Bosch 1986AE0040 Alternator Voltage Regulator 12V LIN B-Circuit

The Bosch 1986AE0040 is an OEM-grade alternator voltage regulator engineered for 12-volt electrical systems. Manufactured in Germany by Robert Bosch GmbH — the world's largest automotive supplier — this regulator delivers precise voltage control for three-phase alternators, maintaining a default regulated output of 14.4 volts to protect sensitive vehicle electronics and ensure reliable battery charging.

This unit uses a LIN (Local Interconnect Network) communication protocol with a B-circuit design, making it compatible with computer-controlled charging systems. It features LIN-NA terminals, soft-start technology, and load response control (LRC) for smooth integration with modern engine management systems. Field short circuit protection adds an extra layer of electrical safety.

Key Features:

• OEM Bosch quality, manufactured in Germany
• Rated voltage: 12V | Operating voltage: 14.4V
• LIN (COM) protocol, ID 56, 19200 bps communication speed
• B-circuit design with LIN-NA terminals
• Computer-controlled with soft-start and LRC (Load Response Control)
• LIN or stator activated operation
• Field short circuit protection
• Plug type: PL_2306

Cross-Reference Part Numbers:

• Bosch: F00M346008, F00M346021, F00M346037, F00M346047, F00M346080, F00M144288
• Mercedes-Benz OEM: A0031546806, 0031546806
• Other: ARE0077, IB6037, 130417, 332016, 335028, VR-B021, CQ1011573

This Bosch voltage regulator is a direct OEM replacement that meets or exceeds original equipment specifications, ensuring dependable alternator performance and long-term electrical system reliability.