BMW Coolant Thermostat Unit – Genuine Part 11538642

Description BMW Engine Coolant Thermostat Assembly (Heat Management Module) OEM Replacement – Part Number 11538642559 Fits BMW Models with B58 / B58B30 Engines (2019–2026)   Upgrade your BMW’s cooling system with this OEM-spec Heat Management Module (Coolant Thermostat Assembly). This unit is manufactured to match BMW’s original design specifications but is not a Genuine BMW-branded part. It offers precise control of coolant flow for modern B-series engines and restores proper temperature regulation for optimal engine performance. This OEM unit includes the required sealing O-rings and gaskets for installation.  Key Features OEM-Spec Replacement – Matches the function and design of the original BMW part Not Genuine BMW – Third-party manufactured to OEM standards Includes O-Rings & Gaskets – Ready for installation Precision Temperature Control – Supports rapid warm-up and efficient cooling Designed for BMW B58/B58B30 Engines Direct Fit Replacement NO WARRANTY PROVIDED UNLESS FITTED BY RMI APPROVED WORKSHOP Product Description This Heat Management Module (HMM) is an electronically controlled coolant thermostat used in BMW’s B-series engines. Instead of a simple open/close valve, it uses a rotary coolant control valve that adjusts flow dynamically for precise heat regulation. Common Symptoms of Failure Engine overheating Engine running hotter than normal Long warm-up time Cooling system fault messages Diagnostic codes: 20F220, 20F206, 20A704 Replacing a faulty HMM restores correct coolant circulation and helps prevent engine damage. Vehicle Compatibility BMW X5 (G05) – 2019–2023 xDrive40i (B58B30M0) sDrive40i (B58B30M0) xDrive45e (B58B30M1 – PHEV) BMW X7 (G07) – 2019–2022 xDrive40i (B58B30M0) BMW 540i / 540i xDrive – 2020–2023 RWD & AWD Gas and Mild Hybrid versions Engines: B58B30M0 / MHEV BMW 740i / 745e – 2020–2022 740i / 740i xDrive 745e PHEV BMW 8 Series (840i / 840i xDrive / Gran Coupe) Models 2020–2026 Coupe, Convertible, Gran Coupe B58B30M0 engines BMW M340i / M340i xDrive – 2020–2024 B58B30O1 engines RWD, AWD, and MHEV models BMW X3 M40i – 2020–2024 B58B30O1 BMW X4 M40i – 2020–2025 B58B30O1 BMW X6 40i – 2020–2023 B58B30M0 engines BMW Z4 M40i – 2020–2026 B58B30O1 engines BMW M240i / M240i xDrive – 2022–2025 B58B30O1 / B58B30M0 engines Package Includes 1 × OEM Engine Coolant Thermostat Assembly (Heat Management Module) Included: O-rings & gaskets Important Notes This is an OEM replacement, NOT a Genuine BMW part Professional installation is recommended to activate warranty Always verify fitment using your vehicle’s VIN