Mercury – Dual-Helm Malfunction Light Harness | 10-Foot Cable | 84-8M0048040

Overview

Dual-helm boats need a clean way to send catalyst-warning signals to the dash light at the upper or secondary helm. The Mercury 84-8M0048040 Dual Helm Malfunction Light Harness provides a 10-foot connection dedicated to dual-helm layouts, ensuring the catalyst malfunction light receives the proper OBDM alert from any catalyst-equipped MerCruiser engine. It keeps the warning circuit reliable, clear, and ready to alert you the moment the system detects a problem.

Key Features

• 10-Foot Dual-Helm Harness – Sized for secondary or upper-helm routing on dual-helm boats.
• OBDM Alert Path – Carries catalyst malfunction signals directly to the dash-mounted indicator.
• Catalyst-Engine Compatible – Works with all MerCruiser engines equipped with a catalyst system.
• OEM Connector Fit – Mercury factory connectors ensure proper alignment and a secure hold.
• Flexible Routing – Ideal length for upper-helm runs or short secondary console paths.
• Reliable Warning Delivery – Ensures your malfunction light activates as soon as a fault is detected.

Compatibility

• All catalyst-equipped MerCruiser engines
• Dash-Mounted Catalyst Malfunction Light (8M0046481)
• Dual-helm installations requiring a 10-foot harness

Performance & Practical Benefits

This harness gives dual-helm vessels a clean way to extend the catalyst-warning signal to a second station. With 10 feet of length, it fits neatly into upper-helm or co-pilot helm layouts and routes easily through console structures. Once connected, the malfunction light functions just like the primary helm light—giving you a clear, immediate visual alert anytime the catalyst system requires attention.

Why Buy OEM

Catalyst alerts are tied directly to emissions and engine-protection diagnostics. Mercury’s OEM harness ensures the signal arrives cleanly with no interference or incorrect wiring logic. Aftermarket connectors often cause false alarms or missed warnings, but this factory-built harness provides the reliability and durability needed in a marine environment.

FAQ

Q1: What does this harness connect?
It links the engine’s OBDM catalyst-alert circuit to the malfunction light at a secondary helm.

Q2: Why choose the 10-foot dual-helm version?
It’s ideal for upper helms, tower helms, or secondary consoles that sit close to the primary routing path.

Q3: Will it work with all MerCruiser engines?
Yes—so long as the engine is catalyst-equipped.

Q4: Is the malfunction light included?
No. The dash light is sold separately as part number 8M0046481.

Q5: Is installation difficult?
No. It plugs in easily using OEM connectors and routes like any Mercury harness.