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Small black plastic Honda antenna adapter with coaxial connectors

METRA

METRA 40-HD31 Honda antenna adapter for FM modulator audio component

SKU CH-7251-ZR1NG

Connects factory satellite antenna to FM modulator using 40-HD31 adapter

  • Adapts the factory satellite antenna connector for FM modulator use
  • Designed with the user and installer in mind for straightforward setup
  • Tested for function in a real world environment to ensure reliable performance
  • Compatible with Honda vehicles requiring antenna adaptation
  • Enables FM modulator integration without modifying the original antenna connection

Honda antenna adapter for FM modulator

The Metra 40-HD31 connects a factory satellite antenna connector to an FM modulator. It is designed for installers and vehicle owners adding an aftermarket audio source to a Honda system. The part bridges the proprietary antenna interface so the modulator can receive the signal cleanly.

Practical limits of the factory antenna connector

The adapter works only with the specific Honda satellite antenna plug it was built to match. It does not convert other antenna types or provide signal amplification. Installers must verify the vehicle connector matches before fitting. No additional wiring or power is required for the connection.

Model numbers 31 and 40

The product is identified by the numbers 31 and 40 in the Metra catalogue. These codes confirm the correct application for the intended Honda antenna interface. Using a different code risks a physical or electrical mismatch. Buyers should cross-reference these numbers with their vehicle documentation.

Highlights

  • Adapts the factory satellite antenna connector for FM modulator use
  • Designed with the user and installer in mind for straightforward setup
  • Tested for function in a real world environment to ensure reliable performance
  • Compatible with Honda vehicles requiring antenna adaptation
  • Enables FM modulator integration without modifying the original antenna connection

Specifications

No published specifications for this item yet.

Questions about this item

Should I pick the 40-HD31 adapter or another Metra part for my Honda?

The 40-HD31 is the specific Metra adapter built to connect a factory Honda satellite antenna connector to an FM modulator.

What does the 40-HD31 actually do once it is plugged into the car?

It converts the Honda factory satellite antenna plug so an FM modulator can use the vehicle's existing antenna signal for audio playback.

Which antenna connector standard does the 40-HD31 adapt, and what does that limit?

It adapts the proprietary Honda satellite antenna connector; the adapter only passes the antenna signal to the FM modulator and does not carry power or data.

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