NA my car electical ugh

tonycondon

tonycondon

Gastons CRO (Chief Dinner Reservation Officer)
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Tony
Well I hooked up trailer lights to my car. Interesting things have been happening since. My car has a single bulb with two filaments for the brakes. lets say filament 1 is the steady running light and 2 is the brake light. The trailer has a single filament with increased voltage for the brake. So when I connected the wire harness for the trailer to the car, I hooked wires for filaments 1 and 2 to the single wire for brakes on the trailer. Now, during the day, with daytime running lights on, when I hit the brakes, my dash lights (radio and mileage displays) dim. Not a big deal really but slightly annoying. I suspect this is because the filament 1 (which is also connected to the dash lights) and filament 2 really are connected now. At night, this does not happen as the dash lights are dimmed anyway, however, for some reason my cruise control does not work at night!? How the heck are these interrelated?

Also, initially I had the right blinker hooked up for the trailer wiring. It seemed simple enough, but caused major headaches. It would start out fine but once I started moving, the right blinker would start acting like a brake light, dim but steady on all the time and brighter when braking. what the heck? Im positive I have the right wires hooked up and have so far wrote that up to a short between the right blinker wire and the brake lights on the trailer. It did blow a fuse on my car at night which was aton of fun, no steady brake lights or dash lights driving down the highway.

Anyone got any Ideas on how to better wire the brake lights so that I dont have the dim issues during the day. And any thoughts on the cruise control? that seems just bizzare...
 
Tony:

You need to use the proper lights for the trailer; very easy to get basic tail lamps with 1157 (or equivalent) bulbs, similar to the ones in the car's tail lights.

When you connected the brake lamp circuit to the tail lamp circuit (which, in effect, you have done), you made sure neither could work correctly.

Brakes on, applies 12v back through tail lamp circuit, in turn triggers night(lamps on) dimming logic for dash displays.

Likewise, tail lamps on at night, feeds 12v back through the brake lamp circuit, fools cruise control brake cutoff circuit into thinking the brakes are on all the time, hence, will never engage.

Undo this mess!

And keep your paws off of Toby's Cherokee!
 
thanks spike, that makes sense. perhaps it will clear up the mess i have with the right blinker too, though i doubt it. looks like i get to rewire the trailer, woohoo!
 
thanks spike, 25 feet isnt long enough but ill look for something like that when i get back to ames this weekend.
 
Something to be cognizant of: when you install the "heavy-duty" flasher, you'll see a very slight delay before your turn signal lights illuminate. The H-D flasher actually works "opposite" (to keep it simple and brief--past my bedtime, and I'm turning into a pumpkin as we speak) the way a normal flasher does.

Also, make certain the trailor's ground is carried through the connector to the car's ground.

Best of luck.

Jim
 
tonycondon said:
thanks spike, that makes sense. perhaps it will clear up the mess i have with the right blinker too, though i doubt it. looks like i get to rewire the trailer, woohoo!
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Stop by Radio Shack and pick up a few zener diodes. Those are like electrical check valves. They will pass the juice in only one direction.

You need to figure out which way to flip the ends. Put it in the circuit from the car brake light to the trailer lights. When the tralier lights work leave it that way. With the diode the wrong way the trailer lighhts will not light.

Do the same with the night running lights. The diode should be installed oriented the same way.

No more feedback loop. No more dash lights coming on.

I suspect that RV suppliers have modules for doing the wiring which have the diodes inside.
 
Mike,
they going to have something like that for 12V? Most of the stuff I find about them on wikipedia mention much lower voltages.
 
tonycondon said:
something like this?
http://cgi.ebay.com/1N5242B-ZENER-DIODE-12-VOLT-5-WATT-NOS-5ea_W0QQitemZ7547399103QQihZ017QQcategoryZ4666QQssPageNameZWD1VQQrdZ1QQcmdZViewItem

im probably going to be stopping at the local radio supply shop on the way home from work. might not have what i need, but im hoping for an old gray hair behind the counter who can point me in the right direction
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Tony (sigh).

Just wire up proper trailer lights, properly.

Don't go trying to use electronics-grade diodes to jimmy-up your trailer lights.

Just wire up proper trailer lights, properly.

Diodes won't change the fact that, if you have only one filament in the bulb, you'll get no difference from the 12v supplied for tail lamps, and the 12v supplied for turn/brake.

The difference in brightness comes from differently-rated bulbs /filaments, not different voltage.

Just wire up proper trailer lights, properly.

Did I mention, that you should...
 
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SCCutler said:
Did I mention, that you should...
Click to expand...

put a diode between each connection? :rofl:
OK fine ill do it right, I thought you were a lawyer or something, whered you get all this electricity knowledge?

for your hotshot dual filament trailer light system, is it going to still have a flat 4 connector or am i going to have to redo the car end too?
 
nah i kinda prefer lots of electrical/duct tape, a hope and a prayer, extra fuses and lots of luck. Isnt that how all electrical things work?
 
tonycondon said:
nah i kinda prefer lots of electrical/duct tape, a hope and a prayer, extra fuses and lots of luck. Isnt that how all electrical things work?
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maybe that's how ya'll do it in iowa...

For example. With your electrical/duct/cheap ass radioshack diodes..you would have a couple'a problems. You are holding your brakes at a stop light and have your turn signal on.. Guess what... People behind you don't know that cause the light is already lit up.

You are driving at night. You start to slow down. BOOM you get rear ended..Why did that happen? Because your rear lights were already lit up..Ya need bulbs with two filaments.
 
ya, its interesting cause the way it is wired now, the trailer lights work, and they get brighter when i hit the brakes. I just have issues on the car end as layed out in first post. and of course no right blinker as its disconnected.
 
tonycondon said:
put a diode between each connection? :rofl:
OK fine ill do it right, I thought you were a lawyer or something, whered you get all this electricity knowledge?

for your hotshot dual filament trailer light system, is it going to still have a flat 4 connector or am i going to have to redo the car end too?
Click to expand...
Listen to Spike, although I was waiting for Lance to pipe up and say a Zener diode wouldn't do it.

I used to make house light dimmers with those. Put a doide in series with the light fixture and it cuts off half of the sine wave so you get half brightness. You add a toggle switch to short out the diode so you have ON-OFF & FULL-HALF brightness.

I *think* I got diodes that had a 200v rating.

That would make a good JA project.
 
larry, its a 99 Olds Alero. tail light setup is a single bulb with two filaments, seperate turn signal. When i bought my wiring adapter, it was supposed to be for my car, i think.
 
1.) Follow the wiring directions for the trailer wiring kit without trying to overthink it.

2.) Go to OReilly's or AutoZone or whatever and get a plug-in trailier light kit for your specific make/model of car. They have them now that simply plug into the wiring harness that is running your car lights. No splicing necessary!

3.) Voila! Trailer lights that don't blink left when you're turning right and don't turn on your radio when you roll down the window. :D

-Chris
 
Yup.

You did not tell us that you had the separate turn signals; you have, then, four (4) hot circuits to deal with (tail, brake, left signal and right signal), and (of course) the ground.


There are adapters available for your application, pretty reasonable in cost. I like Larry's "go to U-Haul" advice- it's true, they have a lot of stuff tailored for the broad market of trailer-towing neanderthals. 'Course, that ain't you, right?
 
mikea said:
Stop by Radio Shack and pick up a few zener diodes. Those are like electrical check valves. They will pass the juice in only one direction.

You need to figure out which way to flip the ends. Put it in the circuit from the car brake light to the trailer lights. When the tralier lights work leave it that way. With the diode the wrong way the trailer lighhts will not light.

Do the same with the night running lights. The diode should be installed oriented the same way.

No more feedback loop. No more dash lights coming on.

I suspect that RV suppliers have modules for doing the wiring which have the diodes inside.
Click to expand...
Naw. First Zener diodes are intended to avalance at a specific reverse voltage, something that's clearly not needed here. Second, no trailer should be wired so that the same filament serves both brake/turn and tail functions. Most use a common one for brake and turn as do many American cars/trucks.

Tony, if you truly have trailer lights with only one filament per side they are only useable as tail lights or brake/turn signals, not both. If you want/need both, either add a separate tailight (you only need one in most states for a short trailer, and for a long trailer you probably need side lights too), or replace the lights you have with dual filament ones.

I'm also wondering if your trailer actually has the correct (dual contact) lampholders and someone just put the wrong bulb in. Take a look at the socket and see if there are two contact points (and two wires from each socket) at the bottom of the socket. If so it's meant for a dual filament (brake/turn + tail) lamp. There are single filament two contact lamps but they are for boats not trailers. Another clue would be the slots in the sockets for the bayonet pins on the lamp(s). A combo (brake/turn + tail) socket will have one slot lower than the other to prevent you from installing the wrong bulb type or putting the correct one in the wrong way, but it's usually pretty easy to "overide" this with some excessive force.

And if you have the correct two filament bulbs in a dual contact socket, you can still have either or both of two problems. One is if your tow vehicle has separate circuits for turn and stop, like virtually all foreign made cars and trucks do plus many contemporary domestic ones. In that case you need to add a "converter" which you can get from most any auto parts store. It connects to the 3 separate wires for left, right, and brake and combines them into two (leftturn/brake plus righturn/brake). The tail circuit may also run through the converter, but that's just a straight through connection for convenience. All these devices supply power to the respective trailer light when either the turn or brake light is on but not both. That way the trailer lamp lights when you hit the brakes and flashes with the turn signal whether you are on the brakes or not. When you have the turn signal blinking and the brakes on, the trailer light will follow the opposite of the turn signal (on when off and vice versa). The computer/electronic geeks call this "exclusive-or" operation.

The second common problem is the lack of a good connection between the trailer frame and the car's frame (ground). Hitches typically make a poor connection once a little corrosion builds up inside the coupler and/or on the ball. The cure is to make sure there is a wire connecting the two frames together. Typically this is a white wire and for some reason the makers of trailer wiring harnesses often make that wire about 6 inches long which generally results in a broken wire on one or both sides of the connector fairly soon after you start using the trailer. For a quick check to see if this is part of your problem clamp one jumper cable to a bare piece of metal on the trailer and on the car and check the lights for correct operation.

BTW, you could easily take a prewired trailer light harness and extend it with some three conductor ribbon wire. I think you can find that at most auto parts stores along with some crimp connectors to splice it.
 
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ok fiddled around more tonight. there ARE two filaments in the trailer. so i unhooked my goofed up attempt at getting brake lights that was causing problems, then hooked up both blinkers. I had tail lights, and both blinkers working, then tried to figure out how to get brake lights. I thought "hook the blinker wires (to trailer) to the cars brake wires" sounded like a good idea and voila! the brakes worked, woohoo! then turned blinker on, and got one blink and fuse blew. replaced fuse, unhooked my new way to get brake lights and reread lances post :) so looks like i need to get a converter so that is the project for tommorrow.
 
...gettin' there, Antonio!

===

By the way, in answer to the earlier question, I was always a car-guy, and my first career was as a tech-type guy, first carrying a toolbag and fixing microfilm equipment (Bell & Howell, made in Lincolnwood, Illinois and better than anything the Japanese ever thought of building), then asa tech support / product engineering guy on COM (Computer Output on Microfilm) systems, in Irvine, CA.

So, in the process of all that, I learned how to make things work, and how to effectively route electrons to their appointed destination without letting any magic smoke escape.
 
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