these instructions.

How do you use a VGA extension cable

Remove the extension cable for the test. Is the image now in focus? If not, optimize the image by working through the instructions in the "Adjusting the refresh rate" section on the link "Adjusting the Screen Resolution". It is normal for blurring to occur due to conduction losses in extension cables. You can minimize

these losses by using an extension cable with better conduction quality or with a built-in booster.

The blurring only occur at resolutions lower than the native (maximum) resolution.

Read the instructions on the link "Adjusting the Screen Resolution" on the CD. Select the native resolution.

Pixel errors can be seen

One of several pixels is permanently black, one or more pixels are permanently white, one or more pixels are permanently red, green, blue or another color.

Clean the LCD screen.

Cycle power on-off.

These pixels are permanently on or off and that is a natural defect occurs in LCD technology.

The image has a faulty coloration

It has a yellow, blue or pink appearance.

Select MENU > PICTURE > Color > Reset Color, and then choose “YES” in the “Caution” message box to reset the color settings to the factory defaults.

If the image is still not correct and the OSD also has faulty coloration, this means one of the three primary colors is missing in the signal input. Now check the signal cable connectors. If any pin is bent or broken off, contact your dealer to get necessary support.

No image can be seen

Is the prompt on the display illuminated in green?

If the LED is illuminated in green and there is a message “Out of Range” on the screen, this means you are using a display mode that this monitor does not support, please change the setting to one of the supported mode. Please read the “Preset display modes” section from the link "Adjusting the Screen Resolution".

Faint shadow from the static image displayed is visible on the screen

Activate the power management function to let your computer and monitor go into a low power "sleep" mode when not actively in use.

Use a screensaver to prevent the occurrence of image retention.

The prompt on the display illuminated in orange

If the LED is illuminated in orange, the power management mode is active. Press any button on the computer keyboard or move the mouse. If that does not help, check the signal cable connectors. If any pin is bent or broken off, please contact your dealer to get necessary support.

The prompt on the display not illuminated at all

Check the power supply mains socket, the external power supply and the mains switch.

The image is distorted, flashes or flickers

Read the instructions on the link "Adjusting the Screen Resolution" on the CD, and then select the correct resolution, refresh rate and make adjustments based on these instructions.

Running the monitor at its native resolution, but the image is still distorted

Images from different input sources may appear distorted or stretched on the monitor running at its native resolution. To have the optimal display performance of each type of input sources, you can use the "Display Mode" function to set a proper aspect ratio for the input sources.

The image is displaced in one direction

Read the instructions on the link "Adjusting the Screen Resolution" on the CD, and then select the correct resolution, refresh rate and make adjustments based on these instructions.

OSD controls are inaccessible

To unlock the OSD controls when the OSD is preset to be locked, press and hold the “MENU” key for 15 seconds to enter the “OSD Lock” option and make changes.

Alternatively, you may use < or >  keys to select “NO” in the “OSD Lock” submenu from the “OSD Settings” menu (under SYSTEM), and all OSD controls will be accessible.