Thermo King Expansion Tank Coolant Level Sensor Switch, 42-1397 / 421397

• Precision Coolant Level Detection: Constantly monitors expansion tank fluid levels to protect diesel reefer blocks from overheating. [1, 2]
• Industrial Chemical Resistance: Formulated with premium sealing metals and premium composites to resist breakdown from anti-freeze additives and engine heat. [1]
• Direct-Fit Plug Configuration: Built exactly to factory terminal specifications for a clean, tool-free plug-and-play wiring connection.
• Prevents False Warning Codes: Eliminates erratic microprocessor faults and dashboard code alarms caused by degraded or corroded internal contacts.
• Critical Fleet Cargo Security: Mitigates the risk of sudden mid-route engine shutdown loops, securing perishable food and medical shipments.

• Reefer Expansion Tank Maintenance: Replaces failed factory screw-in sensor probes inside the primary translucent overflow reservoir.
• Preventative Fleet Servicing: Installed during comprehensive cooling system flushes or engine overhauls across transport trailer fleets.
• Diagnostic Code Resolution: Clears persistent low-fluid codes or engine protection cycles triggered by failing original electronics.
• Commercial Surplus Sourcing: High-demand replacement electronic component for transport refrigeration technicians, owner-operators, and logistics liquidation centers. [1, 2, 3]

This product was acquired by Freeman Liquidators from a sale of merchandise subject to a commercial insurance loss. Freeman Liquidators is a secondary seller of products, is not affiliated with or sponsored by the manufacturer of the products and is not a manufacturer authorized seller of the products. Sale of this product by Freeman Liquidators is not subject to the policies of the manufacturer. Any warranty offered by the manufacturer is not available to you as the purchaser.

All products are NEVER USED but external packaging will have damage. Some items may be placed into other packaging to ensure safe shipping. All items are opened for inspection prior to shipment to ensure the best quality of products. Freeman Liquidators guarantees your satisfaction. If you are not completely satisfied with a purchased product, within 30 days from the date of purchase, return the product in its packaging and Freeman Liquidators will fully refund your money.

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