Towing RV Tips: Verifying Tow Charge

First thing you want to do when you're coupling a vehicle up to a trailer, or a new trailer especially. You want to verify that the towing vehicle, that everything works on the towing vehicle. So the first thing we're going to do is, I'm going to have Dave just turn on the running lights and you can see by the tail lights, we've got running lights. I'm going to have him tap his brakes. We've got brakes. We're going to check the reverse. We've got reverse lights. Now he's going to turn his running lights off and turn on his 4-Ways. Which should be the same as his turn signal. So hit your flashers? Okay. So at that point, we've got everything on the towing vehicle does appear to be working. So now what we can do is, we could quickly attach the umbilical cord or the hitch plug to the vehicle and then go around and check the lights. Or if you do find you have a problem that's a little tough to test the circuits here once you install the connector. So once it's in there, you're kind of forced. Any testing we want to do now, if we had a failure on the camper, we would have to go to the individual lights on it. But in the event you had all your lights working, you plugged the umbilical cord into the trailer hitch connector, and you had a light out. There's a connection in the vehicle from this point to this point. So at that point, you would want to go in and test each of the circuits. Now on this particular cover on the trailer hitch connector it's got a little diagram. There also diagrams you can pull offline that show the different configurations. This happens to be a 7-Way RV or trailer. That means it's got seven connectors. It's got a brake connector or a brake signal in it. It's got left, it's got right, it's got reverse. And it's got a battery charged circuit that would go right to the onboard battery on your towed vehicle. So what you could do, in the event you plug your connector up to the vehicle and you had one or no functions working. The first thing you'd want to do is to make sure you've got the 12 volt signal coming out of here. So it's quite easy to do. You've got a diagram here. You've got a diagram that you could follow here. So, what I'm going to do now is we're just going to simulate that. We don't have anything working on the trailer. So we'll go ahead. And I'm going to have Dave turn on his 4-Ways. You want to make sure you have a good ground. So now we see his four ways are flashing. So I should have a left terminal that should be flashing and I should have a right terminal. So if I come over here, there's my left terminal, there's my right terminal. So I know that it's coming out of the vehicle. Now that was my failure on the trailer that I did not have brakes or left or right turn signal and I've got it here. I know then that I have a problem at this point or further back through the coach, underneath the wires. You know, there's a cable that runs underneath the frame that could be damaged. A lot of times, it's just in the tail lamp sockets or a pretty weak connection back there. So at that point, we know our turn signals are good at the tow vehicle. Now I'm going to have him push on the brake. And that should be the same two wires. Okay. Let off the brake. Now go ahead and put it in reverse and always be careful when somebody is.. You're behind the vehicle in reverse, you don't want to get caught. So now we're going to find the reverse which should be right there. Okay. Take it out. So now we know the reverse is good. Now go ahead and just do your running lights. Shut them off. Turn them on again? Off? Okay. So we know he's running lights are good. So we've checked the left turn signal, the right turn signal, the running light. We've got the power going, that will go back to the battery. That's for the breakaway out here or that that's what would give your battery, keep your battery charged while you're going down the road. That's through this circuit right here. So at this point, everything in this connector is good. Again, if it wasn't, if we were missing one of those or any of those functions, it's back at the vehicle. There could be a fuse underneath the dash, underneath the hood. You would have to verify that first. So now that we're good here, the next thing we would be doing, we'd make the connection. And now at this point, we have to go to the back of the unit and we'll check all the functions in the rear of the trailer. Okay. We've got the towing vehicle hooked up to the trailer. So now what I'm going to do is, we're going to test all the light functions to see if everything's working correctly. We're going to start with the clearance lights. And.. Dave you want to turn on the clearance lights? Okay. So now what we're doing is, we're going to inspect the clearance lights on the side and they're good on this side. Looks like they're good across the top, good across the bottom, and this side looks good. So, shut off the clearance lights? Go ahead and turn on your 4-Ways? Okay. So we can see we've got a problem with this light right here on the left side. That would be his brake signal. His left turn, his right. But we'll go ahead and demonstrate it with.. Go ahead and turn on your right turn signal? Now the left? Now go ahead and tap your brakes? So we know we've got a problem here, both with it'd be the brake left turn and 4-Way. Go ahead and put it in reverse? I don't know if this has a reverse lamp in it. Doesn't look like it does. Okay. It does not. So we won't get a reverse light back here. Okay. That's good. So now go ahead and leave your 4-Way on. Now, the first thing we're going to do, everything looked like it was good except for this lamp right here, the tail light. This happens to be a snap in. So we're going to pop the lens cover off. I want to go careful. Some of these have been out in the weather for quite a while and they get a little brittle. So we're going to pop that out and we can see that this bulb we're just barely in there. Now, sometimes you're going to find that there's going to be some green corrosion on the end of the bulb. And you can take a little steel wool, a little Scotch-Brite, check your socket inside. A lot of these lamps have a weep hole in the bottom. And it looks like even though on this one, it does. Looks like that lens cover was made for a reverse light. There's no reverse light in this fixture, but you always.. If it has a weep hole, you want to make sure if you're pulling lights off, that you get the left, the hole should always be in the bottom. This one does not have a hole. It's just got a little gap in the side. So check your connections. This has two wire ground, a lot of these old, some of the less expensive trailer lights would just use the ground that would go through a screw, very poor connection. This does have two wire ground or two wires, positive and ground. So we'll just.. The light on this looks good. It was just loose in the socket. So we'll just put it in, lock it in, make sure it's good. Wiggle it around. Doesn't look like there's any problem. Go ahead and turn off the 4-Ways and just touch your brakes? Now do the running lights? And so that's all it was. Was just a loose bulb. But again it could have been a connection. That's good! Could have been a loose connection, a bad bulb. And you can.. Sometimes a bad bulb will give itself away. You'll see a little discoloration or a dark, darker spot on the glass. But, this case it was just connections. Then you can snap the thing back in. We can check it one more time. Go ahead and hit the 4-Ways? Left turn? Left turn? Okay. So, running lights? Good! So at this point, we've got all the lights on the trailer work, the sidewall lights work, or the clearance lights work on the side. Now there's one more item on here, on this trailer that it has that you should also check. And that's called a breakaway. This unit does have a breakaway on it. And if you ever wanted to test that, it would just be a matter of raising one tire off the ground, have your towing vehicle hooked to it or make sure that the onboard battery is charged and then release the pin and the brakes should lock up. And with that, we've tested all the lighting on the trailer and everything seems to be working fine on this unit.