Trailer wiring

Please can any one help me!! Im so discussed with this. I have a 1998 chevy
malibu car. I put on a hitch and wiring harness. Everything works but the running lights. I have day time running lights on the car. I know this should be simple but I've tried just about everything. Thanks for the input. Penguin82

 

Normally on American cars there are four wires for the trailer. They commonly are color coded on trailer harnesses... Green for Right turn signal... Yellow for left turn signal... Brown for tail and running lights... White for ground... If you are having trouble with the running lights.. they are supposed to come on with the tail lights of your car. The brake lights are powered through the turn signal circuit... does that answer your question?

 

I have the turn signals working ..I did have brake lights..But now after messing with it like everyone said..I now have running lights BUT NOT brake lights..I can get all but one thing to work...If I hook up the brake wire to the brown running lights..the 3rd brake light on my car is on all the time. So...Do I need an adapter for that last wire?????

 

First off... forget the third brake light... that is of no use for trailer lighting... The brake lights are on the same circuit as the turn signal lights... when you step on the brakes... it sends power to both turn signal filaments... but the turn signal switch on the steering column disconnects the brake light on the side the signal is set to... and connects it to the flasher circuit. But both the brake and turn signals use the same filament in the bulb. The tail and running lights are on a seperate circuit. You really only need to connect the turn signal wires (yellow for left) (Green for right) and Brown for the tail lights... The tail lights and running lights are on the same circuit. You should run a seperate ground wire (white) so that the ground circuit isn't completed through the ball and hitch.

 

Tell me... do you have a twin filament bulb for tail lights?... or do you have seperate brake, turn, and tail lights like european cars have?

 

I think he has a split bulb arrangement and requires an adapter. A small device that gets some two sided tape applied and stuck in the trunk, near where the wire hookup is. The instructions on the package will solve your problem. This was a common problem on imported cars for some time, but has been resolved by this cheap little gadget. The auto parts store can help you quickly, they've seen this problem before or you can find it on the shelf in the trailer parts isle.

 

Most American cars have the dual filament bulbs... but I'm not that familiar with his particular model. A trailer adapter is available at most RV supply stores and costs about $15.00... They have a diode block inside that allows the "five wire" European and Japanese electrical systems to work with the "four wire" American trailer lighting.

 

Most American cars now use the 5 wire systems (separate, single filament bulbs) and have for some time. They also use metric fasteners on just about everything. With the exception of lug nuts, wheel rim diameters and a very few other items near all on American cars and trucks are metric.

This has been caused by a number of reasons. The American manufactures now own large percentages of the overseas manufactures if not out right. It was quickly noted that the fasteners were much cheaper to produce there and the market world wide for metric so . . . Standardization and out jobbing have had a big role to play as well.

 

Interesting... I wasn't aware that American cars had gone to the single filament wiring like the rest of the world. The last American car I rewired was a 1957 Thunderbird. I've wired several trailer connections for foreign SUV's and installed the adapters. I was well aware that most American cars were now metric. I must be a dinosaur because I have a lot more "inch" tools than metric. But Offshore boats in America are all still built with inch hardware. I wired a trailer for a 2001 Chevrolet Dually... but the truck already had the trailer lighting hook-up and may have had the adapter fitted from the factory.

 

With the advent of the separate turn lens, the wiring needed to be separated as the bulbs were. It was very common to have the 1157/2057 style bulbs in turn/brake lamp assemblies, but now the styling has favored multiple lens, mostly having an amber turn and ruby brake/run. This necessitated the change.

The application of the single wire setup is easy enough to ID and some cars/trucks still have them (a lot more trucks then cars). If the car/truck has a brake light that goes off and then flashes when the brake is pressed and the turn or flasher is on then it's the old style. If the brake light stays on during the operation of the turn or flasher, it's separate signal wires.

I have to admit, in a dense fog the amber turn is seen farther then the ruby and is a logical choice, but the American manufactures haven't been accused of being logical very often. I'm glad they are sometimes inspired.

 

I gotta know... did the addition of a separate ground wire solve the problem?

I can't count the number of times its done the trick for me.