RT911 Automotive Relay Tester RT911 Automotive Relay TesterRelay Tester

The design of this product feels really good and the included battery clips give a secure connection without fiddling around. The cords are a little on the thinner side so be careful not to wear them down while using them.One thing worth mentioning is that it’s not exactly a “plug and play” gadget for absolute beginners. You still need to have some basic understanding of relays and wiring to make full use of it, otherwise the test results won’t mean much. That said, if you’re comfortable with automotive electrical work, this tool is a great addition to the kit. I have an older car with a headlight that I wasn’t sure what was wrong with it. So this was great to find out that the relay was not the issue.It’s compact, reliable, and has already paid for itself by helping me confirm a bad relay without wasting money replacing good ones. Definitely useful for DIYers or even pros who want a quick way to verify relays.

This is an easy to use compact relay tester that shines for automotive use. It has handy spring loaded alligator style connectors to adhere to your battery positive and ground connections, and the relay ports on the face of the unit allow for insertion of automotive 4 and 5 pin relays.The ability to actually physically test relays for proper functionality is excellent, as it allows for proper diagnosis and troubleshooting of electrical issues, versus throwing the "parts cannon" at the problem and replacing things unnecessarily. The connectors are long enough (about three feet) so that you'll be able to connect to your battery in the car or on your test bench and you can test away at your leisure.Another great feature about this tester is how compact and light weight it is - easy to throw in your tool bag or keep in your glovebox or map pocket in the door without taking up much space.All that said, if you're looking for a way to diagnose common automotive electrical issues and test out your relays, this would be a great tool to do it with, as it can assist in solving basic problems and save you money over the long run.

never expect so fast shipping and great quality product! Will buy again! very satisfied!

Yes, I can confirm it works, with both good and bad relays. Or rather, it identifies which are good and which are bad. That's all you needed to know, but, I have some modification tips below if you keep reading.It's pretty simple, shove a questionable relay into the matching socket, toggle the 4 vs. 5 pin button up or down, and hit the test button. It will cycle through turning the relay on and off automatically, and tell you whether it's good (green) or bad (red).I was tired of hooking gator clips up to relays manually and I was going to DIY one of these using some spade connectors, or an old fuse box, to quickly eliminate whether the relay is the problem or not. For the cost of this thing, I'll save myself the hour.I'll bring this with me to the junkyard (and a tiny 12v alarm battery or a 9v battery) to test out relays before I buy them.The enclosure isn't that durable, it's pretty flimsy plastic, so it shouldn't go loose in the toolbox with wrenches and crowbars, but, other than that it's a great little unit.At first I was lamenting that it doesn't come with a little onboard 12v battery, to avoid needing the battery clips, but then I realized that it determines its power source (12v vs. 24v) by what you connect it to. I never work on 24v systems, so I'll probably buy some random dollarstore 9v device for a buck and hotwire a little 9v battery and an on/off switch to it, epoxy that to the back of this tester and clip and get rid of the battery clamps. A 9v is plenty to turn on/off a 12v relay. Then there's no worries about tangling or ripping the wires in the toolbox.

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We needed to test a relay on an older car and didn’t have a tester in the garage. When I saw this one, I decided to order it to give it a try. It worked great and got the job done!The relay tester arrives in a small cardboard box. Inside the box is the tester with the 12V battery cables hardwired into it. You also get a small instruction booklet to get started. The unit is light and fairly basic from a quality standpoint, but it does the work when testing relays.We first tried it with a relay we already knew was bad. You start by inserting the relay into whatever slot fits the pin pattern of the one you have, and then press the button to switch between 4-pin or 5-pin. Then, you connect the battery cables to a 12V battery and the test will begin automatically. If you get red, it means you either don’t have a relay plugged in, or the one you have is faulty. If you press the test button it will perform the test again in case you suspect something wasn’t connected right the first time.We then tried the relay we weren’t sure about. It started clicking and the test light flashed green several times until settling on solid green. This confirmed that the relay was still good and we even repeated the test using the test button and it worked again. This gave us the answer we needed quickly.Overall, I’m really happy with this relay tester as it works really well. You have to have a 12V battery handy for it to work but since this is an automotive relay tester, they assume you have one around or on the vehicle itself. If you’re looking for a basic really tester that’s good value, I can definitely recommend it!

I picked up this relay tester to make diagnosing electrical issues a little easier, and it's been a useful addition to my toolbox. It was simple to hook up using the battery clips, and testing both 4-pin and 5-pin relays was quick without having to guess whether a relay was good or bad. The results were easy to understand, which saved me time compared to swapping relays around or checking them manually with a multimeter. The tester feels lightweight but solid enough for regular DIY use. The only downside is that you'll still need to know if your relay is compatible with the tester, as it won't work with every relay style. Overall, it's a handy diagnostic tool that has already helped me troubleshoot automotive electrical problems more efficiently.

While it's not a tool I use often, this is a nice time save when testing relays that you suspect may be defective, or testing some you may have in a storage box to determine if you should keep or discard them. It also provides a quick and sure determination of the relay and whether it is working or not which saves any guess work. It's convenient, easy to use and reliable. It works with both 4 and 5 pin styles, 12 or 24 volt relays and uses a simple red/green LED to indicate the status of your relay (flashing green 10 times=good, red=bad). For use you simply connect the alligator clips to a 12 or 24 volt power source as needed for the relay you are testing, set the 4/5 pin button and press the test button to get an instant result.The quality looks and feels great and it should provide good use for a long time. It's very reasonably priced and I would recommend this tester if you find yourself needing something like this.

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Its a really handy tool to have in your toolbox for quick relay testing. The build feels good quality, the aligator clips are tight & there is enough cable to reach across the engine bay. It tests all the most common 12v & 24v automotive relays easily. It cycles the relay 10 times and displays a green for pass & red for fail.It fits all the relays in my truck & car's fuse box, but any relay that has a skirt (typical standalone relays) for a pigtail plug, will not fit for obvious reasons.Overall it works as it should, is simple to operate and is super quick vs a multimeter and test clips.

This Automotive Relay Tester is easy to use, connects to 12V battery, has an indicator light and fits 4 or 5 pin Relays.No issues testing some Relays out from my F150 Truck which it runs through tests making a clicking noise then illuminates a green light once completed if no problems found.Automotive Relay Tester that is reliable, portable and runs various tests on Automotive Relays.

This relay tester looks exactly as pictured and it works well. The tester is quick and easy to use as it can be attached to a car battery and all I need to do is press the test button. Previously I would use a 12v power supply with alligator clips and my multimeter to check for continuity which is somewhat time consuming.The tester feels durable for shop use and it's primarily made of a rigid plastic and the battery clips have strong spring tension. The LED is easy to see while under bright shop lights or under direct sunlight. Overall this is a helpful tool for testing relays and I like that it automatically detects if a relay is normally open or normally closed.

Car relays control many vital functions in our modern vehicles. While they rarely fail, when they do, they can render a car undrivable. Replacing them can be costly, so it's smart to verify that a relay malfunction is the cause, and to identify the correct relay to replace. That’s where the OBDResource RT911 12V/24V automotive relay tester comes in handy! Connecting it to the battery near the fuse box under the hood allows a driver to test any relay right on the spot. In some cases, if there are identical relays, a driver could swap a less critical relay to reach home or a nearby service center.This exact situation happened to me a few years ago when the Hi-Beam relay in my car failed, forcing me to drive over 100 km on low beams. My car had four identical relays; I could have swapped the faulty one with the rear defog relay to get home safely if I had this device handy!This tester is very easy to use, compatible with both 12 and 24V electrical systems, and can test 4 or 5-pin relays. After connecting it to the battery, select the appropriate slot, set the pin button according to the number of pins, and press the test button. Green is good, red means bad, simple!I now keep this small tester in my backseat organizer, right next to my multimeter. I hope I won’t need it, but if and when I do, I’ll be prepared! This is a 5-star product!

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I was excited to get my hands on a relay tester, which would certainly make troubleshooting easier. Traditionally, we troubleshoot a potential relay issue by substitution or elimination. A device that you could quickly test a relay with, is a heck of an idea.On the surface, this seems to be the ticket. Select 4 or 5 pin relay with the selector button, hook it to a battery, stick the relay in the matching slot, and push the test button. Easy.And it does do that- to SOME relays.Looking at my picture, you can see two types of standard 12v 5 pin automotive relay. Notice the one with the skirt around the terminals? Yeah- you can't test those. Unfortunately, the skirted relays are VERY common in automotive and marine electrical systems. They lock into the socket for mounting, waterproofing, or both.This relay tester has a flat surface with recessed terminal slots. As such, you cannot insert a skirted relay, making the device useless on some very common relays.If the manufacturer were to redesign this with raised pedestals that the skirts could fit around, this tool could be a home run.Something that isn't clear to me, and important- if you watch my video clip, I test a standard 5-pin relay. Clearly, the device is pulsing power to pins 85&85, triggering the relay, and the green LED is flashing in sync. I presume this is indicating continuity between pins 30 and 87 (normally open) but what makes a 5 pin relay different than a 4 pin relay is terminal 87A- normally closed. There really is nothing on the device or instructions that indicate to me if there is indeed continuity between pins 30 and 87A when the relay is in a closed, at-rest state.Getting back briefly to the 4-pin/5-pin selector button- this really should be a slide or toggle switch. It's state is somewhat ambiguous in use.I implore the manufacturer to address these things, and caution buyers about the potential pitfalls to this device.

Simple and easy to use. Saves time and money.

A simple and easy way to be able to diagnose a faulty relay. Plop your relay into the corresponding position on the tester and select where it is a 4 or 5 pin relay. Hit the test button and it listen to the relay cycle through. Once the test is complete the bulb will indicate either Green or Red to indicate the relay condition. I used this to test a Horn relay on a vehicle to diag where the issue lies. I can say that the relay passed no issues. Helped me find out quicker opposed to using a DVOM with alligator clips.

Very easy to work with. Plug it on battery, put relay in it, choose the number of pins of the relay you put on it and press test...My car seemed to work great (old 2010). Still bought this cause I like to do what I can on a car (change lights, add windshield washer and some other little things).So I tested my relays and one was testing red (which means it was bad, still working as I had no problem but still bad). I don't know for what part it was (I just took the relays, plug them in the machine one by one and put them back). Maybe the bad relay was for the brake lights... I tried changing them last spring with leds and they didn't work).Nice little machine to have for something very easy to do to help your car stay in order.Excellent buy.

It works well and fast diagnosis, but to confirm the relay is functional and be confident i still load test the relay with a 10 amp load light.

It works great glad to have purchased this item. It's going to help me in a lot of ways. I'm so Excited 🤪🫶🏼💋

Proper tester to do 4,and 5 pin. More expensive than previous one and DOES NOT HAVE A CASE.Would have made product perfect

I’ve been using this automotive relay tester for a short time, and it’s already become a handy tool in my garage. If you’ve ever dealt with a faulty relay, you know the usual method is swapping relays around until you figure out which one is bad. That can be frustrating or impossible if you don’t have a spare. This tester makes it simple.It works with both 12V and 24V systems, and you can switch between 4-pin and 5-pin relays with the click of a button. Using it is straightforward: connect it to your battery, plug in the relay, select the pin type, and press test. The device instantly shows a green light for good or a red light for bad, eliminating guesswork.I mostly use it for 12V systems, but having the ability to test 24V relays is a nice bonus. Overall, it’s a simple, effective, and reliable tool that saves time and helps with diagnosing electrical issues at home. Definitely worth having if you work on vehicles or quads regularly.