Aftermarket Valeo Voltage Regulator M646

Specifications MFR: VALEO FEATURE 1:100% New  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 Features & Benefits Precision aftermarket replacement part Regulates alternator output voltage Helps maintain proper battery charging Supports stable charging system performance Manufactured to match original specifications Designed for dependable long-term operation Ideal for alternator rebuilding and repair Cross-referenced to OEM and aftermarket part numbers 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: Bearings Brushes Brush Holder Slip Rings Rectifier Diodes Rotor Clutch Pulley Insulators Why Buy From RC Auto Electric? RC Auto Electric specializes in alternator and starter rebuilding components for professional rebuilders, repair shops, automotive technicians, and DIY enthusiasts. Our extensive catalog includes thousands of OEM and aftermarket 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 part, 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.