my trailer lights still don't work! Help

Hi Guys, Just put a hitch on my Malibu. I think I went to the wrong place! Rack and road in San Carlos. I think they botched my wiring up. Now the trailer lights are going crazy and my center brake light for my car is intermittent. the running lights work fine on the trailer, but the brake and flasher light on trailer are intermittent, could it be the car ground?. Don't know if its the car or trailer. the trailer lights work fine on my four runner. I have a hf trailer. I lost the pm of someone that responded to my last post. Would love to ask for help please. bringing the car back with trailer tomorrow.
Thanks

Ken

If the trailer lights work fine on your 4 Runner, then the wiring in your Malibu is bad.

Most likely a bad ground on the car side.

There is one more thing maybe. At one time when I sold parts. You needed a electronic controller for foreign cars. Something in their wires were not compatible with trailer wiring. So something like that maybe the problem. But with out being there all we can do is guess.     

There is one more thing maybe. At one time when I sold parts. You needed a electronic controller for foreign cars. Something in their wires were not compatible with trailer wiring. So something like that maybe the problem. But with out being there all we can do is guess.   

He drives a Chevy Malibu.

So whom makes the 4 runner? I don't think it is GM. The Malibu may be made in another country using american wire system

The little converter box is used for cars that have amber turn signals. It converts a 5 wire system to a four wire. Should not be the problem here, unless the Malibu has amber turn signals. Sounds like ground issue. Sounds to me like the trailer is trying to ground through the hitch and not the car wiring. Easy way to find out is to take piece of wire and hook to good car ground and run to trailer frame. If it works at tha point fix the car ground to trailer plug wire.

Most likely a bad ground on the car side.

+1

Ken assuming its a 4 wire flat plug if I remember right the white is ground follow it to where it connects to the frame must be clean. It's fine if it wants to ground through the ball as long as that's clean, ground is ground.

Another thing is find out if they changed your flasher unit when they installed stuff. A lot of times a stock flasher can't handle the extra lights and weird shit starts happening.

Without seeing it hard to diagnose.
Get a test light and test the vehicle side wiring at the plug. If everything works as it should there jump power to each of te pins In the trailer connector trailer side.
If all that checks out run a wire from a bolt on the trailer good ground to a solid good ground on your vehicle. Good luck

If none of that solves the problem call a priest cause the mother fucker is possessed.

It's fine if it wants to ground through the ball as long as that's clean, ground is ground.

Not really a good ground. When the hitch bounces in the receiver it loses contact at times and can cause intermittent lighting problems. Seen it happen many times. Add good ground wire and that issue disappears.

Might be more fun than I thought.
If your car is 08 or newer the flash is bcm controlled. With led tail lights led's take a lot less voltage to make work,

Houston we have a problem

Good point there.

If you want to do a DIY Buy older cars pre-computer. 

Just installed a 7 blade rv plug on my truck, lights kept blinking out then just quit working. Turned out to be bad ground inside wire harness.  Added ground right to frame and presto...good solid ground is important for reliability.  Check ground first, then go from there.

They make special flasher units for LED lights IF it is the problem.  My money is still on a bad ground.