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Red Dot · Electrical & Lighting
RD-5-9915-0P
In stock · ships from Knoxville
This is a heavy-duty 12-volt SPDT (Single Pole Double Throw) relay with an integrated diode, typically used in mobile HVAC systems on commercial trucks.
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Verified fitment for 5 applications
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All confirmed applications for this part number.
Chevrolet
Freightliner
GMC
Peterbilt
Western Star
Chevrolet
Freightliner
GMC
Peterbilt
Western Star
Commonly used in HVAC systems on these truck makes. Always confirm connector type and pin configuration before ordering.
Part data verified against 3 catalog sources
Numbers this part supersedes or interchanges with. Showing 9 of 9.
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It switches high current—up to 40 amps when making, 30 amps when breaking—to control components such as blower motors or compressor clutches. The built-in diode suppresses voltage spikes that can damage sensitive electronics in modern vehicle circuits. You would replace it when an air conditioning or heating system fails to engage, or if the existing relay shows signs of burning, corrosion, or intermittent operation.
Part Number: RD-5-9915-0P
RELAY- 12V WITH DIODE (71R1722)
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside electrical & lighting
