BMW Electrical Sensors, Switches, & Relays for BMW 3 Series E46 (1999-2005)

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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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Hitachi - Corporate Logo
T#:48850072
Part#: 12147539165
In Stock
$ 41.99 USD
Free Shipping on orders $49 and up
$ 41.99 USD
Free Shipping on orders $49 and up
A bad cam sensor can cause a variety of problems from hard starting to stalling at low speeds. Cam sensor replacement has been known to cure many drivabilty issues. Uses O-ring # 12 141 748 398 (not included)
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LK-2M 2 Pin Connector Package
10X Entries Into Our F80 M3 Sweepstakes 10X Entries For Our Spin To Win Sweepstakes!
ECS - Corporate Logo
T#:40072446
Part#: LK2M
In Stock
Sale - Save 34% $ 6.99

This product was last offered at the strikethrough price on
11-07-2026

$ 4.61 USD
Free Shipping on orders $49 and up
Sale - Save 34%
$ 6.99

This product was last offered at the strikethrough price on
11-07-2026

$ 4.61 USD
Free Shipping on orders $49 and up

Includes connector housing with terminals and seals. Commonly used for the engine oil pressure switch.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943

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Oil Pressure Switch (fits most BMWs)
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:363
Part#: 12617568480
In Stock
$ 7.99

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

$ 5.39 USD
Free Shipping on orders $49 and up
$ 5.39 USD
Free Shipping on orders $49 and up
Having your oil pressure light come on can mean very serious problems. Or it could just be this switch that fails several times over a car's lifespan. By no means should you ignore the warning light but replacing this sensor could be the actual culprit. The other problem with this switch is that oil can leak past its seal. With the oil under a lot of pressure at this point, the oil loss can be a serious concern. It's a simple replacement when doing most oil change work.

This Oil Pressure Switch fits the following BMWs:
1985-1991 E30 318i, 318is, 325e, 325i, M3
1992-1999 E36 318i/is, 325i/is, 328i/is, 323is, M3
1992-1997 E31 840i, 850i
1988-1994 E32 735i, 735iL, 740i, 740iL
1989-1995 E34 525i, 530i, 535i, 540i, M5
1995-2001 E38 740i, 740iL, 750i, 750iL
1996-2002 Z3 Roadster/Coupe 1.9, 2.3, 2.5, 2.8, 3.0, 3.2
1997-2003 E39 525i, 528i, 530i, 540i, M5
1999-2005 E46 323, 325, 328, 330, M3
2000-2003 Z8 roadster
2001-2006 E53 X5 X5 3.0i, X5 4.4i, X5 4.6is, X5 4.8is
2002+ E65/E66 745i, 745li, 750i, 750li, 760i, B7 Alpina
2003+ Z4 Roadster/Coupe Z4 2.5, 3.0, 3.0si
2004+ E60 525i, 530i, 535i, 545i, 550i, M5
2005+ E63/E64 645Ci, 650i, M6
2005+ E83 X3 X3 2.5, X3 3.0
2006+ E90/E92 325, 328, 330, 335
2007+ E70 X5 X5 3.0i, X5 4.8i
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3 Pin Connector
10X Entries Into Our F80 M3 Sweepstakes 10X Entries For Our Spin To Win Sweepstakes!
ECS - Corporate Logo
T#:33412931
Part#: 12527519996
In Stock
Sale - Save 40% $ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up
Sale - Save 40%
$ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up

Includes connector housing with terminals and seals. Commonly used for the pencil-style ignition coil connector.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

*OEM cross reference PN# 12527519996 - Commonly used for the pencil-style ignition coil connector.

Please reference the original part number from the existing connector to confirm fitment, before ordering.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943

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3 Pin Connector
10X Entries Into Our F80 M3 Sweepstakes 10X Entries For Our Spin To Win Sweepstakes!
ECS - Corporate Logo
T#:33412918
Part#: 12521732596
In Stock
Sale - Save 40% $ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up
Sale - Save 40%
$ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up

Includes connector housing with terminals and seals. Commonly used for the camshaft position sensor.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

*OEM cross reference PN# 12521732596 - Commonly used for the camshaft position sensor.

Please reference the original part number from the existing connector to confirm fitment, before ordering.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943

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3 Pin Connector
10X Entries Into Our F80 M3 Sweepstakes 10X Entries For Our Spin To Win Sweepstakes!
ECS - Corporate Logo
T#:33412947
Part#: 12521433916
In Stock
Sale - Save 40% $ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up
Sale - Save 40%
$ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up

Includes connector housing with terminals and seals. Commonly used for the crankshaft position sensor.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

*OEM cross reference PN# 12521433916 - Commonly used for the crankshaft position sensor.

Please reference the original part number from the existing connector to confirm fitment, before ordering.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943

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3 Pin Connector
10X Entries Into Our F80 M3 Sweepstakes 10X Entries For Our Spin To Win Sweepstakes!
ECS - Corporate Logo
T#:33412924
Part#: 12521433917
Ships on Jan 27, 2027
Sale - Save 14% $ 8.99

This product was last offered at the strikethrough price on
10-28-2026

$ 7.69 USD
Free Shipping on orders $49 and up
Sale - Save 14%
$ 8.99

This product was last offered at the strikethrough price on
10-28-2026

$ 7.69 USD
Free Shipping on orders $49 and up

Includes connector housing with terminals and seals. Commonly used for the camshaft position sensor.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

*OEM cross reference PN# 12521433917 - Commonly used for the camshaft position sensor.

Please reference the original part number from the existing connector to confirm fitment, before ordering.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943

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3 Pin Connector
10X Entries Into Our F80 M3 Sweepstakes 10X Entries For Our Spin To Win Sweepstakes!
ECS - Corporate Logo
T#:33412925
Part#: 12521433915
In Stock
Sale - Save 40% $ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up
Sale - Save 40%
$ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up

Includes connector housing with terminals and seals. Commonly used for the engine oil level sensor.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

*OEM cross reference PN# 12521433915 - Commonly used for the engine oil level sensor.

Please reference the original part number from the existing connector to confirm fitment, before ordering.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943

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Liqui-Moly Battery Clamp Grease - 50 grams
10X Entries Into Our F80 M3 Sweepstakes 10X Entries For Our Spin To Win Sweepstakes!
We Price Match - Give Us A Call or Chat!
Liqui-Moly - Corporate Logo
T#:1195997
Part#: 20244
In Stock
30% off MSRP $ 7.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 5.59 USD
Free Shipping on orders $49 and up
30% off MSRP
$ 7.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 5.59 USD
Free Shipping on orders $49 and up
Excellent corrosion protection for your battery and other connections

Hitachi - Corporate Logo
T#:48850055
Part#: 12147518628
Ships in 2 Business Days
$ 71.99 USD
Free Shipping on orders $49 and up
The camshaft position sensor is essential for assisting the engine DME by monitoring the camshaft's position. The data from this sensor is key to optimizing ignition timing and ensuring smooth engine performance. Often referred to as the CMP sensor, this component is crucial for the overall functionality of the powertrain. A failing camshaft position sensor can cause a range of issues, including engine stumbling, hesitation during acceleration, power loss, and even starting difficulties or complete failure to start.
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SEG Automotive - Corporate Logo
T#:54851984
Part#: 12317541694
Ships in 1 Business Day
New Item
$ 521.99

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

$ 470.99 USD
Free Shipping on orders $49 and up
$ 470.99 USD
Free Shipping on orders $49 and up
SEG Automotive - Corporate Logo
T#:54851980
Part#: 12317519618
Ships on Dec 7, 2026
New Item
$ 503.99

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

$ 500.99 USD
Free Shipping on orders $49 and up
$ 500.99 USD
Free Shipping on orders $49 and up


SEG Automotive - Corporate Logo
T#:58965212
Part#: 0124.525.561
Ships on Dec 7, 2026
New Item
$ 487.99 USD
Free Shipping on orders $49 and up
SEG Automotive, the company behind Bosch's starter motor and generator business, builds this brand-new 150-amp alternator with a freewheel pulley that smooths out belt loads for a quieter, longer-lasting accessory drive.
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SEG Automotive - Corporate Logo
T#:58965210
Part#: 0124.515.052
Ships on Dec 7, 2026
New Item
$ 485.99 USD
Free Shipping on orders $49 and up
A strong charging system keeps everything from your ignition to your stereo working at its best, and a failing alternator can undermine all of it.
SEG Automotive - Corporate Logo
T#:58965213
Part#: 0124.525.523
Ships on Dec 7, 2026
New Item
$ 495.99 USD
Free Shipping on orders $49 and up
Your BMW's charging system powers everything from ignition to infotainment, so a weak alternator affects the whole car.

2 Pin Connector
10X Entries Into Our F80 M3 Sweepstakes 10X Entries For Our Spin To Win Sweepstakes!
ECS - Corporate Logo
T#:33412928
Part#: 12521427615
In Stock
Sale - Save 35% $ 7.99

This product was last offered at the strikethrough price on
11-07-2026

$ 5.19 USD
Free Shipping on orders $49 and up
Sale - Save 35%
$ 7.99

This product was last offered at the strikethrough price on
11-07-2026

$ 5.19 USD
Free Shipping on orders $49 and up
Includes connector housing with terminals and seals. Commonly used for the engine oil pressure switch. ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need. Each connector includes an additional terminal in case one becomes lost or damaged during installation. *OEM cross reference PN# 12521427615 - Commonly used for the engine oil pressure switch. Please reference the original part number from the existing connector to confirm fitment, before ordering. Suggested tools: Suggested crimping pliers: T#387193 Wire De-pin tools: 12pc De-Pin Tool Set - T#386379 23pc De-Pin Tool Set - T#641943
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2 Pin Connector
10X Entries Into Our F80 M3 Sweepstakes 10X Entries For Our Spin To Win Sweepstakes!
ECS - Corporate Logo
T#:33412932
Part#: 61132359999
In Stock
Sale - Save 40% $ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up
Sale - Save 40%
$ 10.99

This product was last offered at the strikethrough price on
11-07-2026

$ 6.59 USD
Free Shipping on orders $49 and up

Includes connector housing with terminals and seals. Commonly used for the coolant level sensor.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

*OEM cross reference PN# 61132359999 - Commonly used for the coolant level sensor.

Please reference the original part number from the existing connector to confirm fitment, before ordering.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943

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Hitachi - Corporate Logo
T#:48815470
Part#: 12141709616
Back Ordered
$ 32.99 USD
Free Shipping on orders $49 and up
NOTE: Does not include o-ring seal - see BMW # 12141748398 This is the crankshaft position sensor. It provides information for the ECU. A faulty sensor can cause issues with timing adjustment and limit performance and vehicle operation. Replace your sensor with a high-quality Hitachi sensor to restore peak performance.
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