Help! Macbook A1707 turn on without image..

[oemelectronic]

hi friend
i have Macbook A1707 820-00281 power but no imagen
PPBUS_G3H : 12.45volt
PP3V3_G3H : 3.20 volt
PP3V3_S5 : 3.24 volt
PP5V_S4 : 5.05 volt

phase coils 0.60 volt
please help friends

[mon2]

Re: Help! Macbook A1707 turn on without image..

Does the keyboard CAPS green light turn on / off?

Shine a flashlight to the display front and sides.

Can you see any graphics?

The A1707 has flexgate issues. Check the internet for more details.

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

hi dear thanks!!
no CAPS keyboard light
neither sides of the screen
..

[mon2]

Re: Help! Macbook A1707 turn on without image..

Can you perform the SMC reset upon power up?

Do you have a usb type C meter?

What is the voltage & current draw as shown with the type C meter?

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

hi dear
usb type c test: 19vot 1.4amp working mainborad

mainboard works take cpu temperature.
TODAY discover
the moment you turn on it has voltage PHASE COILS. The screen turns on, but after 5 seconds the phase coils voltage disappears and the screen turns off.
but the mainboard is still working fan and cpu

[mon2]

Re: Help! Macbook A1707 turn on without image..

That is a good sign on the current draw.

When the screen turns on - do you see the graphics ?

When the screen turns OFF, is it only the backlight is gone or the whole computer turns OFF? To test the backlight idea, apply a flashlight after the screen goes dark on the front face. Can you see the graphics ?

Moving forward, which phase coils lose the voltage ? Post their exact locations from the boardview files and the schematic.

Coils should be 'Lxxx' format.

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

hi dear
are flexgate issues
have picture. but it has another problem not WiFi
can't turn on wifi. will be software?

THANKS

[mon2]

Re: Help! Macbook A1707 turn on without image..

You may have flexgate issues but cannot be sure since you have the display visible with a flashlight.

For sure, your backlight is not ON.

Check and post the voltage readings for:

1) F8400, pin # 1. This should be PPBUS_G3H. Value ?

2) F8400, pin # 2. PPVIN_S0SW_LCDBKLT_FET. Value ?

3) PPVOUT_S0_LCDBKLT.

On the WIFI not working:

4) PP3V3_S4_WLAN_SW

5) PP3V3_S4_WLAN

6) SMC_WIFI_PWR_EN

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

HI DEAR MON2
video works now, it was flex problem
now i don't have wifi disabled, but ok bluetooth
here the values :

4) PP3V3_S4_WLAN_SW : 3.0VOLT

5) PP3V3_S4_WLAN : 3.2VOLT

6) SMC_WIFI_PWR_EN : 3.2VOLT

thanks

[mon2]

Re: Help! Macbook A1707 turn on without image..

How did you fix the flex problem? New display or replace the flex cables? Facing the same issue with a1707 820-00840 logic board.

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

Reflux connector solved video
Macbook A1707 820-00281 is logic.
no wifi today
thanks

[mon2]

Re: Help! Macbook A1707 turn on without image..

hi.

1) voltage of PP3V3_S4_WLAN_SW ?

2) check and post the voltages on the WIFI rom (see attached).

3) from the schematic, it appears that the bluetooth (BT) and WIFI functions are supported by the single module. That is, if BT is working then WIFI should be possible as well. Just that the BT and WIFI functions appear to have different and independent power rails.

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

hi dear MON2
happy year 2022 first

1) voltage of PP3V3_S4_WLAN_SW : 3.27VOLT
2) check and post the voltages on the WIFI rom (picture add) not have volt.
3). BLUETHOOTH WORKING. BUT NO WIFI
THANKS

[mon2]

Re: Help! Macbook A1707 turn on without image..

Hi. Happy New Year to you as well.

The Vcc is a good voltage to power the WIFI flash memory device.

However, no voltage on the SPI interface pins is odd. Perhaps others can comment on this area. Perhaps the SPI flash rom is only used during first power on and then no activity after the boot cycle?

If possible, try to measure or check for activity upon first power on.

Here a low cost logic analyzer could be helpful.

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

yes dear
please help friend

thanks

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

Hi. Happy New Year to you as well.

The Vcc is a good voltage to power the WIFI flash memory device.

However, no voltage on the SPI interface pins is odd. Perhaps others can comment on this area. Perhaps the SPI flash rom is only used during first power on and then no activity after the boot cycle?

If possible, try to measure or check for activity upon first power on.

Here a low cost logic analyzer could be helpful.

HI DEAR
It has something to do with it, I try it without connecting the lcd screen, because it is broken.

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

Hi. Happy New Year to you as well.

The Vcc is a good voltage to power the WIFI flash memory device.

However, no voltage on the SPI interface pins is odd. Perhaps others can comment on this area. Perhaps the SPI flash rom is only used during first power on and then no activity after the boot cycle?

If possible, try to measure or check for activity upon first power on.

Here a low cost logic analyzer could be helpful.

HI DEAR will this?
https://logi.wiki/index.php/T1_MacBo...IC_Replacement

NEED REMPLACE IC U3710

[mon2]

Re: Help! Macbook A1707 turn on without image..

Interesting link on WiFi details.

What does the WIFI screen show for your logic board?

Can you post the screen pic to compare with the linked page?

The reference page implies 3 devices must be replaced as they are paired.

The eeprom (flash) that has no voltage on the SPI pins is rather low density. It must be to store scanned access points, mac address, etc. Nevertheless, it is important.

[oemelectronic]

Re: Help! Macbook A1707 turn on without image..

Hi dear.
Add picture. Wifi working. But no search red