

⚡ Power your ride with reliability that never quits!
The Viair 93940 is a robust 40 Amp, 12 Volt relay designed specifically for air compressors. Featuring four 1/4 inch spade connectors and a moisture-resistant molded case, it ensures a secure, durable connection and reliable performance. Ideal for automotive applications, this relay supports heavy current loads while preventing overheating, making it the go-to replacement for maintaining consistent compressor operation.
















| ASIN | B000YC7GBU |
| Best Sellers Rank | #58,667 in Automotive ( See Top 100 in Automotive ) #4 in Automotive Replacement Air Conditioning Compressor Relays |
| Brand Name | VIAIR |
| Coil Voltage | 12 Volts |
| Connector Type | Quick Connect |
| Contact Current Rating | 40 Amps |
| Contact Material | Silver Nickel |
| Contact Type | Normally Open |
| Current Rating | 40 Amps |
| Customer Reviews | 4.7 4.7 out of 5 stars (617) |
| Global Trade Identification Number | 00818114009402 |
| Included Components | Per Item Description |
| Item Weight | 0.05 Pounds |
| Manufacturer | VIAIR |
| Maximum Switching Current | 40 Amps |
| Maximum Switching Voltage | 12 Volts |
| Minimum Switching Voltage | 12 Volts (DC) |
| Model | 93940 |
| Mounting Type | Chassis Mount |
| Number of Terminals | 3 |
| Operation Mode | Automatic |
| Part Number | 93940 |
| UPC | 818114009402 |
| Unit Count | 1.0 Count |
| Warranty Description | All VIAIR products come with a One Year Manufacturer Defect Warranty |
| Wattage | 480 watts |
M**.
Exactly what I needed to fix my ARB single compressor
I bought this relay to replace the failed relay in my ARB single air compressor, and it’s been working great. I was a little worried about compatibility at first, but it dropped right in with no issues and got my compressor back up and running immediately. Since installing it, the compressor has been starting normally and running consistently. No weird behavior, no overheating, and no problems after multiple uses. I’ve used it several times now to air up tires and it’s been solid every time. The relay itself feels well made and reliable, which is really all you can ask for in a replacement part like this. If you’re dealing with a bad relay in a compressor or another automotive application, this is a simple and effective fix. I’m very happy with it and would definitely buy it again.
A**R
Happy dad
My dad said that he's happy with his item, works amazing.
D**N
Repair Robot
Great Product. Solved our problem!
M**T
Other than that looks like a high quality relay compared to the other ones ...
Not entirely the vendors fault but please note that this is a 4 prong/post relay. It's missing the center connection so can't use it for my application. Other than that looks like a high quality relay compared to the other ones I've got from EBay and such.
L**E
Works on my 2014 Jeep Wrangler
It’s worth the money
A**N
Perfect ARB replacement
My ARB compressor wouldn’t switch on and fortunately it was just a bad relay after years of being in a hot engine bay. 5x cheaper and delivered in one-day thanks to Amazon. Going to order a spare to keep in the truck in the event it fails in the backcountry.
A**R
Perfect for Air Lift systems
These are a great replacement relay for anyone with an air lift performance system. We've all been there when something goes weird just to find out the relay is bad. Quick switch out and direct fit.
D**.
Plug & play for ARB air compressor
My ARB single-stage compressor under my hood was super intermittent. The original relay had been in there for about 6 years. Popped this one in and it works good as new again.
J**N
Been on for almost a year now and still works fine, plastic mounting tabs usually worry me but this one is sturdy.
A**R
The items works perfect for what is meant for
N**A
Came quickly and worked perfect
S**W
Simple, inexpensive robust (40 amps). I use it to run my bilge pump to cut down on burning out bilge pump switches. I have used other realys for this purpose, the all seem to work OK, but this was a very good price and most other relays are only 30 amps. I don't know if there is really a difference, but will go with the specs. arks are arks, the bigger the contacts the longer they last. Of course with all of this kind of stuff, until it has been in for a few years we really don't know do we? But it looks good so far.
G**F
Seems fine
Trustpilot
1 month ago
1 month ago