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Vikings
08-07-2007, 02:27 PM
I just noticed that when my brake is depressed AND turn signal is on my trailer lights act like a 4 way blinking with the side that I'm suppossed to turn being much dimmer. In other words, both trailer lights go on when the brake is depressed (truck brake only on my rig), which is good But, when I turn a signal light on as well, both lights blink like I have the 4 ways on and the side turning, say I have the left blinker on, is much dimmer.

Before this I would just sit in the truck and say is my lights working and do signals and whatever but this is the first time I actually walked back and looked myself, lol. ****ers!

Good thing you can still see my truck lights I guess but could this problem be caused my me not hooking up the ground?

btw, the trailer is brand new and high quality and I also bought a brand new electrical hook up for between the trailer and truck. The truck is a 92 chevy.

Bill Kapaun
08-07-2007, 03:00 PM
"...but could this problem be caused my me not hooking up the ground?"

Assuming you have 2-1 bulbs like an 1157-
Both filaments have their 12V feed and go to ground. End of story-
BUT IF the ground isn't connected, the 12V goes into 1 filament (brake/signal) and then passes into the other filament (taillight) at their common ground point in the "same" bulb, which then feeds the other taillight, since taillights (& marker lights) are on the same circuit.
EDIT to add-
When hitting the brakes, you are probably also turning on the taillights, but simply can't see it. IF you have side markers, see if they come on when you hit the brakes.

LarryF
08-07-2007, 03:08 PM
btw, the trailer is brand new and high quality and I also bought a brand new electrical hook up for between the trailer and truck. The truck is a 92 chevy.

If its a brand new and high quality trailer, it sounds like the guy who did the hook up didn't do it correctly. But that may not necessarily be the case. Over the years I've spent many hours trouble shooting trailer wiring, so I know how irritating it can be trying to isolate a problem. At this point, you don't really know if its the wiring in the truck or the trailer that is causing the malfunction. If I were in your shoes, before I did anything else, I'd hook up the trailer to a truck I knew had correct wiring for its trailer-hitch jack in order to eliminate one from consideration. Good luck with it!

Vikings
08-07-2007, 10:15 PM
I do have two trucks, both with brand new connectors. I'll give that a try.

fixer67
08-07-2007, 11:08 PM
"Good thing you can still see my truck lights I guess but could this problem be caused my me not hooking up the ground?"

Trying to use the hitch ball as a ground path is not a good idea. First, the path is poor and can fail and any time. When it fails a new path maybe found by the power back flowing into other systems. Like you hit the brakes and the running light on the truck may come on or some such thing. And here is one most people never think about. Running the ground though the hitch ball causes arcing. This will pit the plating on cause the hitch ball to rust which will shorten it life. When I do trailer wiring work I do not let the truck and trailer touch.

Vikings
08-08-2007, 03:24 AM
"Good thing you can still see my truck lights I guess but could this problem be caused my me not hooking up the ground?"

Trying to use the hitch ball as a ground path is not a good idea. First, the path is poor and can fail and any time. When it fails a new path maybe found by the power back flowing into other systems. Like you hit the brakes and the running light on the truck may come on or some such thing. And here is one most people never think about. Running the ground though the hitch ball causes arcing. This will pit the plating on cause the hitch ball to rust which will shorten it life. When I do trailer wiring work I do not let the truck and trailer touch.

The ground on the connector thing was a islet, I didn't know where to screw it to. I believe it's just hanging there, I thought I would have to drill a hole in the frame of the truck or something. And on my second truck, a Ford Ranger with a 4.0 6cyl. I don't think there is a ground. That's actually the truck I used to pick up the trailer with. The guys there, that made the trailer, made sure my lights were working. But I use the Chevy 8 cycl. on everyday use. I think that's the one that had a loose ground connection that I didn't know what to do with.

LarryF
08-08-2007, 07:35 AM
The ground on the connector thing was a islet, I didn't know where to screw it to. I believe it's just hanging there, I thought I would have to drill a hole in the frame of the truck or something. And on my second truck, a Ford Ranger with a 4.0 6cyl. I don't think there is a ground. That's actually the truck I used to pick up the trailer with. The guys there, that made the trailer, made sure my lights were working. But I use the Chevy 8 cycl. on everyday use. I think that's the one that had a loose ground connection that I didn't know what to do with.

My Ford pickup is a 150. I bought it new and it came with the trailer-hitch wiring properly grounded. I suspect your Ranger is likewise, and that must be why everything was ok when you picked up the trailer. It sounds like you might have found your problem if the ground wire is just hanging there. drill a hole and secure it to the truck frame with a screw. If you want to check it first, use a clip lead to temporarily secure it to the frame to see if that eliminates the problem. I expect it will and then screw the dangling wire to the frame.

thecrankshaft
08-08-2007, 01:24 PM
Replace both the trailer light bulbs.

fixer67
08-09-2007, 10:55 PM
Replace both the trailer light bulbs.

I have seen people put (it is hard to do but it can be done) 1156 bulbs in sockets made for 1157 bulbs and vice a versa. Make sure all the bulbs are the right ones for you set up.

Vikings
08-09-2007, 11:01 PM
You guys must mean AFTER I hook that ground up?

fixer67
08-09-2007, 11:17 PM
You guys must mean AFTER I hook that ground up? Well, YES.

Fix the ground FIRST.