BMW Electrical Sensors, Switches, & Relays for BMW E90 M3 S65 4.0L

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Electrical gremlins can be very frustrating. Luckily your BMW's electrical system is better than most, even if it's 25 years old. Here you will find electrical relays, sensors, switches, and modules for the engine, camshaft, and crankshaft. Our parts are OEM, Genuine BMW, or approved aftermarket brands that we have an excellent track record with. There is no middle ground with electrical parts - it either works perfectly or not. And there's nothing more frustrating than a new part that fails right out of the box. So it's important to choose quality replacement parts over a cheap but faulty piece.

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Braille Lightweight Advanced AGM Battery - B3121 - 21lbs
Braille Lightweight Advanced AGM Battery - B3121 - 21lbs
Braille - Corporate Logo
T#:558042
Part#: B3121
Ships in 6 Business Days
$ 270.99 USD
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$ 270.99 USD
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When building a car for the track, one of the most important factors to consider is weight. Stock batteries can weigh up to almost 50 pounds and are unnecessarily large, designed to power a host of systems not normally used in a track car (radios, lighting, etc.). What can you do to cut weight the weight without affecting your car's operation? This is where Braille Battery comes in with their long line of performance lightweight battery options! Designed to provide the highest cranking power possible while being up to 75% lighter, Braille Battery is one of the foremost leaders in automotive racing batteries with nothing but high quality, high output batteries in mind! The B3121 battery from Braille is their lightest do-everything battery available, offering 1380 pulse cranking amps that can crank over V8 engines with ease while still coming in at under 22 pounds, half of the weight of a standard Group 34 battery! This is thanks to their Advanced AGM racing technology that allows them to put a ton of power into a very small package. Physical Specifications: BCI Group: All sizes Weight: 21lbs / 9.5kg Length: 6.6" / 168mm Width: 5.2" / 132mm Height: 6.8" / 173mm Polarity: Right Side Positive Terminal Type: Steel terminal block with M6 bolt Performance Specifications: Voltage: 12v Recharge Voltage: 14.4V – 14.6V Maintenance charge voltage: 13.8V 5s Pulse Cranking Amps (PCA): 1380 10s PDC: 124 Amp Hour (Ah): 31 Watt Hour (Wh): 372 Life Cycle @ 10% DOD: 3100 Charging Temperature 0C to 50C Discharge Temperature range -40C to +60C Storage temperature -40C to +60C *THIS BATTERY REQUIRES A CUSTOM MOUNTING SOLUTION. The size and weight are significantly smaller than a stock battery and will not be held in place by the stock battery mount*
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Braille Performance Intensity Carbon Lithium-ION Battery - i48CX - 10.5lbs
Braille Performance Intensity Carbon Lithium-ION Battery - i48CX - 10...
This item is classified as Hazardous Materials and requires special shipping and handling. We cannot ship this item out of the US or with priority shi
Braille - Corporate Logo
T#:558047
Part#: I48CX
Ships in 5 Business Days
$ 1,164.99 USD
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$ 1,164.99 USD
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The ultra-lightweight, standard height I48CX lithium-ION battery from Braille Battery is a popular choice among BMW enthusiasts looking for a drop-in replacement battery that shaves off a ton of weight, 35 pounds in total! Thanks to the Group 48 design of this battery, no modifications are needed for installation. This is perfect for anyone looking to drive their car both on and off of the track, without any negative side effects, and wants a battery with a 10-15 year life span!
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Hella Hella Horn - High Tone
Hella Hella Horn - High Tone
Hella - Corporate Logo
T#:592707
Part#: 2768551
In Stock
$ 30.99 USD
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$ 30.99 USD
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Disc Type High-Tone, 12 V, 400 Hz with Bracket
Hella Hella Horn - Low Tone
Hella Hella Horn - Low Tone
Hella - Corporate Logo
T#:590880
Part#: 2768082
In Stock
$ 36.99 USD
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$ 36.99 USD
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Disc Type Low-Tone, 12 V, 335 Hz with Bracket
Braille Performance GreenLite Lithium-ION Battery - G30 - 5.5lbs
Braille Performance GreenLite Lithium-ION Battery - G30 - 5.5lbs ...
Braille - Corporate Logo
T#:558046
Part#: G30
Ships in 6 Business Days
$ 522.99 USD
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$ 522.99 USD
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The G30 lithium battery from Braille is designed for the Import Tuner market (4 and 6 cylinder) for track use and has enough power for small black V8 race cars and hot rods with light electrical demands/accessories and standard compression. The G30 comes in the popular ETX 30 Group size, just like the B3121 AGM, so it is small and light enough to mount in a variety of locations. Incorporated in this battery is the same technology used in their race winning batteries used by nearly every OEM developer in classes ranging from SCCA to Formula 1.
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Hella Air Horn Kit
Hella Air Horn Kit
Hella - Corporate Logo
T#:592708
Part#: 3001651
Ships in 1 Business Day
$ 143.99

This product was last offered at the strikethrough price on
05-07-2026

$ 124.99 USD
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$ 124.99 USD
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Get noticed with this air horn kit from Hella!
Hella Horn - Low-Tone
Hella Horn - Low-Tone
Hella - Corporate Logo
T#:28869559
Part#: 7424001
Ships in 4 Business Days
$ 17.99 USD
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$ 17.99 USD
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Universal fit. Not direct fit.
Hella Horn - High-Tone
Hella Horn - High-Tone
Hella - Corporate Logo
T#:592716
Part#: 7424011
In Stock
$ 17.99 USD
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$ 17.99 USD
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Upgrade the sound of your BMW or MINI with the Hella Horn - High-Tone. This high-quality horn delivers a powerful and attention-grabbing sound, enhancing safety on the road. Designed for easy installation, it provides a quick and effective way to improve the audible presence of your vehicle.

  • Powerful and attention-grabbing sound
  • Enhances safety on the road
  • Easy installation for convenience
  • Compatible with BMW and MINI models
  • High-quality construction for durability

Enhance the audible presence of your BMW or MINI with the Hella Horn - High-Tone, ensuring you're heard when it matters most.

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Hella Relay
Hella Relay
Hella - Corporate Logo
T#:592718
Part#: 965400001
In Stock
$ 14.99 USD
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$ 14.99 USD
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12V 30A SPST relay with bracket
Morimoto Standalone Can-Bus Wiring Harness - H4 / 9003 - Priced Each
Morimoto Standalone Can-Bus Wiring Harness - H4 / 9003 - Priced Each ...
Morimoto - Corporate Logo
T#:54388428
Part#: H240
Ships in 4 Business Days
New Item
$ 21.99 USD
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$ 21.99 USD
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