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CHenige Tue Feb 13, 2018 8:16 pm

cbeck wrote: Looking at the 1st schematic. Shouldn't the trailer lite harness be connect to the tailites on the tailite side of diode to prevent back flow up wire 18 towards front lites? ps, nice legible drawing :D

I read the directions that signal will only flow left to right. And the signals on left are kept separate.

Will hopefully find out tomorrow from etrailer.

Dale M. Tue Feb 13, 2018 8:24 pm

CHenige wrote: cbeck wrote: I saw a key phrase on a earlier post, do the head and tail lites turn on with the same switch at the same time ie can you turn on only running lites without turning on headlites?

I think I used some incorrect terminology. One set of front lights are regular halogen front headlamp bulbs. The other single light is a long LED lamp that will be used as a bright. No running lights.

One switch controls the front halogen headlamps and taillights. The other switch controls the LED bar as brights.

thanks

You have a problem with diode to tail/marker lights.... You are getting a backfeed from tail lamp circuit of towing vehicle through bad/defective/miswired diode that is illuminating headlights .... Pull the wire off diode (anode) going towards "headlight" switch, (far left switch in diagram), and problem will go away....

Do you have volt-ohm meter, and do you know how to test diodes?

Dale

Yennek Tue Feb 13, 2018 9:42 pm

CHenige wrote: cbeck wrote: Looking at the 1st schematic. Shouldn't the trailer lite harness be connect to the tailites on the tailite side of diode to prevent back flow up wire 18 towards front lites? ps, nice legible drawing :D

I read the directions that signal will only flow left to right. And the signals on left are kept separate.

Will hopefully find out tomorrow from etrailer.

Are you actually using an e-trailer part? If so, what part?

However, if you are just using some diodes, you are right and wrong. Per your diagram in the first post, the diodes only let the electricity flow from left to right through them. So as drawn, your trailer harness will feed to the left, completely avoiding the diode to power the headlights, and will feed to the right through the diodes to power the tail lights. Now if you move the trailer harness after the diodes, it will feed to the right, completely avoiding the diodes to power the tail lights, and the diode will stop it from feeding right to left and keep the headlights off.

cbeck Wed Feb 14, 2018 4:19 am

And a kiss solution could be to put the tail/head lites onto a off/on/on switch isolating the lites from each other until both on positions is selected similar to a oem headlite switch.

CHenige Wed Feb 14, 2018 2:27 pm

OK, I confirmed with etrailer that my wiring is correct.

I remembered I had an extra unit and used my circuit tester.
(+) red probe (-) black probe

there is open between the 2 ins
there is open between either in (+) and out (-)
there is closed between out (+) and either in (-)
Above makes sense and should work with how I have it wired.

took out the one in the vehicle.
there is closed between the 2 ins - unit is defective.

There is melted plastic on one of the ins. I have no idea why it would melt. There is a 20 amp fuse in the fuse box for this headlamp circuit and 10 gauge wire for the headlamp wiring. 18 gauge for the trailer/diode/rear lights which are now all LEDs. And a 5 amp fuse just past the diode to protect.

All I can think is I had a short at one time and the diode could not take it.

Put the other diode in and will watch and see what happens.

thanks for all the input!



Dale M. Wed Feb 14, 2018 3:57 pm

E-trailer site says diode are good for 85 amps.... Something really when wrong or it was defective from the start...

Dale

cbeck Wed Feb 14, 2018 4:31 pm

Here is the way I read this schematic.
1-12vdc+ is coming from trailer connector, thru a 18 ga wire labeled #19 to the left side of diode.
2 12 vdc goes left to right thru a fuse, down wire 8-20? To the tail lites.
3 -the 18 ga wire from the switch goes to the same side of the diode as wire 19, after that 18 ga wire splits off on a 10 ga wire #16 that feeds the front lites.
4-there is no diode between the trailer plug and the front lites.
5-the diode only stops stray current coming from the tail lites.
6-you need another diode or switch to isolate the front lites because the current flows left to right thru the diode but there is nothing to stop 12vdc from making a left turn BEFORE the diode and flowing to front lites and switch.

Hey dale, does this call for your electrical schematic symbols legend again? I almost peed on myself when I started looking closer at that.

Dale M. Wed Feb 14, 2018 6:23 pm

cbeck wrote: Here is the way I read this schematic.
1-12vdc+ is coming from trailer connector, thru a 18 ga wire labeled #19 to the left side of diode.
2 12 vdc goes left to right thru a fuse, down wire 8-20? To the tail lites.
3 -the 18 ga wire from the switch goes to the same side of the diode as wire 19, after that 18 ga wire splits off on a 10 ga wire #16 that feeds the front lites.
4-there is no diode between the trailer plug and the front lites.
5-the diode only stops stray current coming from the tail lites.
6-you need another diode or switch to isolate the front lites because the current flows left to right thru the diode but there is nothing to stop 12vdc from making a left turn BEFORE the diode and flowing to front lites and switch.

Hey dale, does this call for your electrical schematic symbols legend again? I almost peed on myself when I started looking closer at that.

But there is..... It seems its defective by CHenige's latest discovery/post...

One has to understand that this diode pack has two isolated inputs (anodes) and one output (cathode)

https://www.etrailer.com/Accessories-and-Parts/Roadmaster/RM-792.html

Dale

CHenige Wed Feb 14, 2018 6:27 pm

1-12vdc+ is coming from trailer connector, thru a 18 ga wire labeled #19 to the left side of diode. Yes

2 12 vdc goes left to right thru a fuse, down wire 8-20? To the tail lites. Yes

3 -the 18 ga wire from the switch goes to the same side of the diode as wire 19, after that 18 ga wire splits off on a 10 ga wire #16 that feeds the front lites. both the 10 gauge and 18 gauge wire are connected to the same connector at the switch, so yes

4-there is no diode between the trailer plug and the front lites. There are two diodes in the etrailer unit that keep those two wires independent of each other. So no need for another diode

5-the diode only stops stray current coming from the tail lites. No, see 4 above

6-you need another diode or switch to isolate the front lites because the current flows left to right thru the diode but there is nothing to stop 12vdc from making a left turn BEFORE the diode and flowing to front lites and switch. No, see 4 above

I put together the wiring diagram 2 years ago with the facts above in mind. Issue is something shorted out the diode unit but I thought I had something wrong in my wiring. [/b]

Thought I would show my first diagram from januaty 2016! Come a long ways.
https://www.thesamba.com/vw/gallery/pix/1448762.jpg

Dale M. Wed Feb 14, 2018 6:32 pm

CHenige wrote: 1-12vdc+ is coming from trailer connector, thru a 18 ga wire labeled #19 to the left side of diode. Yes

2 12 vdc goes left to right thru a fuse, down wire 8-20? To the tail lites. Yes

3 -the 18 ga wire from the switch goes to the same side of the diode as wire 19, after that 18 ga wire splits off on a 10 ga wire #16 that feeds the front lites. both the 10 gauge and 18 gauge wire are connected to the same connector at the switch, so yes

4-there is no diode between the trailer plug and the front lites. There are two diodes in the etrailer unit that keep those two wires independent of each other. So no need for another diode

5-the diode only stops stray current coming from the tail lites. No, see 4 above

6-you need another diode or switch to isolate the front lites because the current flows left to right thru the diode but there is nothing to stop 12vdc from making a left turn BEFORE the diode and flowing to front lites and switch. No, see 4 above

I put together the wiring diagram 2 years ago with the facts above in mind. Issue is something shorted out the diode unit but I thought I had something wrong in my wiring. [/b]

Thought I would show my first diagram from januaty 2016! Come a long ways.
https://www.thesamba.com/vw/gallery/pix/1448762.jpg


Yes and I remember the being previous discussion because I was involved in it then...

Dale

cbeck Thu Feb 15, 2018 4:12 am

Huh, dale's link to the gadget appears to be 2 diodes with the -sides tied together before being seald in a housing. Is that right? Holy cow, that could be the 2nd diode I was looking for. I was lead to believe a diode had 1 + input and 1 -output so hopefully you can understand my confusion.
https://www.google.com/search?q=electrical+symbol+...p;ie=UTF-8

Further confusion must come from the diode symbol in the schematic, never seen that one before.
https://www.rapidtables.com/electric/electrical_symbols.html

Pretty schematic, too bad it is not entirely accurate.

Dale M. Thu Feb 15, 2018 8:03 am

cbeck wrote: Huh, dale's link to the gadget appears to be 2 diodes with the -sides tied together before being seald in a housing. Is that right? Holy cow, that could be the 2nd diode I was looking for. I was lead to believe a diode had 1 + input and 1 -output so hopefully you can understand my confusion.
https://www.google.com/search?q=electrical+symbol+...p;ie=UTF-8

Further confusion must come from the diode symbol in the schematic, never seen that one before.
https://www.rapidtables.com/electric/electrical_symbols.html

Pretty schematic, too bad it is not entirely accurate.

Umm....



Dale

CHenige Thu Feb 15, 2018 8:19 am

Yep. Maybe tonight I will put that in my diagram. Thanks for all the input everyone.

Dale M. Thu Feb 15, 2018 8:38 am

CHenige wrote: Yep. Maybe tonight I will put that in my diagram. Thanks for all the input everyone.

Only thing your schematic needs is better definition of LED light bar and halogen headlamps... "Lamp" alone is two broad a definition for us dummy's out here... Other wise its pretty good... But maybe small insert of diode schematic would help ..... You have to remember on other side of screen we don't always know exactly what a vague reference is...

Dale

CHenige Thu Feb 15, 2018 2:36 pm

mba.com/vw/gallery/pix/1746010.jpg[/img]

Dale M. Thu Feb 15, 2018 2:56 pm

Awesome...

Dale



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