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Automann · Electrical & Lighting
178.55510
In stock · ships from Knoxville
This is a 12-volt, 40-amp Mini ISO relay with a normally closed (SPST-NC) contact configuration.
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Verified fitment for 2 applications
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All confirmed applications for this part number.
Freightliner
International
Freightliner
International
Fits select heavy-duty International and Freightliner models where these OEM relays are specified. Always verify your truck’s factory relay part number.
Part data verified against 2 catalog sources
Numbers this part supersedes or interchanges with. Showing 6 of 6.
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It is designed to control high-current circuits in heavy-duty trucks, such as engine shutdown, starter, or safety interlock systems. The relay is normally closed and opens when the coil is energized, making it suitable for fail‑safe applications where a circuit should remain powered until the relay is activated. Replacement is needed when the relay fails, causing electrical components to stay off or remain constantly powered when they shouldn’t. It directly replaces International 2503522C1, Freightliner VF4-12F21-Z02, and MEI 1269 relays.
Part Number: 178.55510
RELAY ISO MINI 4 PIN 12V 40A SPST-NC-IHC
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside electrical & lighting
