TVs are produced by Mitsubishi Electric Corporation. The date of birth of the company Mitsubishi Electric is considered the year 1921. Then, Mitsubishi Electric Corporation demerged from Mitsubishi Shipbuilding Co. Since the 1980, there was a rapid growth of the Corporation, its cutting-edge technology bewitched. Acquiring a TV of this brand, the buyer never lost. Thus, users can take to the troubleshooting table below.
Mitsubishi DLP 740 Series television troubleshooting
| Symptom | Remarks | |
|---|---|---|
| General TV Operation | ||
| 1. | The TV remote control does not work. | • Check that the batteries are fresh and installed correctly. |
| • Check that the control mode on the remote is set to TV. | ||
| • Be no more than 20 feet from the TV when using the remote control. | ||
| • Program the remote control to operate the TV or other device. | ||
| • Reset the remote control. | ||
| 2. | When I try to use the remote control, the POWER key blinks five times. | Replace the batteries. |
| 3. | TV does not respond to the remote control or to control-panel buttons and TV will not power on or off. | • Unplug the AC power cord for 10 seconds. |
| • Press and hold the POWER button on the control panel to perform system reset. | ||
| 4. | When a device is selected from the Activity menu, the screen is blue or black (no signal source). | • Make sure the selected device is turned on. |
| • Begin play of the device. | ||
| 5. | You have forgotten your Lock menu pass code. | |
| 6. | Rating restrictions are not working. | Open the Lock > Parental Lock menu and: |
| • Verify that the ratings locks are active. | ||
| • Check the Lock Time/Unlock Time to check if rating restrictions are disabled. | ||
| • Rating restrictions apply only to content on the ANT input. | ||
| 7. | On-screen displays appear each time you change a function. | Normal TV operation. |
| 8. | I have turned on CEC for my HDMI devices but control is erratic and I wish to disable it. | • First turn off the TV’s HDMI control for the specific device. Open the Inputs > HDMI Control menu, select the device, select Off. |
| • Disable CEC on the device itself. | ||
| • If the problem persists, do the following: | ||
| 1. Disconnect the device from the TV. | ||
| 2. Open the Inputs > Name menu and select Delete for the device. | ||
| 3. Reconnect the device to the TV and Auto Input Sensing will recognize the device with CEC disabled. | ||
| TV Channels | ||
| 1. | The TV takes several seconds to respond to channel changes. | • It is normal for digital channels to take longer to tune in. |
| • Press ENTER after entering a channel number to avoid delays. | ||
| • Use a 4-digit number for an over-the-air digital channel. | ||
| • Use a 6-digit number for digital cable channels if your cable service is able to recognize 6-digit channel numbers. | ||
| 2. | You cannot access a channel. | • Use number keys instead of CHANNEL Up/Down. |
| • Be sure the channel you want to view is in memory. | ||
| • Check that the TV is switched to the correct device or antenna for that channel by pressing the ACTIVITY key. | ||
| • Make sure the Lock > Parent menu lock is set to Off. | ||
| • If you cannot tune to a virtual digital channel even though the TV has already memorized digital channels, tune to the physical channel number used by the broadcaster. The virtual channel will then be automatically added to memory. | ||
| • You may be trying to tune to an analog channel that is no longer broadcasting. | ||
| 3. | When ChannelView list is displayed, information appears incomplete | • Press INFO to update the display for the highlighted channel. |
| • Program information is displayed only for the currently tuned channel. | ||
| • Available information is sent from the broadcaster or cable provider. No other data is available. | ||
| • Make sure the TV clock is set correctly. | ||
| TV Power On/Off | ||
| 1. | TV takes an excessively long time to power on. | • When powered on, the TV needs time to boot up, just as does a computer. |
| • For faster power-up, change the Energy setting to Fast Power On (Initial > Energy menu). With this setting the TV’s power usage when off exceeds ENERGY STAR® recommended levels for a powered-down device. | ||
| 2. | You cannot program the TV to turn on automatically (Timer function) | • The TV may be locked. |
| • The clock may not be set. | ||
| 3. | TV turned itself off and the light on the front panel started to blink. | • Momentary power fluctuation caused the TV to turn off to prevent damage. Wait for the green light to stop flashing and turn the TV on again. |
| • If the TV does not stay on, press the POWER button on the control panel for at least eight seconds to perform System Reset. If this happens frequently, obtain an AC line power conditioner/surge protector. | ||
| • An unusual digital signal may have been received, triggering a protection circuit. Wait for the light to stop flashing and turn TV on. | ||
| 4. | TV will not power off. | Press the POWER button on the control panel for ten seconds to perform System Reset. |
| Picture | ||
| 1. | Picture does not look like a high-definition picture. | Not all signals are high-definition signals. To receive high-definition programming from your cable or satellite provider, you must subscribe to the provider’s high-definition service. Some overthe-air broadcasts are in high-definition and can be received with a high-quality antenna suited to your location. |
| 2. | TV has sound but no picture. | • Check that all video inputs are plugged in firmly. |
| • Press and hold the POWER button on the control panel for ten seconds to perform System Reset. | ||
| 3. | Picture has become dimmer. | Adjust picture brightness and contrast to maximum levels. |
| 4. | There is a large black or gray rectangle on the screen. | The TV’s analog closed captioning has been set to “text” mode in the Captions menu. Turn off because there is no text information being broadcast. |
| 5. | You cannot view a picture when playing a VHS tape. | Check your VCR’s owner’s guide for further troubleshooting. |
| 6. | VCR or DVD player’s on-screen menus jitter up and down. | Stop playback. Possible cause: Many VCRs and DVD players provide on-screen menus at only half-resolution that may appear to jitter up and down. |
| 7. | When viewing a stopped VCR, white lines are rolling on the screen. | • Turn off video mute for the VCR. |
| • Begin playing the tape. | ||
| • Change the VCR input from Line 1 to the VCR antenna input. | ||
| 8. | A color program appears as a black and white image, or the colors are dim, or the screen is black. | The PerfectColor color balance has been incorrectly set. Reset the PerfectColor balance. |
| 9. | Picture from an HDMI input is noisy (poor quality). | Upgrade a Category 1 (unmarked) HDMI cable to a Category 2 high-speed HDMI cable. |
| 10. | The image from a computer appears distorted when viewed on the TV. | • Normal TV operation. The TV does not correct distortion in the picture from a computer because the correction process may cut off the edges of the image. |
| • The aspect ratio may be wrong for the image. Press MORE and then 0 (FORMAT) to change. | ||
| Sound | ||
| 1. | There is no sound even when the volume is turned up. | • Check if the MUTE key is on. |
| • The TV’s “Listen to:” setting may be set to SAP (analog program from the ANT input) but no SAP is being broadcast. | ||
| • Check that the Speakers option is set to TV to hear sound from the TV speakers. Possibly sound is being sent to one of the audio outputs for an A/V receiver or headphones. | ||
| • If using an A/V receiver, check that the Speakers option is set to AV Receiver to hear sound from the A/V receiver speakers. | ||
| • Press and hold the POWER button on the control panel for 10 seconds to perform System Reset. | ||
| 2. | The sound does not match the screen picture. | The TV’s “Listen to:” setting may be set to SAP (analog program from the ANT input). |
| 3. | The sound from my A/V receiver does not match the screen picture (1 should hear the correct audio from my A/V receiver). | • Check that DIGITAL AUDIO OUTPUT and/or AVR AUDIO OUTPUT on TV’s main panel is connected to the A/V receiver. Without this connection, devices connected only to the TV (and not the A/V receiver) can be heard only from the TV speakers. Note that this includes the ANT input, a device (such as a camcorder) connected to the convenience panel, and any other device sending audio to the TV only. |
| • If using a NetCommand-controlled A/V receiver, NetCommand may be selecting the wrong A/V receiver audio input. Check the A/V receiver’s NetCommand setup in the Inputs > AVR menu. | ||
| 4. | Cannot select an audio-only device; it does not appear in the Activity menu. | Plug an unused video plug into the Y/VIDEO jack to activate Auto Input Sensing and make the audio device selectable in the Activity menu. |
| 5. | Sound is coming from the TV speakers instead of the A/V receiver. | Disconnect headphones. Connect the TV’s AUDIO OUT to the A/V receiver and select AV Receiver from the New Device Found screen. |
Mitsubishi UNISEN LT-40151 television troubleshooting
| Reset Name | When to Use | How to Use | Resulting Action |
|---|---|---|---|
| Format | When the picture shape seems incorrect, use MORE >0(FORMAT) to change the shape of the picture. | Press the MORE key and then repeatedly press 0 (FORMAT) to cycle through the available aspect ratios. | The last-used format for a signal type is memorized for each input. The next time the same input and the same signal type is viewed, the last-used format will be recalled. |
| PerfectColor™ Reset or PerfectColor™/ PerfecTint™ Reset (153 Series) (for the single input currently being watched) | When the color intensities seem out of balance, use the PerfectColor/PerfecTint reset to reset the color balances to the original factory settings. Both PerfectColor and PerfecTint are reset at the same time. | 1. While viewing the input to be reset, press MENU and go to Adjust > Picture > PerfectColor. | All PerfectColor/PerfecTint sliders are reset to the original center position. The PefectColor/ PerfecTint settings for other inputs remain unchanged. |
| 2. Press ENTER to display the PerfectColor adjustment screen. | |||
| 3. Press CANCEL to reset the colors. | |||
| A/V Memory Reset (for the single input currently being watched) | When audio and/ or video settings for a single input seem incorrect, use A/V Memory Reset to return the input to the original factory settings. | 1. While viewing the input to reset, press MENU and go to Adjust > Reset. | All Audio and Video settings for the individual input are reset except for the Listen To, Language, audio Balance, Closed Caption, and Advanced Picture settings. |
| 2. Press ENTER to highlight the Reset icon. | |||
| 3. Press ENTER again to reset. | |||
| A/V Reset (for all inputs) | To reset audio and video adjustments for all inputs to the original factory settings. | While viewing the TV, press the control-panel buttons ACTIVITY and VOLUME DOWN at the same time for at least two seconds. | All Audio and Video settings are returned to the original factory settings, including Listen To, Language, audio Balance, Closed Captions, and Format. |
| Channel Memorization | To erase and re-memorize channels on the ANT input. | 1. While viewing the TV, press MENU to display the main menu. | All previously memorized channels for the antenna input are erased and a new set of memorized channels is created. To add or delete individual channels |
| 2. Navigate to the lnitial> Channel menu. | |||
| 3. Press ENTER. | |||
| 4. Highlight the reception mode, e.g. Ant Air. | |||
| 5. Highlight Scan. | |||
| 6. Press ENTER to start channel memorization. | |||
| Lock Menu Pass Code | To change your Lock menu pass code | Allows establishment of a new code. | |
| Control-Panel Lock Release | To re-enable the control-panel buttons after activation of the Control-Panel Lock | Press and hold the ACTIVITY button on the control panel for ten seconds. If the TV is powered off, you can now press the POWER button to turn it on. | Allows the control panel to be unlocked if the remote control is misplaced. |
| Auto Input Sensing for HDMI | If the New Device Found screen does not appear when you connect an HDMI device. | 1. Disconnect the HDMI device. | The New Device Found screen will display. |
| 2. Delete the HDMI input in the Inputs > Name menu | |||
| 3. Power on and connect the new device. | |||
| System Reset | If the TV does not turn on or off, does not respond to the remote control or control panel buttons, or has audio but no video. | Press and hold the POWER button on the control panel for ten seconds. | The TV will turn off. Power on the TV and the green LED will flash quickly for about one minute. The changes you made most recently, before using SYSTEM RESET, may be lost. |
| TV Reset (IMPORTANT: Use this reset only if other troubleshooting has been unsuccessful.) | To reset all consumer accessible settings and all memories to the original factory defaults. Use TV Reset if the TV can respond to controls but TV behavior is abnormal. CAUTION: All owner performed setups and adjustments will be erased. | 1. While viewing the TV, press MENU to display the TV main menu. | The TV will start the initialization process and then turn off. Power on the TV and the front green LED will start flashing. All memory and settings outlined in this Owner’s Guide will need to be set again. |
| 2. With the main menu displayed, press number keys 1 2 3 to display the Reset menu. | |||
| 3. READ THE ON-SCREEN WARNING AND INSTRUCTIONS. | |||
| • If you do not wish to use this reset, press BACK or MENU to back out. | |||
| • If you do wish to use the reset, press ENTER to erase all memories and settings. |