--- product_id: 25310175 title: "20904439 Trailer Brake Continue Relay Assembly" brand: "gm genuine parts" price: "¥28146" currency: JPY in_stock: true reviews_count: 13 category: "Gm Genuine Parts" url: https://www.desertcart.jp/products/25310175-20904439-trailer-brake-continue-relay-assembly store_origin: JP region: Japan --- # 1.73W ultra-efficient power Exact OE fit for GM vehicles 24-month unlimited mile warranty 20904439 Trailer Brake Continue Relay Assembly **Brand:** gm genuine parts **Price:** ¥28146 **Availability:** ✅ In Stock ## Summary > 🚛 Keep your trailer brakes flawless—because your ride deserves genuine precision! ## Quick Answers - **What is this?** 20904439 Trailer Brake Continue Relay Assembly by gm genuine parts - **How much does it cost?** ¥28146 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/25310175-20904439-trailer-brake-continue-relay-assembly) ## Best For - gm genuine parts enthusiasts ## Why This Product - Trusted gm genuine parts brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Backed by Trusted Warranty:** Enjoy peace of mind with a 24-month unlimited mile limited warranty, reflecting GM’s commitment to quality. - • **Plug-and-Play Installation:** Exact OE replacement ensures hassle-free setup—no modifications needed, saving you time and stress. - • **Reliable Trailer Brake Control:** Electro-mechanical relay guarantees smooth, automatic trailer brake operation, eliminating warning lights and annoying alerts. - • **Durable Silver Contact Material:** Premium silver contacts provide superior conductivity and long-lasting performance under heavy-duty conditions. - • **Precision Engineered for GM Excellence:** Designed and validated by GM engineers for seamless integration with Chevrolet, Buick, GMC, and Cadillac models. ## Overview The GM Genuine Parts 20904439 Trailer Brake Continue Relay Assembly is an OE-quality electro-mechanical relay designed specifically for GM vehicles. Engineered and rigorously tested by GM, it ensures reliable trailer brake control, eliminates warning alerts, and features durable silver contacts. With an exact fit and a 24-month unlimited mile warranty, it’s the trusted choice for professional-grade trailer brake maintenance. ## Description GM Genuine Parts Trailer Tow Relays are designed, engineered, and tested to rigorous standards, and are backed by General Motors. These relays function as an electro-mechanical switch containing a coil and set of connection points. These trailer tow relays provide a variety of control functions for a vehicle's trailer brake system. GM Genuine Parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment (OE). Review: Exact fit , works great ! - This worked great ! Took away the service trailer brake and check trailer brake wiring warning light and annoying dinging on my 2012 Chevy Silverado. Easy to install. Exact part match. Fit perfect ! Review: Good results. - Works great for fair price. Good ## Features - Some GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment (OE) - GM Genuine Parts are designed, engineered and tested to rigorous standards, and are backed by General Motors - GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle - GM regularly updates production and service part designs to integrate new materials and technologies ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00559VPK0 | | Best Sellers Rank | #39,410 in Automotive ( See Top 100 in Automotive ) #8 in Trailer Brake Assemblies | | Brand | GM GENUINE PARTS | | Brand Name | GM GENUINE PARTS | | Connector Type | Spade | | Contact Material | Silver | | Contact Type | Online_sales | | Customer Reviews | 4.7 out of 5 stars 2,156 Reviews | | Global Trade Identification Number | 00707773710814 | | Included Components | 20904439 | | Item Type Name | RELAY ASM-TRLR BRK CONT | | Manufacturer | ACDelco | | Model | 20904439 | | Mounting Type | None" or "PCB Mount | | Operation Mode | Automatic | | Part Number | 20904439 | | UPC | 707773710814 | | Unit Count | 1.0 Count | | Warranty Description | 24 Month / Unlimited Mile Limited Warranty on parts sold on or after 04/01/18. (Parts Only) Please see ACDelco.com for more details. | | Wattage | 1.73 watts | ## Product Details - **Connector Type:** Screw - **Contact Material:** Silver - **Contact Type:** Online_sales - **Mounting Type:** None" or "PCB Mount - **Brand:** GM GENUINE PARTS ## Images ![20904439 Trailer Brake Continue Relay Assembly - Image 1](https://m.media-amazon.com/images/I/41EqyZlGe-L.jpg) ![20904439 Trailer Brake Continue Relay Assembly - Image 2](https://m.media-amazon.com/images/I/41eNncAUBFL.jpg) ![20904439 Trailer Brake Continue Relay Assembly - Image 3](https://m.media-amazon.com/images/I/31dTQGQhwfL.jpg) ![20904439 Trailer Brake Continue Relay Assembly - Image 4](https://m.media-amazon.com/images/I/31Jhuj+bCaL.jpg) ## Questions & Answers **Q: Why do brakes need to be replaced in the first place?** A: Friction material on the brake pad contacts the rotors to slow the vehicle. In time, that material wears away and the pads must be replaced. Sometimes the rotors and calipers must also be replaced. **Q: What’s the squealing sound I hear when braking?** A: Over time, wear indicators in brake pads may contact the rotors’ surface when braking, resulting in a metallic squealing sound. Vehicles equipped with wear sensors may also provide an alert that minimum brake pad thickness has been reached. **Q: What if it’s more of a grinding sound?** A: If all the friction material has been worn away, the metal backing plate of the brake pad will be the material in contact with the rotor during braking. It causes a grinding sound and braking performance is often diminished. **Q: Why do the brakes seem to pulsate when stopping?** A: It may be due to worn brake pads, unevenly worn rotors or unevenly worn tires. Have the pulsation diagnosed as soon as possible to avoid the possibility of greater brake system wear or damage. **Q: What about vibrations or shaking in the steering wheel?** A: This is more serious than pulsation. If the brakes are very worn or the rotors are unevenly worn, there can be a significant vibration or shaking in the steering wheel when braking. It may mean brake service is needed immediately. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Exact fit , works great ! *by K***R on February 17, 2026* This worked great ! Took away the service trailer brake and check trailer brake wiring warning light and annoying dinging on my 2012 Chevy Silverado. Easy to install. Exact part match. Fit perfect ! ### ⭐⭐⭐⭐⭐ Good results. *by J***F on April 1, 2026* Works great for fair price. Good ### ⭐⭐⭐⭐⭐ simple fix to annoying service trailer brake light easy *by H***E on May 11, 2025* fixed the issue ..i have had a service trailer brake light message on for over a year its on a 2013GMC Sierra i don't use trailer brakes so was not worried much just annoyed at light on all the time .i started looking on line for problems that might happen and most were saying bad wire or plug .after tracing out all the wires and checking the plug i found nothing wrong so then i decided to ask the dealer GMC there thinking on it .all i got from dealer was bring it in and we can check run test for about 400 plus parts and later found that these parts are a problem and they new this and never told me there was a bulletin out from GMC( ripoffs ).so i said no thanks .so back to the web and seen this part on amazon checked thru the reviews and decided to change part .most people said easy change and fixed the problem of service trailer brake .from start to finish it took 10 minutes to install .all i had to do was lower spare loosen 2 star screws remove plug and install new .it was that easy it took longer for me to find my star driver then to change the part .so if you have the same issue i would first just look at the wires for something torn loose ya never know ,and start with this part first .i am 100 percent pleased and everything is working perfect no more service trailer brake light .easy fix thanks for everyones post hope this one helps .also the part fits many years GMC /chevy models trucks and cars . ## Frequently Bought Together - General Motors GM 20904439 Trailer Brake Continue Relay Assembly - GM Genuine Parts 15926102 Trailer Brake Control Switch Assembly - GM Parts 20850923 Trailer Brake Control Module Assembly --- ## 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.jp/products/25310175-20904439-trailer-brake-continue-relay-assembly](https://www.desertcart.jp/products/25310175-20904439-trailer-brake-continue-relay-assembly) --- *Product available on Desertcart Japan* *Store origin: JP* *Last updated: 2026-07-21*