Alternator for DENSO OEM Reference Number 104211-3910 Lester 11931 12V 135A

The Main Parameters:

Key Features:

• Vehicle application: Select Honda cars and trucks (Civic, HR‑V)

• Voltage: 12 volts

• Rated output: 135 amps

• Design Spec: IR/IF, Hairpin winding, Clock 3, Side‑mount plug, SD7 decoupler pulley, 58 mm pulley OD, Clockwise (CW) rotation

• Cross‑reference OEM & aftermarket part numbers:

• DENSO OEM reference: 104211‑3910

• Lester reference: 11931; WAI reference: 11931N

• Honda OE numbers: 06311‑5BA‑505RM, 31100‑5BA‑A01, 31100‑5BA‑A01RM, CSP91

• Direct‑replacement design: Built to match the specified application and original charging‑system requirements

• Reliable electrical performance: Helps maintain proper battery charge and consistent system voltage

• High‑output capacity: 135‑amp output supports vehicles equipped with multiple electrical accessories and factory electronics

• OEM‑style fit and function: Intended for straightforward replacement when the application, mounting configuration, pulley, and electrical connections match

Introduction

A properly functioning alternator is essential for keeping the battery charged and supplying power to the vehicle while the engine is running. This 135‑amp Denso hairpin‑style alternator is engineered for use in select Honda automotive and truck applications requiring the DENSO 104211‑3910, Lester 11931, or corresponding Honda OE part numbers.

The unit features IR/IF internal design, side‑positioned electrical plug, SD7 decoupler pulley with 58 mm outer diameter, and clockwise rotation, matching original factory hardware specifications. It is designed to provide dependable charging performance for everyday driving, including operation of headlights, climate‑control systems, infotainment equipment, safety systems, and other vehicle electronics. Its 12‑volt configuration and 135‑amp rating make it a suitable replacement for vehicles equipped with the corresponding original alternator specification.

Confirmed Vehicle Fitments:

• Honda Civic L4 1.5L (L15BY) — 2023

• Honda Civic L4 2.0L — 2024

• Honda Civic L4 2.0L K20C2 — 2016‑2023

• Honda HR‑V L4 2.0L — 2024‑2026

• Honda HR‑V L4 2.0L K20Z5 — 2023

Replacing a weak or failed alternator can help address symptoms such as a battery warning light, dimming headlights, slow electrical accessories, repeated battery discharge, or difficulty starting caused by an undercharged battery.

> Note: This unit shares most features with part number 290‑5734; the primary difference is pulley configuration.

Compatibility

This alternator is intended for select Honda Civic and HR‑V cars and trucks. Compatibility may vary by model year, engine, trim level, charging‑system configuration, connector, pulley arrangement, and mounting design.

Before ordering, compare the following information with the alternator being replaced:

• OEM or manufacturer part number (DENSO, Honda, Lester, WAI cross‑reference numbers)

• Lester / WAI aftermarket reference number

• Rated amperage (135A), rotation direction and pulley dimensions

• Mounting points and dimensions

• Electrical connector configuration: Plug Clock 3, Plug Code 501, Side‑oriented plug

• Pulley design: SD7 decoupler pulley, 58 mm outer diameter

• Regulator and charging‑system specifications

The vehicle’s year, make, model, engine, and existing alternator information should always be verified to ensure proper fitment. Do not rely solely on vehicle year/make/model; always cross‑check the old unit’s part numbers and physical hardware.

Important Fitment Note

Part numbers are provided for identification and cross‑reference purposes. Confirm application compatibility before installation. A professional installation is recommended, and the battery, cables, grounds, belt condition, and charging‑system connections should be inspected whenever an alternator is replaced. Mismatched pulley, plug orientation or rotation will result in non‑functional fitment even if the vehicle model appears to match.

FAQ:

Q1. How long is your delivery time?

A: Generally it takes 45-60 days if the goods are out of stock. If it is in stock, it takes 7 days.

Q2. Do you provide samples ? is it free or extra ?

A: Samples are available. Buyer covers sample cost and freight; sample cost is refundable on bulk order.

Q3. What are your terms of packing?

A: Generally, we pack our goods in neutral cartons. If you have a legally registered patent, we can pack the goods in your branded boxes after getting your authorization letters.

Q4. Do you test all your goods before delivery?

A: Yes, we have 100% test before delivery.

Q5.How about your warranty?

A:Our warranty is one year.