How to Check Relays on Automobiles

Video Transcript

"This is the relay center in the car. They'll be in various locations on vehicles. Some even have them inside, some even in the trunk. And if you have a defective relay there are relay checkers, most technicians obviously have these. And what you can do is remove, if I can get one of these out right here, wiggle it out. Yep here it is, here's the relay right here. Again, you can remove them and you can actually ohm them out to pinpoint checks, you can check for power at certain points. Another good way to check them if you don't have any special tools to substitute a relay, take an known good one out just exchange it for a minute and see if it corrects the concern or the issue that you're having. That's another good way. But if we look at the cover right here, as it goes on and when I pull it's right in this corner right here so that's fan number one. So if you have a fan and it doesn't come on, the engine is running hot, that would indicate possibly this would be a good place to go to check this relay and make sure it's working. Of course you want to make sure the relay circuits also fused, that that's working good. Again, this can be checked. You don't want to just randomly replace it because somebody told you that you have a bad relay. You need to prove that it is indeed defective."