Changhong 21BM91 chassis CN-18EAV2 service mode
To enter the DESIGN/SERVICE mode Set the volume to no sound. Then press and hold the MUTE button on the remote control, and press the MENU button on the TV to enter the factory mode. In this case, red “S”is displayed on the upper center of the screen. To exit from the S mode, turn off the Changhong TV set by the POWER button on the remote control. Caution: The user service mode adjustment can be changed only when service personnel adjust the whole set data during servicing. As the control data have dramatic effects on functions and performance of the TV, service personnel should not tell user how to enter the SERVICE mode to avoid improper data settings.
Changhong 21BM91 TV Service Menu
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