--- product_id: 4141102 title: "Viair 93940 40 Amp Air Compressor Relay for 12 Volt compressor , Black" brand: "viair" price: "S/.47" currency: PEN in_stock: true reviews_count: 13 category: "Viair" url: https://www.desertcart.pe/products/4141102-viair-93940-40-amp-air-compressor-relay-for-12-volt store_origin: PE region: Peru --- # 40 Amp max current Moisture-resistant molded case Four 1/4 inch spade connectors Viair 93940 40 Amp Air Compressor Relay for 12 Volt compressor , Black **Brand:** viair **Price:** S/.47 **Availability:** ✅ In Stock ## Summary > ⚡ Elevate your compressor game with power and precision! ## Quick Answers - **What is this?** Viair 93940 40 Amp Air Compressor Relay for 12 Volt compressor , Black by viair - **How much does it cost?** S/.47 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.pe](https://www.desertcart.pe/products/4141102-viair-93940-40-amp-air-compressor-relay-for-12-volt) ## Best For - viair enthusiasts ## Why This Product - Trusted viair brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Reliable & Ready to Run:** Trusted by pros for consistent, overheating-free operation - • **Plug & Play Quick Connects:** Four 1/4 inch spade posts for seamless installation - • **Built to Brave the Elements:** Moisture-resistant casing ensures durability in tough conditions - • **Power-Packed 40 Amp Capacity:** Handles heavy-duty 12V compressor loads with ease - • **Precision Fit for Every Compressor:** Each compressor needs its own relay for optimal performance ## Overview The Viair 93940 is a robust 40 Amp, 12 Volt relay designed specifically for air compressors. Featuring four quick-connect spade terminals and a moisture-resistant molded case, it ensures reliable, long-lasting performance. Ideal for automotive and compressor applications, this relay guarantees consistent operation and easy installation, backed by a one-year manufacturer warranty. ## Description Viair 40 ampere four-post relay for all 12-volt applications. Review: GOOD DEAL - ALL GOOD EXACTLY AS DESCRIBED. SUPER FAST DELIVERY WORKS GREAT Review: 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. ## Features - 40 Amp 12v Relay with Mounting Tabs - Four 1/4 inch spade post connectors - Handles up to 40 amperes maximum ampere draw in applications - Each compressor must have its own relay for a proper installation - Mounting tab for relay molded into moisture resistance relay case ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B000YC7GBU | | Best Sellers Rank | #47,951 in Automotive ( See Top 100 in Automotive ) #4 in Automotive Replacement Air Conditioning Compressor Relays | | Brand | VIAIR | | Brand Name | VIAIR | | Coil Voltage | 12 volts | | Connector Type | Quick Connect | | Contact Current Rating | 40 A | | Contact Material | Silver Nickel | | Contact Type | Normally Open | | Current Rating | 40 A | | Customer Reviews | 4.7 out of 5 stars 628 Reviews | | Global Trade Identification Number | 00818114009402 | | Included Components | Per Item Description | | Item Weight | 22.68 g | | Manufacturer | VIAIR | | Maximum Switching Current | 40 A | | Maximum Switching Voltage | 12 volts | | Minimum Switching Voltage | 12 volts_of_direct_current | | Model | 93940 | | Mounting Type | Chassis Mount | | Number of Terminals | 3 | | Operation Mode | Automatic | | Part Number | 93940 | | UPC | 818114009402 | | Unit Count | 1 Count | | Warranty Description | All VIAIR products come with a One Year Manufacturer Defect Warranty | | Wattage | 480 watts | ## Product Details - **Connector Type:** Quick Connect - **Contact Material:** Silver Nickel - **Contact Type:** Normally Open - **Current Rating:** 40 Amps - **Mounting Type:** Chassis Mount ## Images ![Viair 93940 40 Amp Air Compressor Relay for 12 Volt compressor , Black - Image 1](https://m.media-amazon.com/images/I/61OsFO9ivIL.jpg) ## Questions & Answers **Q: Would this work on a Mercedes benz s430 airmatic compressor** A: is it 40 amps or less then it should **Q: Will this relay work for a Mercedes R350** A: relays see amperage only, so if what you are trying to control does not draw more than the rated amperage of the relay, then yes **Q: I just bought this relay to go with the viair high flow 150 set up. But it only has a pos and neg wire will the relay work?** A: Yes it should work. The purpose of a relay is to allow the use of smaller gauge wire for the pressure switch input from the pressure tank and on/off switch, however, you need to use an appropriately sized wire from your battery or another high amperage source direct to the compressor. The item shown is for 40 amp delivery and if this is the draw for your compressor, you should be looking at wire in the 8 gauge range for both positive and to chassis ground or all the way back to the battery. If the compressor draw is less, like something in the 15 or 20 amp range, you can still use this relay and use 14 gauge (for 15 amp draw) or 12 gauge (for 20 amp draw) for the main positive and negative run to the compressor. As stated above, the ancillary wiring for pressure switch, on/off switch can be much smaller wire gauge. An internet search should have wiring diagram info for high amp devices and possibly the Viair website. Be aware that I am NOT an electrician so do not blindly follow my input. Hope this helps somewhat. **Q: Will it fit a R350** A: that I can't tell. ## Customer Reviews ### ⭐⭐⭐⭐⭐ GOOD DEAL *by T***S on May 20, 2026* ALL GOOD EXACTLY AS DESCRIBED. SUPER FAST DELIVERY WORKS GREAT ### ⭐⭐⭐⭐⭐ Exactly what I needed to fix my ARB single compressor *by M***. on December 12, 2025* 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. ### ⭐⭐⭐⭐⭐ Relay *by M***T on March 23, 2026* Works in a arb air compressor. ## Frequently Bought Together - Viair 93940 40 Amp Air Compressor Relay for 12 Volt compressor , Black - Parts Express 330-075 12 VDC 5-Pin Relay Socket For Bosch Type Relay - Viair 90223 Pressure Switch, Black 1/8 in. NPT (M) 12 gauge --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.pe/products/4141102-viair-93940-40-amp-air-compressor-relay-for-12-volt](https://www.desertcart.pe/products/4141102-viair-93940-40-amp-air-compressor-relay-for-12-volt) --- *Product available on Desertcart Peru* *Store origin: PE* *Last updated: 2026-07-30*