Intermittent USB-C / USB-A issues + Trackpad Freezes — T14s Gen2 (11th-gen Intel) — Seeking Board-Level Advice

[iam5]

I’m looking for advice on board-level troubleshooting and potential component-level repairs for a Lenovo ThinkPad T14s Gen2 Intel (i7-1185G7) showing multi-domain instability. Hoping someone familiar with this platform (or the related X1 Carbon Gen9/Gen10, X13 Gen2, X1 Nano Gen1/2) can point me toward the right section of the board to inspect, and whether any of the known fixes apply. Symptoms:


1. Trackpad (CS21 module) intermittently freezes during active use

• Not tied to lid open/close
• External USB mouse continues working
• Sometimes recovers with sleep/wake
• Looks like an EC or I2C-domain issue

2. USB-C ports are unstable

• Devices drop power while in use
• Sometimes no detection when plugging anything in
• Happens on either port
• Not fixed by drivers, firmware, or OS power settings

3. USB-A instability

• Right-side daughterboard unplugged improves overall stability
• Suggests 5V power-gate or local power rail noise

Context:


This model is known to use the same PD controller / retimer architecture as the X1 Nano and X13 Gen2, and the behavior looks similar to the documented failures where:

• Cypress/Infineon PD controller partially fails
• Intel retimer weakens under heat
• EC 3.3V_S5 rail caps go marginal and introduce ripple
• USB power-gate MOSFETs partially fail
• Additional decoupling on EC rail improves stability

My Question(s):


I’m looking for guidance on:

1. Which components on the T14s Gen2 board commonly fail?
   • PD controller?
   • Retimer?
   • EC rail MLCC bank?
   • USB 5V power-gate MOSFETs?
2. If the EC 3.3V rail re-cap is applicable here, which MLCCs should be tested / replaced?
   • Same capacitance with better brands (Murata/TDK)?
   • Any known cluster that typically drifts out of spec?
3. Is the “add decoupling MLCCs” mod recommended on this board?
   • e.g., adding 10–22 µF + 0.1 µF to PP3V3_S5
   • Any preferred place to tap in?
4. For USB power-gate MOSFET failures, which part numbers does this board use, and are they known to go marginal?
5. If anyone has repaired this exact model, which component ended up being the root cause?
   
   
   Edit:
   Sorry, board is NM-D362 Rev 1.0

[viking6791]

From my experience, the solution comes from talking to people who want to share their experience, everyone has a different perspective on seeing things and that's why we are here.
So, to understand, ALL of the above are defects found by you and you want to know if anyone has encountered the same defects before?
I have repaired this type of device only once. I saved the three SPI memories for future interventions.
It is very important that the motherboard of this laptop is specified, otherwise the information may not always be true.


























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