Classic Instruments SN79 ECM SIGNAL FILTER

The Classic Instruments SN79 ECM Signal Filter is designed to eliminate electrical noise and interference from electronic engine control module (ECM) signals before they reach your aftermarket gauges. This inline filter ensures accurate gauge readings by cleaning up erratic voltage signals commonly caused by ignition systems, alternators, and other electrical components in modern vehicles.

Key Features:

• Filters electrical noise from ECM output signals for stable gauge operation
• Prevents erratic needle movement and inaccurate readings on aftermarket instrumentation
• Inline design installs between ECM sensor output and gauge input
• Compact weatherproof housing for underhood or interior mounting
• Compatible with Classic Instruments gauge systems and most aftermarket gauges
• Essential for vehicles with electronic fuel injection and high-output ignition systems

This signal conditioner is particularly useful when installing aftermarket gauges in modern vehicles where electrical interference can cause gauge needles to bounce or fluctuate. The SN79 stabilizes tachometer, temperature, oil pressure, and other ECM-driven gauge signals for precise, reliable readings.