[atakacs]

I tried to wire my TA for my trailer but I'm stuck. I wired the ground, tail lights, left and right turn signals correctly but I have no idea where to attach the wire for the brakes. On my TA the turn signals and brakes are the same light... just both on constantly instead of one blinking (except for the wing light). Right now, I have tail (running) lights and proper turn signals when not braking but I have no brake lights on my trailer and if I try to turn on a turn signal while braking, the trailer flashes the opposite signal. Do I have to run a wire all the way up to connect to my spoiler's brake light? Can anyone help me out?

<5 wires to vehicle [Draw-tite Module] to trailer & 4-pin attachment>

Thanks,

Andre

This post has been edited by atakacs: Sep 25 2007, 05:31 AM

[sgarnett]

I'm surprised that an 02 would have shared turn signal and brake lights. I thought everything from 97 up had separate amber turn signals. Four-wire trailers do use the same bulb for both.

If you wire an older vehicle with combination lights to a trailer with combination lights, they should flash together (in phase).

If you wire a newer vehicle with separate lights to a trailer with combination lights, you need to use a converter. The brakes should of course work together, and the turn signals should flash together, but with brakes AND turn signals, they will flash out of phase.

The brake converter contains a very simple logic circuit to combine the separate brake and turn signals into a combined signal. The boolean equation is LIGHT = BRAKE xor TURN. Exclusive OR (xor) means that one and only one can be true. So, if the turn signal blinks on while the brakes are already on (or vice versa), the conditions are no longer exclusive, so the light turns off. In an older vehicle with combined lights, that equation is already implemented by relays or whatever on the vehicle, so you don't need the converter. Four-wire trailer wiring is a holdover from the past, when combined lights were the norm.

Also, my stock flasher couldn't handle the extra load from the trailer. If I disconnected the trailer, the signals seemed to be correct at the connector (using a multimeter or LED trailer light tester), but it started acting screwy witht he trailer pugged in.

The timing circuit in the stock flasher is sensitive to the total load of the bulbs, and that's intentional. When one bulb is burned out, the flashing (and clicking) changes, so you know to check the bulbs. Attaching a trailer increases the load current beyond the range that the flasher was designed for.

The auto parts store had two kinds of heavy duty flasher, a thermal version designed to handle more current than stock, and an "electronic" version. The thermal version worked OK with the trailer, but didn't work without the trailer. The electronic version has a timing circuit that is independent of the load current, so it flashes at the same rate with or without the trailer. That's what I have now. The only downside is that you won't know a bulb has burned out until somebody tells you unless you check them periodically.

This post has been edited by sgarnett: Sep 25 2007, 01:18 PM