BMW Electrical Sensors, Switches, & Relays

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.

If you're experiencing hard starting, flaky charging, or other electrical issues, your engine ground strap may be the culprit. On E9X 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 E9X 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 RWD E82/E88, E84, and E9X 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 numbers 12427549393, 12427795404, and 12427790559.

If your car won't turn over, there is a good chance your starter is shot. Bosch's OEM starter is a high quality replacement that will give you peace of mind thanks to its long life-span. OEM replacement for BMW part # 12412354693, 12412344242, 12412167996.

Bosch is one of the largest OEM producers of Genuine BMW and aftermarket parts in the world, providing parts for almost every major automotive manufacturer. Bosch has likely supplied many of the original electrical (and mechanical) parts for your BMW. Thanks to their quality, high durability, and reliability, you should expect a long service life from Bosch products.

As a leading source of high performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts.  All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

For BMW's with the M54 engine with a production date from 09/2002.

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.

A replacement Bosch alternator for the 2001-2006 M3. Bosch is an original equipment supplier to BMW, and is the finest and most recognized German brand of alternator available. The Original BMW alternator sells for over double! Buy only the best alternator for your BMW -- buy a Bosch alternator. This is an OEM replacement for BMW part # 12317831436.

Bosch is one of the largest OEM producers of Genuine BMW and aftermarket parts in the world, providing parts for almost every major automotive manufacturer. Bosch has likely supplied many of the original electrical (and mechanical) parts for your BMW. Thanks to their quality, high durability, and reliability, you should expect a long service life from Bosch products.

As a leading source of high performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts.  All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

A $80.00 refundable core charge must be applied to this alternator. Upon receipt of your rebuildable alternator core, you will be refunded the core charge. 

This item fits the following BMWs:
2001-2006 E46 BMW M3, M3 Convertible
2001-2002 Z3 BMW M Roadster M Coupe

If your car has died on the side of the road from a dead battery and you notice flickering or low powered headlights, it's likely your alternator failing. To be sure you are getting a high-quality part with a long life-span, choose this OEM Bosch Alternator. This is a brand new OEM replacement for BMW part # 12317501690.

Bosch is one of the largest OEM producers of Genuine BMW and aftermarket parts in the world, providing parts for almost every major automotive manufacturer. Bosch has likely supplied many of the original electrical (and mechanical) parts for your BMW. Thanks to their quality, high durability, and reliability, you should expect a long service life from Bosch products.

As a leading source of high-performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts. All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

Knock sensors detect pings in the engine and adjust ignition timing to restore perfect operation. Faulty knock sensors will throw engine codes or even lead to engine damage. Replace your sensor with a reliable, high quality Bosch sensor to ensure proper engine ignition timing.

Bosch # 13627568421 OEM replacement for BMW part # 13627568421, 12141709317, and 12141435502.

Bosch is one of the largest OEM producers of Genuine BMW and aftermarket parts in the world, providing parts for almost every major automotive manufacturer. Bosch has likely supplied many of the original electrical (and mechanical) parts for your BMW. Thanks to their quality, high durability, and reliability, you should expect a long service life from Bosch products.

As a leading source of high performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts.  All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

If your car has died on the side of the road from a dead battery and you notice flickering or low powered head lights, it's likely your alternator failing. To be sure you are getting a high quality part with a long life-span, choose this OEM Bosch Alternator. This is an OEM replacement for BMW part # 12311407440.

Bosch is one of the largest OEM producers of Genuine BMW and aftermarket parts in the world, providing parts for almost every major automotive manufacturer. Bosch has likely supplied many of the original electrical (and mechanical) parts for your BMW. Thanks to their quality, high durability, and reliability, you should expect a long service life from Bosch products.

As a leading source of high performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts.  All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

A refundable $70.00 core charge must be applied to this alternator. Upon receipt of your rebuildable alternator core, you will be refunded the core charge.

This item fits the following BMWs: 
1999-2003 E39 BMW M5 
 

If your headlights or interior are flickering or dimming while driving, there is a good chance your alternator is dying. This high quality Bosch replacement will have your electrical system back in top shape. OEM replacement for 12311744567 and 12311738352.

Bosch is one of the largest OEM producers of Genuine BMW and aftermarket parts in the world, providing parts for almost every major automotive manufacturer. Bosch has likely supplied many of the original electrical (and mechanical) parts for your BMW. Thanks to their quality, high durability, and reliability, you should expect a long service life from Bosch products.

As a leading source of high performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts.  All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

A $80.00 refundable core charge is applied to this alternator. Upon receipt of your rebuildable alternator core, you will be refunded the core charge. 

Bosch is one of the largest OEM producers of Genuine BMW and aftermarket parts in the world, providing parts for almost every major automotive manufacturer. Bosch has likely supplied many of the original electrical (and mechanical) parts for your BMW. Thanks to their exacting assembly process and high level of durability you can expect a long service life from all Bosch products.​

This genuine Bosch Starter fits the following BMWs:
1984-1985 E30 3 Series 323i 325e 325es
1982-12/1986 E28 5 Series 528e
1977-1983E21 3 Series 320/6 323i

Includes $45.00 core charge to be refunded on return of your rebuildable core.

Ensure optimal engine performance in your Mini with this Bosch oxygen sensor. Designed to replace a malfunctioning sensor, this unit measures the amount of unburned fuel in the exhaust pipe, allowing for adjustments to fuel mapping for reduced emissions and improved fuel economy.

• Restores engine performance and mileage
• Easy installation for quick restoration of vehicle performance
• Prevents sensor seizing with anti-seize application
• Regular maintenance helps prevent gradual sensor failure
• OEM supplier Bosch ensures quality and compatibility with Mini vehicles

Upgrade your Mini's engine efficiency and reduce emissions with this high-quality Bosch oxygen sensor.

Bosch is one of the largest OEM producers of Genuine BMW and aftermarket parts in the world, providing parts for almost every major automotive manufacturer. Bosch has likely supplied many of the original electrical (and mechanical) parts for your BMW. Thanks to their exacting assembly process and high level of durability you can expect a long service life from all Bosch products.

This genuine Bosch Starter motor fits the following BMWs:
1992-1994 E32 7 Series 740i, 740il
1993-1995 E34 5 Series 530i, 530i wagon, 540i
1995-2001 E38 7 Series 740i, 740il
1997-2003 E39 5 Series 540i M5
2000-2003 E53 X5 X5 4.4i X5 4.6is - M62 engine
2000-2003 Z8 Z8

Includes $100.00 core charge to be refunded on return of your rebuildable core.

Replacement 150 amp water cooled Bosch alternator for 1999-2001 E38 740i & 740iL, 1999-2003 E39 540i, and 2000-2003 X5 V8 (4.4 and 4.6 liter). Bosch is an original equipment supplier to BMW, and is the finest and most recognized German brand of alternator available. Buy only the best alternator for your BMW -- buy a Bosch alternator. Replaces part number 12317508054

Bosch is one of the largest OEM producers of Genuine BMW and aftermarket parts in the world, providing parts for almost every major automotive manufacturer. Bosch has likely supplied many of the original electrical (and mechanical) parts for your BMW. Thanks to their exacting assembly process and high level of durability you can expect a long service life from all Bosch products.

A refundable core charge must be applied to this alternator. Upon receipt of your rebuildable alternator core, you will be refunded the core charge.

This Bosch Alternator fits the following BMWs:
1999-2001 E38 7 Series 740i & 740iL
1999-2003 E39 5 Series 540i sedan & 540i touring wagon
2000-2003 X5 SAV with V8 engine - X5 4.4 & X5 4.6is

Includes $100.00 core charge to be refunded on return of your rebuildable core.