Direct Drop-in Replacement Identified

Song Chuan 303-1AH-C-R1-U01-12VDC crosses to HongFa

Chief stocks and distributes a direct drop-in replacement for Song Chuan automotive relay 303-1AH-C-R1-U01-12VDC. Hongfa part number HFV11/12-HS-R(257) is a micro 280 style relay capable of operating up to 20A at 12VDC. Single Pole, Single Throw (SPST) form.

HFV11/12-HS-R(257) Specifications

ManufacturerHongFa, Inc.
Product CategoryAutomotive Relay
Coil Voltage12 VDC
Max Amperage20A
Contact FormSPST (1 Form A)
Vibration Resistance10Hz - 40Hz 1.27mm DA
Shock Resistance196m/s2
ConstructionPlastic Sealed, Dust Protected

How to Choose a Replacement Automotive Relay

Having trouble finding a replacement for an automotive relay? Follow the steps below when choosing a drop-in replacement.

  • Determine the voltage. In the case of automotive relays the voltage is typically 12V, 24V or higher.
  • Determine the relay layout. Common automotive relay layouts are SPST (Single Pole Single Throw) which is designated with 4 pins, or SPDT (Sing Pole Double Throw) which is 5 pins.
  • Determine the footprint. Commonly used footprints for plug-in automotive relays are ISO Ultra Micro, ISO Micro 280, ISO Micro, ISO Mini, or ISO Maxi. Automotive applications also use PCB layouts. See image below for layout diagrams.

  • Determine the continuous rating; for reference, automotive relays are generally between 20A and 75A
  • Specify mounting options: bracket or no bracket
  • Finally, determine the suppression. Suppression options are a resistor, a diode or no suppression.
Keep in mind when cross referencing relays it is important to match the coil voltage, match or exceed the current rating and select the same supression type. After identifying these important specifications you are ready to find a suitable replacement automotive relay.