A faulty speaker wire can cause a malfunction that halts insulin delivery, prompting the US Food and Drug Administration to classify the action as a Class I recall.
Tandem Diabetes Care has issued a medical device correction for certain models of its t:slim X2 insulin pumps due to a speaker wiring issue that can cause the device to fail. The wiring problem can trigger a “Malfunction 16” error, which stops all insulin delivery and makes the pump inoperable. The US Food and Drug Administration (FDA) has designated this a Class I recall.
According to the FDA notice, the sudden cessation of insulin delivery can lead to high blood sugar (hyperglycemia). Severe cases could result in serious adverse health consequences, including hospitalization. To date, 59 injuries related to this issue have been reported, with no reports of death.
The Correction Plan and User Guidance
The correction does not involve removing the pumps from use unless a malfunction has already occurred. Tandem Diabetes Care is developing a software update designed to enhance early detection of the speaker failure and will add persistent vibration alerts as an additional safeguard. The company will notify affected users when the software update is available.
In a letter sent to customers on July 22, 2025, Tandem advises users to continue using their pumps if a Malfunction 16 error has not occurred, but to have a backup method of insulin delivery available as directed by their physician. The company also recommends users enable push notifications on the Tandem t:slim mobile app to receive an alert if the malfunction occurs. If the error alert is received, users should immediately switch to their backup insulin method and contact Tandem to arrange for a replacement pump.
A full list of affected device models and serial numbers is available on the company’s website.
ID 156899170 © Ahmet Yamak | Dreamstime.com
