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
2. USB-C ports are unstable
3. USB-A instability
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:
I’m looking for guidance on:
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
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
I’m looking for guidance on:
- Which components on the T14s Gen2 board commonly fail?
- PD controller?
- Retimer?
- EC rail MLCC bank?
- USB 5V power-gate MOSFETs?
- 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?
- 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?
- For USB power-gate MOSFET failures, which part numbers does this board use, and are they known to go marginal?
- If anyone has repaired this exact model, which component ended up being the root cause?
Edit:
Sorry, board is NM-D362 Rev 1.0