Find Parts That Fit Your Vehicle

BMW Electrical Sensors, Switches, & Relays

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.

Sub-Categories

Sort By:

ECS - Corporate Logo
T#:49996974
Part#: 059235LA01
In Stock
New Item
Sale - Save 20% $ 29.99

This product was last offered at the strikethrough price on
06-14-2026

$ 23.99 USD
Free Shipping
Sale - Save 20%
$ 29.99

This product was last offered at the strikethrough price on
06-14-2026

$ 23.99 USD
Free Shipping

If you're experiencing hard starting, flaky charging, or other electrical issues, your engine ground strap may be the culprit. On older BMWs, the engine ground strap is a thin, non-insulated cable that spans from the engine mount arm to the frame horn. Despite the seemingly simple nature of this part, on older cars, it is known to cause massive headaches. Due to its non-insulated design, years of exposure to water, dirt, and road salt will cause the wire to corrode, ultimately leading to complete failure. A break in this cable will cause an open circuit, resulting in issues with the vehicle's electrical system and potentially leading to a no-start condition.

To solve this issue, ECS has engineered an exact-fit, upgraded ground strap for your BMW! Unlike its OEM counterpart, this design features insulated, large-gauge copper wire for dependable conductivity and long-lasting durability. Additionally, factory-style lugs are zinc-coated, crimped, and soldered, ensuring protection against corrosion and oxidation.

Whether you're replacing a visibly corroded strap or proactively preventing failure, this solution from ECS is sure to provide lasting performance and protection.

FEATURES

Direct-fit replacement and upgrade for E30 (318i/is), E36, E39, E46, and others Solves intermittent grounding issues caused by aging OEM straps Clean, stealthy design that fits seamlessly in factory engine bays Factory length and lug orientation for drop-in fitment 2 AWG tinned copper cable for excellent conductivity and corrosion resistance Zinc-coated lugs, crimped and soldered to resist moisture and oxidation Black UL1015-grade insulation withstands oil, heat, and abrasion Discreet ECS label for a clean, OEM+ look Replaces OEM part numbers 12421737755 and 12421714262.

Show More Show Less
ECS - Corporate Logo
T#:49996976
Part#: 059261LA01
In Stock
New Item
Sale - Save 25% $ 29.99

This product was last offered at the strikethrough price on
06-14-2026

$ 22.49 USD
Free Shipping
Sale - Save 25%
$ 29.99

This product was last offered at the strikethrough price on
06-14-2026

$ 22.49 USD
Free Shipping

If you're experiencing hard starting, flaky charging, or other electrical issues, your engine ground strap may be the culprit. On E70/E71 BMWs, the engine ground strap is a thin, non-insulated cable that spans from the left engine mount arm to the frame horn. Despite the seemingly simple nature of this part, on older cars, it is known to cause massive headaches. Due to its non-insulated design, years of exposure to water, dirt, and road salt will cause the wire to corrode, ultimately leading to complete failure. A break in this cable will cause an open circuit, resulting in issues with the vehicle's electrical system and potentially leading to a no-start condition.

To solve this issue, ECS has engineered an exact-fit, upgraded ground strap for your BMW X5/X6! Unlike its OEM counterpart, this design features insulated, large-gauge copper wire for dependable conductivity and long-lasting durability. Additionally, factory-style lugs are zinc-coated, crimped, and soldered, ensuring protection against corrosion and oxidation.

Whether you're replacing a visibly corroded strap or proactively preventing failure, this solution from ECS is sure to provide lasting performance and protection.

FEATURES

Direct-fit replacement and upgrade for E70 X5 and E71 X6 applications Solves intermittent grounding issues caused by aging OEM straps Clean, stealthy design that fits seamlessly in factory engine bays Factory length and lug orientation for drop-in fitment 2 AWG tinned copper cable for excellent conductivity and corrosion resistance Zinc-coated lugs, crimped and soldered to resist moisture and oxidation Black UL1015-grade insulation withstands oil, heat, and abrasion Discreet ECS label for a clean, OEM+ look Replaces OEM part number 12427557027.

Show More Show Less
Bosch - Corporate Logo
T#:54388475
Part#: 13627636937
In Stock
New Item
$ 29.99 USD
Free Shipping on orders $49 and up
Keep your ignition timing razor-sharp and your engine safe from destructive detonation. This replacement Knock Sensor acts as your engine's first line of defense, constantly listening for pre-ignition "pinging" or knocking.
Show More Show Less

Braille - Corporate Logo
T#:54388454
Part#: I34RX
Ships in 6 Business Days
New Item
$ 949.99 USD
Free Shipping on orders $49 and up
Whether you're building a dedicated track weapon or upgrading your street machine for ultimate reliability, unsprung and upper-chassis weight is the enemy of performance. Positioned high up in the engine bay or rear corners, a heavy factory battery negatively impacts your car's center of gravity.
Show More Show Less

SEG Automotive - Corporate Logo
T#:54851991
Part#: 12317560985
Ships in 2 Business Days
New Item
$ 1,049.99

This product was last offered at the strikethrough price on
07-16-2026

$ 949.99 USD
Free Shipping on orders $49 and up
$ 949.99 USD
Free Shipping on orders $49 and up
Vargas Turbo Technologies - Corporate Logo
T#:51778112
Part#: N54-USB-SERIAL-H
Ships in 10 Business Days
New Item
$ 37.99 USD
Free Shipping
$ 37.99 USD
Free Shipping
Take full control of your N54’s fueling system with the Vargas Turbo Technologies USB to Serial adapter.

SEG Automotive - Corporate Logo
T#:54851993
Part#: 12317613445
Ships in 2 Business Days
New Item
$ 564.99

This product was last offered at the strikethrough price on
07-16-2026

$ 510.99 USD
Free Shipping on orders $49 and up
$ 510.99 USD
Free Shipping on orders $49 and up
Vargas Turbo Technologies - Corporate Logo
T#:51672717
Part#: VTT-MAP-HARNESS
Ships in 10 Business Days
New Item
$ 59.99 USD
Free Shipping
$ 59.99 USD
Free Shipping
As part of the VTT-FAB fabrication line, this extension harness is designed for builders and tuners who need flexibility.

SEG Automotive - Corporate Logo
T#:54851988
Part#: 12317550319
Ships in 2 Business Days
New Item
$ 473.99

This product was last offered at the strikethrough price on
07-16-2026

$ 430.99 USD
Free Shipping on orders $49 and up
$ 430.99 USD
Free Shipping on orders $49 and up

SEG Automotive - Corporate Logo
T#:54851984
Part#: 12317541694
Ships in 2 Business Days
New Item
$ 521.99

This product was last offered at the strikethrough price on
07-16-2026

$ 468.99 USD
Free Shipping on orders $49 and up
$ 468.99 USD
Free Shipping on orders $49 and up
Vargas Turbo Technologies - Corporate Logo
T#:51813310
Part#: VTT-FAB-HC
Ships in 10 Business Days
New Item
$ 49.99 USD
Free Shipping
$ 49.99 USD
Free Shipping
Simplify your next fabrication project with the VTT-FAB series Coolant Extension Harness.
Vargas Turbo Technologies - Corporate Logo
T#:52129729
Part#: VTT56BSENSKIT64
Ships in 10 Business Days
New Item
$ 209.99 USD
Free Shipping
$ 209.99 USD
Free Shipping
The VTT 6-Bar MAP sensor kit provides the necessary overhead to monitor boost levels with a linear voltage scale that makes software calibration straightforward.


SEG Automotive - Corporate Logo
T#:55857741
Part#: 12417610344
Ships in 2 Business Days
New Item
$ 368.99

This product was last offered at the strikethrough price on
07-16-2026

$ 330.99 USD
Free Shipping on orders $49 and up
$ 330.99 USD
Free Shipping on orders $49 and up
SEG Automotive - Corporate Logo
T#:54851980
Part#: 12317519618
Ships in 2 Business Days
New Item
$ 503.99

This product was last offered at the strikethrough price on
07-16-2026

$ 453.99 USD
Free Shipping on orders $49 and up
$ 453.99 USD
Free Shipping on orders $49 and up
Bosch - Corporate Logo
T#:57231530
Part#: 12411427080
Special Order: No Guaranteed ETA
New Item
$ 78.99 USD
Free Shipping on orders $49 and up
When you are at the track or gearing up for a weekend backroad drive, the last thing you need is a sluggish starter holding your BMW back.

Bosch - Corporate Logo
T#:57267768
Part#: 12317616126
Special Order: No Guaranteed ETA
New Item
$ 571.99 USD
Free Shipping on orders $49 and up
Keep your BMW's vital electronics powered and your engine running at peak efficiency with a premium remanufactured alternator from Bosch.

Bosch - Corporate Logo
T#:57304035
Part#: SR3295N
Special Order: No Guaranteed ETA
New Item
$ 441.99 USD
Free Shipping on orders $49 and up
This new starter delivers crisp power and rapid engine speed recovery, avoiding the typical voltage drop issues associated with worn original units.
Bosch - Corporate Logo
T#:57267766
Part#: 12317605478
Special Order: No Guaranteed ETA
New Item
$ 499.99 USD
Free Shipping on orders $49 and up
Maintain peak battery performance and protect your vehicle's complex electrical architecture with a motorsport-tested, factory-grade charging replacement.

Bosch - Corporate Logo
T#:57231540
Part#: 12311466084
Special Order: No Guaranteed ETA
New Item
$ 286.99 USD
Free Shipping on orders $49 and up
Ensure your BMW or European vehicle maintains uninterrupted power under demanding driving conditions with this premium remanufactured alternator by Bosch.
Bosch - Corporate Logo
T#:57267807
Part#: 12418621839
Special Order: No Guaranteed ETA
New Item
$ 342.99 USD
Free Shipping on orders $49 and up

Bosch - Corporate Logo
T#:57267763
Part#: AL0757X
Special Order: No Guaranteed ETA
New Item
$ 430.99 USD
Free Shipping on orders $49 and up
This high-output Bosch remanufactured alternator ensures your ignition system and performance electronics receive clean, steady amperage under high-demand driving conditions.

Bosch - Corporate Logo
T#:57267806
Part#: 12418625995
Special Order: No Guaranteed ETA
New Item
$ 463.99 USD
Free Shipping on orders $49 and up
Bosch starter units deliver the high-torque cranking performance required to reliably start modern high-compression BMW engines under all thermal conditions.
Bosch - Corporate Logo
T#:57304037
Part#: 12417843530
Special Order: No Guaranteed ETA
New Item
$ 412.99 USD
Free Shipping on orders $49 and up
Ensure your high-performance engine cranks reliably every time with an OE-quality starter motor from Bosch.
Bosch - Corporate Logo
T#:57267767
Part#: 12317561004
Special Order: No Guaranteed ETA
New Item
$ 695.99 USD
Free Shipping on orders $49 and up
This Bosch remanufactured alternator delivers the rock-solid current required to keep your ignition, fuel management, and chassis electronics operating at peak efficiency under demanding conditions.