Haier HL19KN1 Service Manual

The Haier HL19KN1 TV uses the MST721 chassis.

No, the Haier HL19KN1 does not support HDMI input.

Yes, the Haier HL19KN1 supports the Zoom function.

First, check the power supply by verifying the voltage at F1/3A for 12V. If it is not 12V, check F1 and the peripheral power supply. If F1 is damaged, check the power supply net following F1. If the voltage is normal but the TV still does not turn on, check the LDO components (U10, U13, U16, U18, U19, etc.) to see if they are working normally. If the LDO is damaged or the loader is in short circuit, you may need to change U1/MP1410ES-LF or D17/SK34A-SMA.

To troubleshoot a power supply issue, first check the voltage at F1/3A for 12V. If it is not 12V, check F1 and the peripheral power supply. If F1 is damaged, check the power supply net following F1. Next, check E33/470μF/16V for 5V. If the voltage is normal but high, check Pin No.4 of U1/MP1410-ES or change U1. If the voltage is normal but low, E33 may be damaged or the loader is in short circuit. Additionally, check the LDO components (U10, U13, U16, U18, U19, etc.) to ensure they are working normally.

To troubleshoot a display issue, start by ensuring the cable is correctly connected and tightly secured. If the cable is fine, inspect the LCD panel for any issues. If the LCD panel is okay, check the circuit of output and the CN2/Jack. If these components are fine, you may need to change the LCD or check the power supply for U5 and the clock circuit. If the problem persists, consider changing or repairing any damaged components or replacing the cable for the panel connector.

First, check if there is an audio input signal. If there is, ensure the volume is not muted and is set to an appropriate level. If the volume and mute settings are correct, check the output signal at CN11. If the signal is present, check the power supply at U3/TPA1517NE-pin7. If the power supply is greater than 11V, check the voltage at U3-pin8. If it is 9.2V or higher, check for audio signal input at U3-pin1,9 and audio signal output at U3-pin4,6. If the signals are present, check for audio signal output at U21-pin60,61. If the signals are present, check the audio input signal from the source (PC/SV/YPBPR:U21-pin53,54, SCAR:U21-pin56,57). If the signals are not present, check the audio source, reset it, and check the speaker. If the issue persists, check the circuit from U6-pin2,30 to U3-pin8 or if U6 has been damaged. If the circuit is fine, check the output circuit from U3 and CN23. If the issue is still not resolved, check U21-pin45 for 8V or consider changing U21. If the issue persists, check the net between the audio input jack and U21, the power supply circuit for U3, and the net between U21-pin60,61 and U3-pin1,9.

To troubleshoot the audio output circuit, first check the audio input signal at the source. If the signal is present, check the volume and mute settings. If the settings are correct, check the output signal at CN11. If the signal is present, check the power supply at U3/TPA1517NE-pin7. If the power supply is greater than 11V, check the voltage at U3-pin8. If it is 9.2V or higher, check for audio signal input at U3-pin1,9 and audio signal output at U3-pin4,6. If the signals are present, check for audio signal output at U21-pin60,61. If the signals are present, check the audio input signal from the source (PC/SV/YPBPR:U21-pin53,54, SCAR:U21-pin56,57). If the signals are not present, check the audio source, reset it, and check the speaker. If the issue persists, check the circuit from U6-pin2,30 to U3-pin8 or if U6 has been damaged. If the circuit is fine, check the output circuit from U3 and CN23. If the issue is still not resolved, check U21-pin45 for 8V or consider changing U21. If the issue persists, check the net between the audio input jack and U21, the power supply circuit for U3, and the net between U21-pin60,61 and U3-pin1,9.

If the picture is not centered, you should first check the R.G.B input signal for U5. If the signal is okay, check if the wave of Vsync and Hsync is correct. If both are okay, perform the 'Auto adjust' process. If the issue persists, perform the 'Reset' process on the menu.

If there is no signal input, first check the circuit of Vsync and Hsync. If the circuit is okay, ensure that there is a signal input. If the issue persists, perform the 'Reset' process on the menu or check if the input mode is supported.