Dell Latitude 3490 no sound

[Oleksandr Dorogyh]

Hello everyone

I need some advice

boardview and schematic
https://www.badcaps.net/forum/troubl...6p-rev-1-0-a00

Bios updated to latest version (updated via bios update utility).

Windows: no sound, all drivers installed, device manager shows "High Definition Audio Device" without any error, there is red cross on sound icon, click on troubleshooting says that probably there is an error in speaker or headphone connection

Linux: no sound, lspci shows High Definition Audio

Audio in BIOS is enabled.
Beeping works normally.

On ALC3251 (had been replaced to new one) all voltages are present 1.8, 3.3, 5

On HDA_CODEC_BITCLK I see clk signal about 24 MHz

On HDA_CODEC_SDOUT and HDA_SDIN0 absolutely nothing from power on to loading windows desktop.

Can I assume than problem in CPU ?

Or I at least should try flash the bios with cleared ME ?

[mcplslg123]

Try de-soldering the audio jack for headphone.

[Oleksandr Dorogyh]

Try de-soldering the audio jack for headphone.

I tried and nothing happens.
Should be some communication between cpu and realtek chip.

I've ordered another motherboard will check behavior (communication) later.

[piernov]

https://www.badcaps.net/forum/troubl...roubleshooting

[mcplslg123]

The audio codec communicates with PCH and not CPU.

[rogfanther]

On some Dell, you need to remove & delete the audio driver it is using, and download the one from Dell.

[Oleksandr Dorogyh]

https://www.badcaps.net/forum/troubl...roubleshooting

thanks, I really forgot to check vendor and device ID. Only Intel (8086) audio device is present in Windows and Linux

The audio codec communicates with PCH and not CPU.

yeah, I know, It from local slang. As we call whole IC as "processor" or "combined processor" it is much closer to CPU abbreviation than to PCH

On some Dell, you need to remove & delete the audio driver it is using, and download the one from Dell.

Linux must found realtek and load realtek kernel module, but realtek had not appears in device list



I will try to check HDA signals on new motherboard tomorrow

[Oleksandr Dorogyh]

Now I can confirm that processor (pch) dont communicate with realtek chip. Probably I should reball the processor but currently I have no proprient equipment/tools for doing this, so fixing this MB will be postponed for future.

On new motherboard I see a lot of packets on HDA_CODEC_SDOUT before loading windows desktop I not checked behavior on linux as I am completely confident in diagnose now.

thanks a lot to all responders

[mcplslg123]

Your problem most likely lies in HDA_SYNC. There should be a N channel mosfet like 2N7002 on this line.Just replace it and see if the audio detects in device manager. Its not a PCH problem so just dont go for drastic steps.

[Oleksandr Dorogyh]

Your problem most likely lies in HDA_SYNC. There should be a N channel mosfet like 2N7002 on this line.Just replace it and see if the audio detects in device manager. Its not a PCH problem so just dont go for drastic steps.

There are only 33R resistors on HDA lines, I already check all of them many times.