This is a set of 12V 40A five-pin automotive relays with pre-wired sockets, used to switch high-current accessories such as spotlights, fans and pumps from a low-current dash switch.
What’s in the box
- 12V 40A five-pin relays, each with a metal mounting tab
- A matching socket for each relay with five colour-coded wire leads (blue, red, black, yellow and white)
- Quantity per set: please confirm with us before ordering
Key features
- Rated 12V DC, 40A (marked on each relay)
- Five terminals: 30, 85, 86, 87 and 87a, as shown on the relay’s pin diagram
- Changeover (SPDT) layout: 87 is the normally open output and 87a the normally closed output
- Pre-wired socket, so there is no need to crimp onto bare relay blades
- Metal tab with a hole for screwing or bolting the relay down
Typical uses
- Spotlights, driving lights and light bars
- Electric radiator fans
- Electric fuel pumps and horns
- Any 12V accessory that draws more current than a dash switch should carry
Installation notes
Check the pin diagram on the relay rather than relying on wire colour alone, as colour conventions vary between suppliers. Fit an in-line fuse rated for the circuit as close to the battery as practical, use cable sized for the load, and mount the relay where it is protected from water and heat. If you are unsure about wiring, the Menin Motorsport workshop in Mayville, Pretoria can fit it for you.
Frequently asked questions
What voltage and current are these relays rated for?
Each relay is marked 12V and 40A.
What is the difference between pins 87 and 87a?
Pin 87 is connected to pin 30 when the coil is energised, and pin 87a is connected to pin 30 when the coil is off. This lets you switch one circuit on, or switch between two circuits.
Do the relays come with sockets?
Yes. Each relay comes with a socket fitted with five wire leads.
