Description
Overview
Delphi BSM B2 engine fuse and relay box for PSA Citroën and Peugeot vehicles. Compatible with part numbers 9646405180 / 6500.Y1. This is a used part offered with a functional guarantee. Some plastic mounting tabs may be damaged; this does not affect electrical operation.
Function And Symptoms
The BSM (Boîtier de Servitude Moteur) is the engine-bay fuse and relay box that distributes power to key circuits such as the fuel pump, radiator fan, headlights and wipers. Typical symptoms of a failing BSM include intermittent electrical faults, non-functioning fuel pump, continuously running cooling fan or lighting outages. Replacing the unit with the correct BSM B2 and matching part numbers usually resolves these issues.
Fitment And Installation
The module is installed in the engine bay near the battery. Replacement is typically plug-and-play: disconnect the negative battery terminal, release any fuse/connector locks, unplug multi-pin harnesses, remove the old module from its bracket and fit the replacement. Ensure all connectors are fully seated before reconnecting the battery. In most cases no coding or pairing is required; correct type and product code are decisive for compatibility.
Durability And Failure Causes
BSM failures are commonly caused by water ingress, corrosion on pins, thermal cycling or internal relay/fuse wear. There is no fixed replacement interval; inspect and service when electrical anomalies appear. Check connector condition, fuse/relay layout and mounting hardware during replacement.
Technical Information
Manufacturer: Delphi
Model: BSM B2 (Engine Fuse/Relay Box, Engine Bay Location)
Product Codes: 9646405180, 6500.Y1, 6500 Y1
Additional Numbers: Marking On Cover/Label – BSM B2 (PSA)
Notes For Buyers
Always confirm compatibility by matching the part numbers, BSM variant (B2), connector count/shape and the fuse/relay layout with your vehicle. Suitable for selected Peugeot 206 and 307 versions when numbers match. If in doubt, compare the original unit visually and check the codes before installation.
