Missing 5V and can't read VCC of RT8206B

[orientalsniper]

Hello, I can't read anything in pin 3 (VCC) of RT8206B, I can read 3.3V but not 5V. What does this usually indicate? Is problem with RT8206B or is it something else?

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

I swapped with another RT8206B, I'm getting 5V in some pins, however pin 3 is 5V and pin 6 is 19V. BIOS and EC chip have no V readings.

[spidey]

Re: Missing 5V and can't read VCC of RT8206B

what is the motherboard code ? need to check from the schematic. usually if there is 3.3v and 5v is missing it is EC problem. check which signal enables 5v output.

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

It's a Dell N4110 (DA0V02MB6E1). After I flashed EC, laptop was able to turn on, but wouldn't post, so I went to flash BIOS, however, the traces came up and I had to do trace repair, then PQ19 was smoking, so I replaced it.

Now I'm measuring RT8206B and it has 3.3V and 5V, now BIOS lost 3V. I was so close to repairing this, any ideas?

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

Is it weird I'm getting 3.3V in pin 3,7,8 of the EC chip and 3.3V in all pins of BIOS chip but pin 4?

[highpulse]

Re: Missing 5V and can't read VCC of RT8206B

Since you have a lot of problem with 3.3 and 5 volts line , and now you mention you have lost voltage for the spi bios , have you checked the correct signal incoming from KB controller ? also if you can share here the schematic will be more easy to tell you some stuff to chek .
which are the values for LDO on the main Step controller ? also for the EN1 and EN2 pins , you should get around 5 volts ..

another things im curious its practically impossible having 3.3 volts on all pins of any of the bios SPI or EC . so double cheek with schematic if you are reading the correct chip.
Let us know and share here the schematic for we can help you out solving this

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

Hello, I don't have schematic of this board.

EC chip has 3.3V in pins: 3, 7, 8 and BIOS chip in pins: 1,2,3,5,6,7,8.

In RT8206B: LDO is pin7(5V), EN1 is pin14(3.3V) and EN2 is pin27(5V).

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

I think this is the schematic:

http://kythuatphancung.com/download/...chematics.html

[highpulse]

Re: Missing 5V and can't read VCC of RT8206B

ok opening the schematic now , i will re edit this post with a possible solution , let me chek

Tell me which is the identification for each bios chip ? Uxx??

chek voltages on U1 and U12 , its impossible you having on pin 4 of U12 voltage at all ..chek also if the U12 is the MX25L3205D...

Also the 3.3 volts on this PCH bios chip are 3.3 Run meaning that this voltage can only be present when you turn on machine and pass S5 state

Also you mention pq19 was burned, this is a controller to make 1.5v-sus to 1.5V_run

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

Hello, U12 is a W25Q32, U1 is a W25X80 (originally a W25X40).

The voltages are EC (U1) chip has 3.3V in pins: 3, 7, 8 and BIOS (U12) chip in pins: 1,2,3,5,6,7,8.

Sometimes when I replug DC adapter, BIOS loses all voltages. (0V)

[highpulse]

Re: Missing 5V and can't read VCC of RT8206B

For EC rom pins with 3.3V_alw pin 3 7 and 8 .. for PCH rom , you will have only voltages when you turn on the machine .

Do you notice PCH to get hot in any way ? or any place on board with hot temp ?

checking the schematic there is really nonsense , in having voltages on all pins of PCH bios ..alltough the PCH bios its different than the one mentioned on the schematic but even like this its impossible having voltage on pin 4 . so PCH might be dead . (attention PCH bios you can't reflash it with rom found on the brand site . you must find a good DUMP ROM site were you can get this rom you need to ref lash pch bios , but in any case , if you have 3.3 volts on the SPI part of the PCH bios , then its like PCH is sending you does values .REplace PCH and let us know

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

I notice no heat in the motherboard

Also, I downloaded BIOS from Dell website, it was a 5MB rom, so I dumped my EC and BIOS and used HxD to find starting offset and flashed with eeprom programmer. I don't think Dell BIOS'es are encrypted unlike HP, because I found relevant patterns.

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

The only weird thing is the laptop turned on when I flashed the EC chip just not POSTing, shit hit the fan when the traces of BIOS pin 2, 5, 6 were damaged, so I retraced it after BIOS reprogramming.

[highpulse]

Re: Missing 5V and can't read VCC of RT8206B

nooooooooo , SPI KBC ROM flash info , its entirely not the same as PCH bios . so if you flashed it with what you have found on website brand , than you must find the correct rom on a good bios dump SITE.
the bios we usually find on website brand like hp , dell toshiba etc , are for KBC ONLY . never for PCH or VIDEO CARD.

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

mmmmmm, does that explain the 3.3V in PCH BIOS?

[highpulse]

Re: Missing 5V and can't read VCC of RT8206B

hum , well im not entirely sure , but since machine architecture work on hexadecimal and binary , it could be a possibility , worth a try ! let us know the result

[orientalsniper]

Re: Missing 5V and can't read VCC of RT8206B

I can't find it. Bumping in case someone does.

[bishnu]

Re: Missing 5V and can't read VCC of RT8206B

please check ITE (IO) pin 127 to rt8206b pin n 25 conection I THINK SOLVE YOUR PROBLEM

[raihan]

Re: Missing 5V and can't read VCC of RT8206B

n4110 bios