Standard Ignition FLS-1 Engine Coolant Level Sensor

Engine Coolant Level Sensor for GM Applications

Standard Ignition FLS-1 is an engine coolant level sensor built for accurate coolant monitoring in select Chevrolet, Pontiac, Buick, Cadillac, Oldsmobile, and GMC vehicles. It uses a plug-in connector with a male blade terminal and 12-volt electrical design for straightforward service replacement.

Fits 1984-2000 Chevrolet Camaro, Caprice, Monte Carlo, Impala, Corsica, Cavalier, G20, Metro; 1985-1988 Pontiac Firebird, Grand Am, Tempest, 6000, Safari; and additional GM applications listed below. Standard Ignition FLS-1 is also a direct reference for service part searches that call out FLS1.

Key Features

• Engine coolant level sensor for monitoring coolant level in the reservoir or tank circuit
• Plug-in connector design with male connector gender
• Male blade terminal with 1 terminal for simplified electrical connection
• 12-volt electrical specification
• Built with copper alloy conductors for strong electrical conductivity and low resistive loss
• 100% tested for mechanical switching and electrical switching performance
• Robust construction and high-grade materials for service use

Detailed Description

Standard Ignition FLS-1 is an engine coolant level sensor engineered for dependable coolant level signaling in a wide range of GM cars and vans. It is a practical replacement choice for Chevrolet Camaro, Chevrolet Caprice, Pontiac Firebird, Pontiac Grand Am, Buick Skylark, and GMC G2500/G3500 applications where the original sensor uses a plug-in, male-terminal configuration. This part number, FLS-1, is built with copper alloy conductors and tested for both mechanical and electrical switching performance to support consistent operation in service environments.

This part cross-references 5S1446 and 71-3555 for the same application.

What It Helps Address

• Coolant level warning light staying on
• Intermittent or inaccurate coolant level readings
• Electrical connection issues at the sensor terminal
• Replacement needs after sensor wear or internal switch failure
• Service repairs on GM coolant level monitoring systems

Installation Notes and Tips

• Verify connector style, terminal type, and voltage before installation.
• Confirm vehicle-specific fitment by year, make, and model before ordering.
• Inspect the connector and harness for corrosion or damaged terminals during replacement.
• Check coolant level and system condition after installation to confirm proper sensor operation.

Quality Assurance

Standard Ignition builds this sensor with durable materials and tests each unit for mechanical and electrical switching performance. The design reflects long-term product development focused on technician service needs.