USB-C Power Delivery (PD) promises convenient and fast charging for everything from smartphones to powerful laptops. So, it’s incredibly frustrating when you plug in your device expecting a quick top-up, only to find it charging at a crawl, or maybe even discharging! Troubleshooting slow USB-C charging is a common issue, but often it stems from simple compatibility mismatches or solvable problems rather than faulty hardware.
Before assuming your battery or device is failing, work through these common issues and fixes. This MTI Software guide provides a step-by-step approach to troubleshoot slow Power Delivery charging and get your devices juiced up quickly again.
Quick Checks: The Basics First
Sometimes the simplest things are overlooked:
Is Everything Plugged In Securely?
Ensure the USB-C cable is firmly connected to both the charger and your device. A loose connection is a common cause of charging problems (Result 2.1).
Try a Different Wall Outlet
Rule out issues with the power source itself by plugging the charger into a different wall outlet known to be working correctly (Result 1.3).
Restart Your Device
A simple reboot can often clear temporary software glitches that might be interfering with power management or PD negotiation.
Step 1: Investigate Your Charger (Power Brick)
The charger is a primary suspect when charging is slow.
Is it USB PD Compatible & Wattage Sufficient?
- PD Support: Not all chargers with a USB-C port support the Power Delivery standard required for fast charging many devices. Check the charger’s specs or markings for “PD” or specific voltage/amperage outputs. A basic 5W USB-C charger won’t fast charge anything.
- Wattage Output: Is the charger’s maximum wattage output high enough for your device, especially laptops? Using a 30W phone charger with a laptop that needs 65W will result in very slow charging (Result 4.1, 5.1). Check the charger’s specs against your device’s requirements. See: Choosing the Right USB-C Charger Wattage.
- Original Charger: While not always necessary, using the charger that came with your device (or one with matching specs from a reputable brand) often guarantees compatibility (Result 1.3).
Using a Multi-Port Charger? Check Power Distribution
If your charger has multiple ports, plugging in additional devices usually splits the total available wattage. Charging your laptop might slow down considerably if you also plug in a phone or tablet. Check the charger’s manual for its power distribution logic.
Try Another Known-Good Charger
If possible, test your device and cable with a different charger known to support the required wattage and PD standard. This helps determine if your original charger is underpowered or potentially faulty (Result 4.4, 5.2).
Step 2: Examine Your USB-C Cable
The cable is the crucial link and a frequent cause of slow USB-C charging.
Is it Rated for the Required Power (>60W Needs E-Marker)?
- E-Marker Chips in USB-C Cables Explained: Why They Matter for >60W Charging (April 2025)Standard USB-C cables are only required to handle up to 60W (3A). For charging above 60W (up to 100W or 240W EPR), you must use a cable specifically rated for 5 Amps and equipped with an E-Marker chip to communicate its capability. Using an underrated cable will bottleneck charging speed (Result 4.2, 4.3). Power Up Safely: Choosing Cables Rated for 100W & 240W EPR] and E-Marker Chips Explained.
Check for Physical Damage
Inspect the cable ends for bent pins, dirt, or discoloration. Check the cable itself for kinks, cuts, or frayed sections. Physical damage can impede both power and data flow (Result 1.1, 1.3, 5.1).
Is it the Right Type? (Data Speed vs. Power Rating)
While often related for high-end cables, a cable’s data speed rating (e.g., USB 2.0 vs USB4) is separate from its power rating. Some cheap cables prioritize only basic charging or USB 2.0 data and might use thinner internal power wires, potentially struggling with sustained high-wattage delivery (Result 4.3).
Test with a Different, Appropriately Rated Cable
Swap out the cable for another one you know is rated for the wattage your charger and device support. This is often the quickest way to identify a cable causing slow charge (Result 1.1, 3.2, 4.4).
Step 3: Inspect the Device & Port
The issue might lie with the device being charged.
Is the USB-C Port Clean?
Pocket lint, dust, and other debris are notorious for accumulating inside USB-C ports, preventing a secure connection. This is a very common cause of charging issues (Result 1.1, 1.2, 1.3, 4.4, 5.1).
- How to Clean: Power off the device. Use compressed air to blow out debris. If needed, gently use a non-metallic, thin tool like a wooden or plastic toothpick to carefully scrape out impacted lint. Do not use metal objects like paperclips or pins, as this can damage the port contacts.
Does the Device Port Support PD Input?
Check your device’s specifications! Not all USB-C ports on laptops or other devices are designed to accept Power Delivery input for charging. Some might be data-only or only support DisplayPort output. Look for PD or charging symbols next to the port.
Check for Physical Port Damage
Look inside the device’s USB-C port for any bent or damaged pins.
Step 4: Consider Device Settings & Usage
How you use the device while charging matters.
High Power Consumption? (Background Apps, Heavy Load)
If your laptop or phone is running intensive applications (gaming, video editing, multiple background processes) while plugged in, it’s consuming significant power. This reduces the net power going into the battery, making charging appear slower (Result 1.1, 1.2, 2.1, 2.2). Try closing unnecessary apps or charging the device while it’s idle or asleep.
Battery Health & Optimization Settings
- Battery Health: An old, degraded battery holds less charge and may charge slower (Result 1.2, 2.1, 2.2, 5.1). Check your device’s battery health status in its settings if available.
- Optimized Charging Settings: Many operating systems (iOS, Android, Windows, macOS) and manufacturer utilities have settings designed to prolong battery lifespan by slowing down charging speeds, especially after reaching 80%. Check these settings (often called “Optimized Battery Charging,” “Adaptive Charging,” etc.) and consider temporarily disabling them for testing purposes.
Thermal Throttling
Is your device or the charger getting excessively hot? Both devices and chargers have safety mechanisms that will slow down charging speed if temperatures get too high (Result 1.2). Ensure good ventilation and avoid charging in direct sunlight or hot environments.
Step 5: Check Software & Drivers
Software glitches or outdated drivers can interfere with PD negotiation.
Update Operating System (OS)
Manufacturers often include bug fixes and improvements related to power management and USB-C PD compatibility in OS updates (Result 1.1, 1.3, 2.2, 5.1).
Update Drivers & Firmware (Especially for Laptops)
Ensure you have the latest chipset drivers, power management drivers, USB drivers, and BIOS/UEFI firmware installed for your specific laptop model. Check the support section of your laptop manufacturer’s website (Result 5.1, 5.2, 5.4). Outdated firmware is a common cause of PD issues.
When It Might Be Hardware Failure
If you’ve systematically tried different known-good chargers and cables that meet your device’s specs, cleaned the ports, checked settings, and updated software, and charging remains consistently slow only on that specific device, there might be an issue with the device’s USB-C port, battery, or internal charging circuitry requiring professional repair (Result 4.4, 5.1). Similarly, if one specific charger or cable consistently fails across multiple devices, that accessory is likely faulty.
Conclusion
Slow USB-C charging can usually be resolved by systematically checking the components involved: the charger’s PD capability and wattage, the cable’s power rating and condition (including its E-Marker for >60W), the device’s port cleanliness and PD input support, device settings and usage, and finally, software/driver updates. By ensuring your charger, cable, and device are all compatible and meet the required USB Power Delivery specifications, you can typically restore the fast charging speeds you expect.
Need more info on USB-C? Visit The Ultimate Guide to USB-C. Understand wattage better: Choosing the Right USB-C Charger Wattage. Learn about cables: Cable Power Rating Guide and E-Marker Chips Explained.