CDI Unit for Yamaha 9.9HP 15HP 2-Stroke Outboard | 6B4-85540-00

Product Overview

Replacement 8-wire CDI ignition unit for compatible Yamaha 9.9HP and 15HP 2-stroke outboard engines.

Designed to replace Yamaha OEM 6B4-85540-00, this CDI module is intended for compatible marine ignition systems using the same wiring, connector configuration, mounting dimensions, and original CDI design.

The unit measures approximately 77 × 59 × 21mm with an approximately 77mm mounting-hole distance.

Before ordering, verify the OEM number, engine model, 8-wire configuration, connectors, mounting dimensions, and original CDI appearance.

Product Compatibility

Make	Engine	Engine Type	Fitment Notes	OEM Reference
Yamaha	9.9HP	2-Stroke Outboard	Selected compatible models	6B4-85540-00
Yamaha	15HP	2-Stroke Outboard	Selected compatible models	6B4-85540-00

Important: This CDI should not be selected by horsepower alone. Yamaha used different ignition modules across 9.9HP and 15HP outboard engine families.

Match OEM 6B4-85540-00 and compare the original CDI before ordering.

OEM Cross-Reference Numbers

Yamaha

• 6B4-85540-00
• 6B4-85540-00-00

The extended -00-00 format may appear in Yamaha parts catalogs or dealer listings for the same base part reference.

Specifications

Specification	Details
Product Type	CDI Unit / Ignition Module
OEM Reference	6B4-85540-00
Engine Type	2-Stroke Outboard
Listed Horsepower	9.9HP / 15HP
Wiring	8-Wire
Length	77 mm / 3.03 in
Width	59 mm / 2.32 in
Height	21 mm / 0.83 in
Mounting Hole Diameter	13 mm / 0.51 in
Mounting Hole Distance	77 mm / 3.03 in
Housing Material	ABS
Application	Yamaha Outboard Motor
Condition	New
Package Quantity	1 CDI Unit

Key Features

• 8-Wire CDI Configuration: Designed for compatible Yamaha 2-stroke outboard ignition systems.
• OEM-Specific Replacement: Replaces Yamaha 6B4-85540-00.
• 9.9HP / 15HP Application: Intended for selected compatible Yamaha outboard engines.
• Marine Ignition Component: ABS housing provides protection for the internal electronic components.
• Fitment Reference Dimensions: 77 × 59 × 21mm housing and approximately 77mm mounting-hole spacing help confirm compatibility.