Lenovo T400_no power on_mainboard faulty

Collapse
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • DepRpd
    New Member
    • Feb 2022
    • 2
    • Romania
    #1

    Lenovo T400_no power on_mainboard faulty

    Shorted mosfet (the first one after power connector):
    Q34 SI4435BDY
    and cracked cap (near of the fet):
    C697 4.7UF 10% X7R 25V 3216. (they are four in the same place)

    If no fet available_ I have used one from the secondary battery port
    Q9 TPC8111 - is equivalent.
    Attached Files
    Last edited by DepRpd; 02-08-2022, 08:59 PM. Reason: ad picture
    Tags: None
    Previous template Next

    Related Topics

    Collapse
    • coasterghost
      Lenovo T14 Gen 2 Type 20XK Model 20XK0069US Odd Charging Issues
      by coasterghost
      For Badcaps Readers, Please note that I am hopefully going to present this same message to Lenovo to see if they have any insight to the matter as well and figured to share the entirety here for clarification. The System is out of warranty as it is but does have the option to have it extended.

      Model Information: T14 Gen 2 (Type 20XK, 20XL) Laptop (ThinkPad) - Type 20XK - Model 20XK0069US
      Board: T14 Gen 2 (Type 20XK, 20XL) - Type 20XK.

      System Hardware:
      Processor: AMD Ryzen 7 PRO 5850U
      Memory: 1x 16GB DDR4 3200 (Soldered on Board); 1x Crucial 32GB DDR4...
      09-08-2025, 10:46 PM
    • nrj1982
      Lenovo Ideapad3 NM-C821 faulty motherboard
      by nrj1982
      Hello all,

      I have a Lenovo Ideapad3 laptop, that has recently stopped working. When pressing the power button, the led is going on, but nothing else is happening.

      I have checked the 3.3V, 5V and 20V - all of them seem present (checked with multimeter and oscilloscope in order to verify that they are stable).
      I have checked the voltages around PU1901 - 0.9V, 1.8V, 5V, 2.5v, 0.6V and 1.2V - all of them are present.

      Now going further in the debug, I found that the CPU voltages produced by RT3662AC (PU5901) PWM driver are missing. I can see that the 20V...
      10-04-2025, 10:08 AM
    • AYsys
      Lenovo Yoga X1 Gen4 - Faulty Bios or what is going on?
      by AYsys
      Hello dear forum members,

      I own two Lenovo Yoga X1 Gen 4 laptops. One of them had a touchscreen problem, and I tried to fix it by externally flashing the BIOS. Unfortunately, I didn’t save the original BIOS and accidentally flashed it with a faulty one. After that, the device stopped working completely.

      I then had the idea to make a BIOS backup from the other Yoga X1 Gen 4 (same hardware) and flash it onto the non-working device.
      Nothing was flashed here — the BIOS was only backed up.

      I created the backup using a CH341A Black programmer and NeoProgrammer....
      09-13-2025, 11:05 AM
    • Document Archive
      Lenovo 3000 Series Schematic
      by Document Archive
      Lenovo 3000 Series Schematic

      Lenovo 3000 was a line of low-priced notebook and desktop computers designed by Lenovo Group targeting small businesses and individuals. It was replaced with the IdeaCentre and IdeaPad brands.

      3000 C100 laptop with Braille keyboard
      Lenovo 3000 C
      C100, C200 - 15-inch XGA screen
      Lenovo 3000 N
      N100, N200 - 14.1-inch- and 15.4-inch- WXGA models
      N500 - 15.4 inch screen.
      Lenovo 3000 V
      V100, V200 - 12.1-inch WXGA models
      Lenovo 3000 G
      G400, G410, G430, G450, G455, G510, G530, G550, and G560...
      10-04-2024, 06:05 AM
    • Document Archive
      Lenovo IdeaPad 120S Notebook 100 Specification for Upgrade or Repair
      by Document Archive
      This specification for the Lenovo IdeaPad 120S Notebook can be useful for upgrading or repairing a laptop that is not working. As a community we are working through our specifications to add valuable data like the 120S boardview and 120S schematic. Our users have donated over 1 million documents which are being added to the site. This page will be updated soon with additional information. Alternatively you can request additional help from our users directly on the relevant badcaps forum. Please note that we offer no warranties that any specification, datasheet, or download for Lenovo IdeaPad 120S...
      09-06-2024, 06:40 AM
    • Loading...
    • No more items.
    Working...