I would think special test equipment is needed and at a minimum an oscilloscope. You could use the oscilloscope on Pins 23 and 24 to see if there is audio. However, that does not test the speakers or the circuitry (which could include the "small daughter board) which feeds the speakers and/or headphones. The schematics you have appear to be generic and not specific to your PC and how the output sound is actually routed. If there is audio on pins 22 and 23. Other than the use of a scope to check the output pins and possibly trace it through the PC I don't see much else you can test.
I believe you may find the fault within minutes If this laptop is with you but its 1000s kms away If i got valuable information I 'll be report back here. Thanks Fireberd for your help and sharing.
The owner of this laptop come and told me that the problem happened immediately after woofer jack insertion. Do audio main chip cx20752 or its circuits may got short? I have tried without audio jack port but no avail. Are some main audio components with this port?
I did a search for the part number DR15233DI but did not come up with anything. On SOME (not all) laptops a small board such as that has the sound chip and if it were defective replacing the part will fix it. However, I can't find anything on that part so I can't say for sure if it is the sound chip and associated circuitry.
Here this defected cx20752 IC display no symptoms in device manager and have no error report, windows cannot detect this dead IC except no sound. This was the problem that cause lots of confusions in troubleshooting and diagnosing.