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  • OEM Valeo Voltage Regulator M646
OEM Alternator Voltage Regulator M646, aftermarket replacement, starter parts, alternator parts, automotive electrical
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OEM Valeo Voltage Regulator M646

Valeo
M646OEM
In stock
Voltage Regulator
$80.00
OEM Valeo Voltage Regulator M646

Shipping

In-stock orders ship out same day or next business day via USPS.

Pre Order

Pre-orders ship out in the order received within 7–21 business days.

Customer Support

Need help finding a part? Contact Support@RCAutoElectric.com

Description

Specifications

  • MFR: VALEO
  • FEATURE 1:100% New OEM
  • FEATURE 2:BSS (COM) Regulator
  • FEATURE 3:COM ID Code: 56
  • FEATURE 4:BSS Terminal Function
  • FEATURE 5:Field Rating 5 Amps
  • FEATURE 6:Voltage Set point and Regulation Mode is controlled by Vehicle
  • FEATURE 7:With Field Short Circuit Protection
  • FEATURE 8:Stator Activated
  • SPECS FOR:Valeo IR/IF Alternators
  • SPECS:12 Volt, B-Circuit, High Side Drive Regulator, COM-NC Terminals, 14.4 Vset

USED ON

  • Mercedes-Benz (2003-2005)

Replaces

  • BMW 7536660, Original Reference Number IA4642OE, Valeo 593780, 593873, 593986

LESTER NUMBERS

  • 11066, 11312, 23347, 24116

UNIT NUMBERS

  • BMW 12-31-7-521-135, 12-31-7-521-136, 12-31-7-521-137, 12-31-7-521-138, 12-31-7-800-308, 12-31-7-802-928, 12-31-7-836-610, 12-31-7-837-691; Mercedes-Benz 271-154-09-02, A271-154-09-02; Original Reference Number 2586077; Valeo 2542582B, SG12B062, TG15C018, TG15C018B, TG15C072, TG15C098

Vehicle Application

Mercedes-Benz Car
C230 L4 1.8L 1796cc 2003-2005
CL200 L4 1.8L 1796cc 110cid 2003
CL230 L4 2.3L 2295cc 2002-2005
SLK200 L4 1.8L 1796cc 110cid 2007-2009

BMW Car
325Ci L6 2.5L 2494cc 152cid 2004-2006
325i L6 2.5L 2494cc 152cid 2004-2005
325xi L6 2.5L 2494cc 152cid 2004-2005
330Ci L6 3.0L 2979cc 2004-2005
330i L6 3.0L 2979cc 2004-2005
330xi L6 3.0L 2979cc 2004-2005
Z4 L6 3.2L 3246cc 2006-2008

BMW - Europe Car
3 (E90) Eng.M57 D30 (306D5) 335 d 210kW M57 D30 (306D5) 2006-2011
3 Coupe (E92) Eng.M57 D30 (306D5) 335 d 210kW M57 D30 (306D5) 2006-2013
3 Touring (E91) Eng.M57 D30 (306D5) 335 d 210kW M57 D30 (306D5) 2006-2012
330d N57D30A, 2993cc, 3.0 2008-2011
330d xDrive N57D30A, 2993cc, 3.0 2008-2011
5 (E60) Eng.M54 B22 (226S1) 520 i 125kW M54 B22 (226S1) 2003-2005
5 (E60) Eng.M54 B25 (256S5) 525 i 141kW M54 B25 (256S5) 2003-2010
5 (E60) Eng.M54 B30 (306S3) 530 i 170kW M54 B30 (306S3) 2003-2005
5 (E60) Eng.M47 D20 (204D4) 520 d 110kW M47 D20 (204D4) 2005-2008
5 (E60) Eng.M47 D20 (204D4), N47 D20 A, N47 D20 C 520 d 120kW M47 D20 (204D4), N47 D20 A, N47 D20 C 2005-2008
5 (E60) Eng.M57 306 D3 530 d 170kW M57 306 D3 2005-2007
5 (E60) Eng.M57 306 D3 530 xd 170kW M57 306 D3 2005-2007
5 (E60) Eng.M57 D25 (256D1) 525 d 120kW M57 D25 (256D1) 2004-2010
5 (E60) Eng.M57 D25 TU, M57N 256 D4 525 d 130kW M57 D25 TU, M57N 256 D4 2004-2010
5 (E60) Eng.M57 D30 (306D2) 530 d 160kW M57 D30 (306D2) 2002-2005
5 (E60) Eng.M57 D30 (306D2), M57 D30 (306D3) 530 d 155kW M57 D30 (306D2), M57 D30 (306D3) 2002-2009
5 (E60) Eng.M57 D30 (306D3) 525 d 145kW M57 D30 (306D3) 2007-2010
5 (E60) Eng.M57 D30 (306D3) 525 d xDrive 145kW M57 D30 (306D3) 2007-2009
5 (E60) Eng.M57 D30 (306D3) 525 xd 145kW M57 D30 (306D3) 2006-2007
5 (E60) Eng.M57 D30 (306D3) 530 d 173kW M57 D30 (306D3) 2006-2009
5 (E60) Eng.M57 D30 (306D3) 530 d xDrive 173kW M57 D30 (306D3) 2007-2009
5 (E60) Eng.M57 D30 (306D3) 530 xd 173kW M57 D30 (306D3) 2006-2007
5 (E60) Eng.M57 D30 (306D4) 535 d 200kW M57 D30 (306D4) 2004-2010
5 (E60) Eng.M57 D30 (306D5) 535 d 210kW M57 D30 (306D5) 2007-2010
5 Touring (E61) Eng.M54 B25 (256S5) 525 i 141kW M54 B25 (256S5) 2004-2010
5 Touring (E61) Eng.M47 D20 (204D4), N47 D20 A, N47 D20 C 520 d 110kW M47 D20 (204D4), N47 D20 A, N47 D20 C 2005-2008
5 Touring (E61) Eng.M47 D20 (204D4), N47 D20 A, N47 D20 C 520 d 120kW M47 D20 (204D4), N47 D20 A, N47 D20 C 2005-2008
5 Touring (E61) Eng.M57 306 D3 530 d 170kW M57 306 D3 2005-2010
5 Touring (E61) Eng.M57 306 D3 530 xd 170kW M57 306 D3 2005-2010
5 Touring (E61) Eng.M57 D25 TU, M57N 256 D4 525 d 130kW M57 D25 TU, M57N 256 D4 2004-2010
5 Touring (E61) Eng.M57 D30 (306D2) 530 d 160kW M57 D30 (306D2) 2004-2010
5 Touring (E61) Eng.M57 D30 (306D3) 525 d 145kW M57 D30 (306D3) 2007-2010
5 Touring (E61) Eng.M57 D30 (306D3) 525 d xDrive 145kW M57 D30 (306D3) 2008-2010
5 Touring (E61) Eng.M57 D30 (306D3) 525 xd 145kW M57 D30 (306D3) 2007-2010
5 Touring (E61) Eng.M57 D30 (306D3) 530 d 155kW M57 D30 (306D3) 2005-2010
5 Touring (E61) Eng.M57 D30 (306D3) 530 d 173kW M57 D30 (306D3) 2007-2010
5 Touring (E61) Eng.M57 D30 (306D3) 530 d xDrive 173kW M57 D30 (306D3) 2008-2010
5 Touring (E61) Eng.M57 D30 (306D3) 530 xd 173kW M57 D30 (306D3) 2007-2010
5 Touring (E61) Eng.M57 D30 (306D4) 535 d 200kW M57 D30 (306D4) 2004-2010
5 Touring (E61) Eng.M57 D30 (306D5) 535 d 210kW M57 D30 (306D5) 2007-2010
5 Touring (E61) Eng.M57N 256 D4 525 d 120kW M57N 256 D4 2004-2010
7 (E65, E66, E67) Eng.M54 B30 (306S3) 730 i, Li 170kW M54 B30 (306S3) 2003-2005
7 (E65, E66, E67) Eng.730 d 150kW 2002-2008
7 (E65, E66, E67) Eng.M57 D30 (306D2) 730 d 160kW M57 D30 (306D2) 2002-2008
7 (E65, E66, E67) Eng.M57 D30 (306D3) 730 d 155kW M57 D30 (306D3) 2002-2008
7 (E65, E66, E67) Eng.M57 D30 (306D3) 730 Ld 170kW M57 D30 (306D3) 2005-2009
X3 (E83) Eng.M54 B25 (256S5) 2.5 i 141kW M54 B25 (256S5) 2004-2006
X3 (E83) Eng.M54 B30 (306S3) 3.0 i xDrive 170kW M54 B30 (306S3) 2004-2006
X3 (E83) Eng.M57 D30 (306D3) 3.0 d 160kW M57 D30 (306D3) 2007
X3 (E83) Eng.M57 D30 (306D3) xDrive 30 d 155kW 2008-2011
X3 (E83) Eng.M57 D30 (306D3) xDrive 30 d 155kW M57 D30 (306D3) 2008-2010
X3 (E83) Eng.M57 D30 (306D3) xDrive 30 d 160kW M57 D30 (306D3) 2008-2010
X3 (E83) Eng.M57 D30 (306D5) 3.0 sd 210kW M57 D30 (306D5) 2007-2008
X3 (E83) Eng.M57 D30 (306D5) xDrive 35 d 210kW 2008-2011
X3 (E83) Eng.M57 D30 (306D5) xDrive 35 d 210kW M57 D30 (306D5) 2008-2011
X3 M57306D, 2993cc, 3.0sd 2006-2016
X5 3000, M57 2003-2006

Features & Benefits

  • Genuine OEM replacement part

  • Manufactured to original factory specifications

  • Regulates alternator output voltage

  • Helps maintain proper battery charging

  • Supports stable charging system performance

  • Original fit, function, and electrical characteristics

  • Ideal for alternator rebuilding and repair

  • Engineered for long-term reliability

 

 

What Does a Voltage Regulator Do?

The voltage regulator controls the alternator's output by regulating current supplied to the rotor field winding. As electrical demand changes, the regulator continuously adjusts field current to maintain the proper charging voltage for the battery and the vehicle's electrical system.

A properly functioning voltage regulator helps prevent battery overcharging and undercharging while protecting sensitive electrical components from excessive voltage. Because charging system performance depends on the interaction between the regulator, rotor, stator, rectifier, and battery, replacing a faulty regulator is an important step in restoring alternator performance.

 

 

Common Signs Replacement Is Needed

Replace the voltage regulator if you notice:

  • Battery overcharging

  • Battery not charging

  • Low charging voltage

  • High charging voltage

  • Battery warning light illuminated

  • Intermittent charging problems

  • Headlights that brighten or dim with engine speed

  • Charging system failure during testing

  • Voltage regulator failure discovered during alternator rebuilding

 

 

Installation Recommendations

Installation should be performed by a qualified technician or experienced alternator rebuilder. Before installing the new regulator, inspect the brushes, brush holder, slip rings, rotor, stator, rectifier, wiring, and electrical connections for signs of wear or damage.

Always verify connector configuration and mounting style before installation. After assembly, bench-test the alternator to confirm proper charging voltage and overall charging system performance.

 

 

While You're Rebuilding

Inspect other common wear components to help maximize charging system reliability:

 

 

Why Buy From RC Auto Electric?

RC Auto Electric specializes in genuine OEM and premium aftermarket alternator and starter rebuilding components for professional rebuilders, repair shops, automotive technicians, and DIY enthusiasts. Our extensive catalog includes thousands of electrical components backed by accurate cross-reference information to help simplify part identification and reduce ordering mistakes.

 

 

Disclaimer

Compatibility information is provided as a reference only. Manufacturing revisions, production changes, and previous rebuilding modifications may affect internal alternator components. Always compare the original OEM part number, connector configuration, mounting style, voltage specifications, cross-reference numbers, and product photographs before installation. If you are unsure about compatibility, contact RC Auto Electric before ordering.

 

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Frequently Asked Questions

How do I confirm compatibility? +
Compare part numbers, dimensions and photos with the original component.
Is this OEM or aftermarket? +
This listing is for an aftermarket replacement part.
What should I verify before ordering? +
Check all fitment and application details before purchase.
Is professional installation recommended? +
Professional installation is recommended.
Where can I find related parts? +
Browse related starter and alternator categories on RCAutoElectric.

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