Mazda Liftgate (Trunk) Won’t Close With Button | Easy Dealer Fix Explained

If your Mazda’s power liftgate won’t close when pressing the button, you’re not alone. Owners of the Mazda CX-5 (2017–2020), Mazda CX-30 (2020–2021), Mazda3 (2019–2022), and Mazda MX-30 (2022) have reported issues where the liftgate fails to operate, often after rain, condensation, or even a trip through a high-pressure car wash. The root cause is corrosion inside the power liftgate (PLG) rear switch connector, which can lead to malfunction or intermittent failure. In some cases, the system stores DTC B11C4:23 (Liftgate Lock Switch Circuit Malfunction) and may even contribute to battery drain. Mazda has addressed this problem in Technical Service Bulletin (TSB) 09-013/25, which is filed with the NHTSA under campaign number 11016214. This is a TSB, not a recall, meaning the fix is performed under warranty if you’re eligible, but it won’t be done automatically like a recall. The dealer procedure involves replacing the faulty switch with a redesigned, waterproof version and sealing the connector. If corrosion has already damaged the harness, a replacement pigtail is installed. Owners on forums and Reddit confirm that dealers are successfully repairing this issue, and many report smoother liftgate operation after the updated switch is installed. If you’re experiencing the problem, bring your Mazda to the dealer and reference TSB 09-013/25 so they can perform the fix. #Mazda #CX5 #CX30 #Mazda3 #CarRepair