Core Ultra 200V (Lunar Lake) - USB-C PD Controller Latch-up (20V/0A) after High Power State (PL2)

[Silentmanbr]

Hello Intel Community,

I am reporting a persistent Power Delivery (PD) handshake failure on a Core Ultra 288V system (Acer Aspire 14 AI - A14-52MT). The issue seems to be a logic "latch-up" in the integrated USB4/PD controller triggered by disconnecting the power source during high-load scenarios.

System Specifications:

CPU: Intel Core Ultra 288V (Lunar Lake)

OS: Windows 11 Pro 25H2 (Build 26200.6584)

BIOS/EC: Version 1.32

Drivers: Latest Intel Serial IO and Intel Dynamic Tuning Technology (DTT) installed.

The Issue:
The laptop handles USB-C charging perfectly under idle or light office workloads. However, the charging controller fails consistently under the following scenario:

The system enters a high-performance state (Gaming/Stress Test) for 5+ minutes (PL2 state).

The USB-C charger is disconnected while the load is still active.

Upon reconnecting the charger (same unit or a different high-wattage PD source), the laptop refuses to draw current.

Technical Observations (using USB-C Voltmeter):

Negotiation: The charger successfully negotiates the 20V profile.

Current: Draw remains at 0.00A.

Persistence: A standard Windows 'Restart' does NOT clear the error. Only a full S5 Shutdown (Cold Boot) resets the controller logic and allows the system to draw power again.

Thermal Factor: Waiting for the system to cool down does not resolve the 0A draw; only a power cycle of the EC/PD controller works.

Comparison:
A user with a similar Lunar Lake Swift model reported no issues, but it is unclear if the test was performed under identical PL2 load conditions. This suggests either a specific power sequencing bug in the Aspire firmware or a widespread issue in how the Lunar Lake PD controller handles abrupt disconnects during peak power draw.

Question:
Is there a known errata or a specific Intel CSME/PMC or UCSI firmware update addressing PD handshake stability for the 200V series during power state transitions?

Any technical insight would be appreciated.

[JeanetteC_Intel]

Hello Silentmanbr,

Thank you for posting in Intel Communities.

Let me check on this on this and I will post an update once it's available.

Best regards,

JeanetteC.

Intel® Customer Support Technician

[JeanetteC_Intel]

Hello Silentmanbr,

Thank you for sharing your detailed technical report regarding the persistent Power Delivery handshake failure on your Core Ultra 288V system. Your analysis of the USB4/PD controller "latch-up" issue that occurs when disconnecting power during high-load (PL2) scenarios is very comprehensive.

This appears to be a sophisticated power controller state machine issue that may require escalation to our platform engineering team for firmware-level analysis.

To help investigate this potential controller/firmware issue, I'll need the following key information:

• When did you first encounter this issue? (from initial setup or after specific updates)
• How consistently can you reproduce this behavior? (every time, specific conditions, etc.)
• I could see that you already have the latest BIOS firmware. Has this issue observed with the previous firmware?

• What specific USB-C charger models/wattages have you tested?
• Have you tried different USB-C cables to rule out cable-related issues?

• Share your SSU (System Support Utility) log file to capture complete system configuration, including current CSME/PMC firmware versions and UCSI driver details
• Windows Event Viewer logs around the time of PD failure (System, Hardware Events, USB logs)

• What applications/stress tests reliably trigger the PL2 state?
• Does the issue occur at specific CPU package power thresholds?

• Current power management and USB-C/Thunderbolt settings in BIOS
• Any relevant EC (Embedded Controller) settings

This information will help determine if this requires firmware investigation or if there are known workarounds available.

Looking forward to your reply.

Best regards,

JeanetteC.

Intel Customer Support Technician

[Silentmanbr]

Hello JeanetteC,

Thank you for the professional and technical follow-up. Here is the accurate data regarding my environment, logs, and testing results:

1. Incident & Reproducibility:

Occurrence: Since day one (initial setup).

Consistency: 100% reproducible when the system is under PL2 load (>30W) and the charger is disconnected.

Previous Firmware: The unit arrived with BIOS 1.32. Previous versions were not tested as they are not available for rollback.

2. Hardware Environment (Tested Units):

Setup A: Original Acer 65W USB-C Charger (integrated cable).

Setup B: Samsung 60W USB-C Power Adapter paired with a Baseus 240W-rated USB-C cable (with E-marker).

Observation: The behavior is identical across both setups. A USB-C Power Meter confirms that upon reconnection, the handshake negotiates 20V successfully, but the current draw remains locked at 0.00A.

3. Logs & Telemetry:

Intel SSU: Attached to this post (SSU_Log.txt).

Windows Event Viewer: Attached (Logs_Kernel.txt).

Observation: While no explicit UCSI timeout errors were found, I identified several Kernel-PnP errors at the exact timestamps of the charging failures. This suggests that the Plug and Play manager is losing communication with the power controller or the USB-C subsystem during the PL2 state transition.

4. Power State Analysis (The "25W Threshold"):

Applications tested: High-demand titles such as Cyberpunk 2077 and Assassin's Creed Origins, which consistently push the SoC into the PL2 state.

Key Finding: I have isolated the trigger point using ThrottleStop. If I manually limit PL2 (Short Power) to 25W, the charging system works flawlessly during disconnect/reconnect cycles, even while running these games. However, at the factory 30W-37W range, the PD controller consistently fails upon disconnect. This strongly points to an EDP (Electrical Design Point) transition failure.

5. BIOS/EC Context:

Settings: BIOS V1.32. "USB/TBT support from S4" has been toggled with no effect on the bug.

Reset behavior: Only S4 (Hibernation) or S5 (Full Shutdown) resets the Embedded Controller and restores charging. Warm boots (Restart) do not clear the state.

I am attaching the requested logs to this reply. I hope this helps the engineering team identify the root cause in the PD state machine.

Best regards,

Marcos

[JeanetteC_Intel]

Hello Silentmanbr,

Thank you for the update and log files you've shared.

For transparency, I want to mention that since you're using an Acer laptop (OEM system), our support scope may have some constraints due to manufacturer-specific customizations, drivers, and configurations. Despite these potential limitations, I'm dedicated to providing the best assistance possible for your situation.

I'll move forward with further analysis and will update you once I have more information.

Best regards,

JeanetteC.

Intel Customer Support Technician

[JeanetteC_Intel]

Hello Silentmanbr,

We have checked and confirmed no documented Intel Errata or Firmware Updates related to this issue. For this said, it is highly recommended to:

1. Verify if Acer has released any BIOS/EC firmware updates specifically addressing USB-C PD controller stability on Lunar Lake platforms.

2. Reach out to Acer directly to confirm this matter, as this appears to be related to one of the following potential causes:

• Firmware Bug: PD controller firmware may not properly handle abrupt disconnection during high-power states
• Hardware Design Issue: Insufficient power sequencing protection during PL2→battery transition
• UCSI Driver Issue: USB Type-C Connector System Software Interface may have timing issues with rapid power state changes

3. Update the driver by choosing one of these methods: automatic update using this link, or visit your computer's manufacturer website to download

Important Note: This type of issue is typically managed by the computer OEM/ODM (Acer in this case) since they customize and control the system implementation.

Additionally, please let us know if you already contacted Acer regarding this issue and, if so, what response did you receive? This information will help determine the next appropriate steps.

Looking forward to your reply.

Best regards,

JeanetteC.

Intel Customer Support Technician

[JeanetteC_Intel]

Hello Silentmanbr,

Were you able to check the previous post? 

Let us know if you have any questions. 

Best regards,

JeanetteC.

Intel Customer Support Technician

[Silentmanbr]

Hello JeanetteC,

Thank you for the investigation. Since there are no documented Intel Errata yet and Acer has not provided a specific firmware fix, I will manage the situation using the workarounds I discovered (using Hibernation to reset the EC handshake).

However, I would like to leave a final technical observation for your engineering team:

The Core Ultra 9 288V is a high-end, low-volume SKU compared to the Ultra 5 or 7. I strongly suspect this PD latch-up during PL2 transitions is a platform-level issue that hasn't been widely reported simply because there are very few laptops with this specific 288V configuration in the hands of power users yet. As more Ultra 9 units hit the market and are pushed to their 37W PL2 limits, I expect similar reports to surface.

I've done my part in isolating the 25W threshold and the EDP failure. You may close the case for now, but I hope this data serves as a reference for future Lunar Lake power management patches.

Best regards,
Silentmanbr

[JeanetteC_Intel]

Hello Silentmanbr,

Thank you for your thorough investigation and detailed technical observations. I appreciate the effort you put into isolating this issue, particularly identifying the 25W threshold and EDP failure patterns.

We conducted an internal review and found no similar reports for this specific issue. Your analysis about the Core Ultra 9 288V being a low-volume SKU and the potential for more reports as units reach power users has been forwarded to our engineering team.

We recommend coordinating with Acer for further assistance, as this may be related to the laptop's power delivery design. Your hibernation workaround shows good problem-solving.

If Acer determines this is an Intel hardware issue, they can submit a ticket directly to us for further investigation.

I'll close this thread as requested. Your detailed analysis will serve as valuable reference material for our engineering team for future Lunar Lake power management considerations.

Thank you for your comprehensive technical contribution. For future assistance, please submit a new question as this thread will no longer be monitored.

Sincerely,

JeanetteC.

Intel Customer Support Technician