Low Output Warning
Anker Power Bank
Severity: MinorWhat Does This Error Mean?
Anker power banks enter low-current mode (around 0.5A) automatically when they detect a small device like earbuds or a smartwatch. For phones and tablets, press the power button once to exit low-current mode and deliver full charging speed.
Affected Models
- Anker PowerCore 10000
- Anker PowerCore 20000
- Anker PowerCore III
- Anker 737 (PowerCore 24K)
- Anker Nano Power Bank
- Most Anker power banks
Common Causes
- Small device detected (earbuds, smartwatch) — power bank reduced output automatically
- Phone drawing very low current while screen is off and battery is nearly full
- USB cable too thin to carry full current — causing the bank to see low draw
- Damaged or charge-only cable limiting current flow
- Power bank battery critically low — output reduced to preserve remaining charge
How to Fix It
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Press the power button once.
Most Anker power banks toggle between standard mode and low-current mode with a single button press. This forces the bank to re-detect the connected device and switch to full output.
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Try a thicker, high-quality USB cable.
Thin or charge-only cables have high resistance and limit current draw. Use the cable that came with your phone or a USB cable rated for at least 3A. A good cable alone often resolves low-output issues.
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Unplug and reconnect the device.
Disconnect the device completely, wait 5 seconds, and reconnect it. The power bank re-detects the device type on each connection and may correctly identify it as needing full output.
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Check the power bank's remaining charge.
When the power bank's battery is very low (one LED lit), it reduces output to extend the last bit of charge. Recharge the power bank fully and test again.
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Test with a different device.
Connect a phone that clearly needs charging. If the power bank delivers full speed to the other device but not the original one, the issue may be the original device's charging circuit or cable, not the power bank.
When to Call a Professional
If the power bank delivers low output even with a quality cable and a phone that needs a full charge, the output port circuitry may be degraded. Contact Anker support.
Frequently Asked Questions
Anker power bank charges my earbuds fine but barely charges my phone — why?
The power bank detected the earbuds' low current draw and switched to low-current mode. When you connected the phone, it stayed in that mode. Disconnect everything, wait a few seconds, connect only the phone, and press the button once to force full output.
How do I know if my Anker is in low-output mode?
In low-current mode, the charging speed on your phone will appear very slow (often showing 'Charging slowly' on Android). Some Anker models flash the LED in a specific pattern. Press the power button once to exit the mode.