2 Electrical switch & relay parts are listed for the 2021 BMW 440I, in 2 part types, covering the 3.0L L6 Turbocharged engine. Each one has a brand, a manufacturer part number and notes that say where it fits.
The switch and relay system on the 2021 BMW 440I covers the switches, relays and flashers that route power to everything the driver touches. All 2 listed parts are Brake Light Switch (1 part) and Power Window Switch (1 part).
Every part on this page is matched to the 3.0L L6 Turbocharged — the only engine offered in the 2021 BMW 440I.
The most listed brands for 2021 BMW 440I electrical switch & relay parts are DORMAN (1 part) and MARELLI (1 part).
Each part number listed for the 2021 BMW 440I opens a page with every vehicle that part fits.
Brake Light Switch
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| DORMAN | 920458 | 🇲🇽 MX | View on Amazon |
This table covers the pedal-mounted switch that turns on the brake lamps. Typical signs include a function that works intermittently, or a click without the accessory coming on. Inspect the connector behind the switch; heat-damaged terminals will kill the new part too.
This group shows a single part: DORMAN 920458.
Power Window Switch
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| MARELLI | CI51063 | 🇲🇽 MX | Front Left | View on Amazon |
This table covers the switches that command each window motor. Typical signs include a function that works intermittently, or a click without the accessory coming on. Inspect the connector behind the switch; heat-damaged terminals will kill the new part too.
This group shows a single part: MARELLI CI51063.
Buying Electrical Switch & Relay Parts for a 2021 BMW 440I
On this vehicle, the switch and relay system covers the switches, relays and flashers that route power to everything the driver touches.
- Confirm you have the 3.0L L6 Turbocharged engine — every part on this page is matched to it.
- Read the notes on each row for position, trim and spec qualifiers before you order.
- Where labor overlaps, inspect the connector terminals behind any failed switch — heat damage there will kill the new part too.
- Cross-reference the manufacturer part number against your old part or a service-manual listing.
Start with the largest groups on this page: Brake Light Switch and Power Window Switch .
Frequently Asked Questions
How many electrical switch & relay parts fit the 2021 BMW 440I?
Our catalog currently lists 2 electrical switch & relay parts for the 2021 BMW 440I across 2 subcategories and 2 brands, covering the 3.0L L6 Turbocharged engine. Each part is matched to the engine(s) it fits.
What are the signs of electrical switch & relay problems on a 2021 BMW 440I?
Common symptoms include accessories that work intermittently, a click without action, or one function dead while its fuse tests fine. If you notice any of these, identify the affected subcategory above and cross-reference the part numbers listed.
What should I replace at the same time?
Where labor overlaps, inspect the connector terminals behind any failed switch — heat damage there will kill the new part too.
What do the market flags (US, CA, MX) on each part mean?
They show the market for which the manufacturer published application data for that part — where the vehicle was first sold, not where the part was made. If your 2021 BMW 440I was originally sold in the US, the safest choice is a part marked for the US market.
How do I make sure a part fits my 2021 BMW 440I?
Every part on this page is matched to the 3.0L L6 Turbocharged engine. Then swap a suspect relay with an identical known-good one from the fuse box before buying — it is the fastest diagnostic there is. The notes column carries position and trim qualifiers where they apply.
Other Parts for the 2021 BMW 440I
Electrical Switch & Relay Parts for Other BMW 440I Years
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Manufacturer names, model designations and part numbers are used for identification and fitment reference only. AutoFactsDB is an independent catalog and is not affiliated with, endorsed by, or sponsored by any vehicle manufacturer displayed on this page.