Hp gaming 16 dag3jbmb8d0 rev d

[mcplslg123]

Mb as mentioned in the title. Totally dead and no dc jack light.
19V passes on to CLR correctly and dc-in fet biasing is correct. The only voltage present in mb besides 19V is 5V on coil and 3V is not there on coil(AWV IC). Enable is missing on pin12(Resistance to GND over 20 Kohms) of this IC for 3V and if i apply enable 3V is generated on coil but still no dc jack light.
When original 150W adapter is used,no voltage on AD_ID while if i use my 10A dc supply with HP PS_ID connector,AD_ID is 0.36V.
Flashed Main bios from HP website,extracted EC bios from main and flashed SIO IT5570-256(firmware size is 128KB however). It reads,writes and verifies correctly.
Resistance to GND on all coils checked and vcore area resistance is 1.4 ohms and GPU resistance to GND is 0.2 ohms which seems correct to me. Ram coil shows over 100 ohms with ram. cant identify all the coils as there is no schematic and/or boardview.(I've made a request for same in the sub forum).
With dc supply when try to turn on,dc jack light blinks white 3-4 times. I even tried putting 330K resistor between +19V and AD_ID(in that case AD_ID is 0.41V but still no dc jack light and dead.

Consumption when dc supply plugged goes to 14mA and then drops to 08mA.

Now i'll proceed in deeper probing SIO.The SIO used is IT5570-256 and i do have IT5570-128 with me.Can they be exchanged if i find something abnormal with SIO?.
In the meantime,has anyone faced similar problem on this platform or any other ideas?

PS: No one seems to have worked on the mb earlier and there is no corrossion,liquid spill. 3V LDO is present

[piernov]

AD_ID is most likely too low. Try with a much lower resistor value.
IT5570-256 vs. IT5570-128: seems like different internal Flash size.

[piernov]

For reference, resistor in 230W power brick with black tip is 100k.

[mcplslg123]

Thanks@piernov for your response. IT5570-256(seems like internal flash size 256kb) and IT5570-128(seems like 128kb). I noticed this and thats why raised the question as firmware used is actually 128KB.
I'll try with a lower resistor and report back.

[mcplslg123]

Tried with 120K/150K-still no dc jack light. AD_ID with 150K is 0.86V. Just lifted the SIO and i can see some oxidation.Some tracks are not in perfect shape.All this oxidation is beneath the SIO.From outside it was looking as good as new.

Will update once i shine up the tracks under my microscope and solder the SIO back.

[mcplslg123]

Finally success. It was the oxidation on track for pin107 of SIO. Got display.

A couple of points which may help other members as no schematic/bdv is available till date.

01.Only 5V is present on coil in standby mode. 3V wont be present on standby
02.AD_ID should be close to 0.8V
03.Resistanace to GND on PCH coil is 29.4 ohms(located next to 5V coil.
04.Resistance to GND on CPU coil is 1.4 Ohms and on GPU its 0.2 Ohms.
05.SIO used is IT5570-256 but has 128kb firmware.
06.SIO pin 58 to 63 must be 3.3V in standby for programming it.