What Does This Error Mean?

Weak Keurig coffee is most often caused by a clogged needle not fully puncturing the K-Cup, or selecting too large a cup size. Clean the entry and exit needles, select 6 or 8 oz instead of 12 oz, and try a dark-roast Bold K-Cup.

Affected Models

Keurig K-Classic
Keurig K-Elite
Keurig K-Select
Keurig K-Supreme
Keurig K-Slim
Keurig K-Café

Common Causes

Clogged entry or exit needle not fully puncturing the K-Cup foil
Too large a cup size (10 or 12 oz) over-diluting the coffee
K-Cup past its use-by date or stored in heat or humidity — stale grounds
Strong brew or bold brew mode not enabled on compatible models
Scale buildup restricting water flow and pressure through the K-Cup

How to Fix It

Clean the entry and exit needles.

Use the Keurig orange needle-cleaning tool or straighten a large paper clip. Open the lid, locate the needle inside the brew head, and clear each hole with the tool. Also check and clear the exit needle at the bottom of the pod holder. Run two water-only brew cycles after cleaning.
Select a smaller cup size.

Choose 6 oz or 8 oz instead of 10 oz or 12 oz. Smaller cup sizes push less water through the same K-Cup, producing a stronger, more concentrated brew. For most K-Cup varieties, 8 oz is the intended brew size.
Enable Strong Brew mode.

On compatible models (K-Elite, K-Supreme, K-Café), press the Strong button before brewing. This extends the brew time, allowing more flavor to be extracted from the grounds. If your model does not have a Strong button, reduce the cup size as the equivalent adjustment.
Replace the K-Cup with a fresh one.

Stale, damaged, or expired K-Cups produce weak coffee. Check the use-by date on the K-Cup packaging. Ensure the foil lid on the K-Cup is intact — a pre-punctured or cracked K-Cup loses flavor before it even reaches the machine.
Descale the Keurig.

Scale inside the water path reduces water pressure through the K-Cup, resulting in under-extracted coffee. Run the full descale procedure from Settings > Maintenance > Descale. After descaling, test with a fresh dark-roast K-Cup at the 8 oz setting.

When to Call a Professional

Weak coffee is always resolvable through cleaning and settings adjustments. No hardware repair is needed for this issue.