XOR at 12V and a few amps.

[Jamie]

Jim Thompson wrote:

On Sat, 29 Sep 2012 13:27:12 -0700, Jim Thompson



On Sat, 29 Sep 2012 14:16:54 -0500, John Fields


[snip]


Since Toyota's have been described as "5-wire", I presume that's...

Brake Left Brake Right
Turn Left Turn Right
Ground

So each side is independent and "Turn" (flashing) trumps "Brake"
(steady).

...Jim Thompson

---
Mine works like that and provides hazard mode flash as well, with
three relays instead of four:


. +12
.BRAKE---+ |
. | O K1
. [COIL]. . ./
. | O->/ <-O
. GND | NC |
. | |
. | +----|--[LLAMP]--+
.LFLASH>-+ | | | |
. | | O K2 | GND
. [COIL].|. . .\ |
. | O-> \<-O
. GND | NO |
. | |
. | +----|--[RLAMP]--+
.RFLASH>-+ | | | |
. | | O K3 | GND
. [COIL].|. . .\ |
. | O-> \<-O
. GND NO


Are both "Brake" lamp circuits wired together? I have a wiring
diagram for my Q45... I guess I should open the manual and see how
Infiniti does it.

...Jim Thompson

Booboos. We fret over brake and turn, but what about tail/running
lights?

...Jim Thompson

---
There's no requirement for them to be included.

Around her, in Arizona-land, you're required to have at least one
"running" light or a "flag" ;-)

I'm wondering if "5-wire" isn't actually...

Running
Brake
Left Turn
Right Turn
Ground

...Jim Thompson


I found this...

http://tinyurl.com/44m6pmu

...Jim Thompson

Right, something I stated way back at the start of this tread and I
took that from memory.

So, it is true then, if it's on the internet it must be true
otherwise beware of information coming elsewhere.

Jamie

---
Do neither of you have a clue?

The OP asked for steady brake lights when the brake pedal was pressed,
unless a directional signal was invoked, at which time the directional
signal would override the brake signal and flash the directional lamp
on that channel.

You are absolutely lost...

YOu really know how to screw up things.

Jamie

 

[Jasen Betts]

What about four way (hazard) flasher mode?

I'm working on the assumption that the "4 wire trailer plug"
is ground, left brake, right brake, tail lights.

 

[Jasen Betts]

Mine works like that and provides hazard mode flash as well, with
three relays instead of four:


. +12
.BRAKE---+ |
. | O K1
. [COIL]. . ./
. | O->/ <-O
. GND | NC |
. | |
. | +----|--[LLAMP]--+
.LFLASH>-+ | | | |
. | | O K2 | GND
. [COIL].|. . .\ |
. | O-> \<-O
. GND | NO |
. | |
. | +----|--[RLAMP]--+
.RFLASH>-+ | | | |
. | | O K3 | GND
. [COIL].|. . .\ |
. | O-> \<-O
. GND NO

yeah but you need to run a (at-least) a 12V wire from the fusebox to the trailer
hitch. mine can be patched into the existing harness at the rear of
the vehicle,

If you're going to run a 12V wire you can do it with 2 relays.
(probably not going to work if the vehicle has LED signal lights)

.. 12V
.. |
.. | +------[RLAMP]--+
.. RFLASH>-+ | | |
.. | | O K1 GND
.. [COIL].|. . .\
.. | O-> \<-o
.. | | NO
.. BRAKE---+ |
.. | | +------[LLAMP]--+
.. | | | |
.. | | O K2 GND
.. [COIL].|. . .\
.. | O-> \<-O
.. | NO
.. LFLASH>-+

 

[Jamie]

Mine works like that and provides hazard mode flash as well, with
three relays instead of four:


. +12
.BRAKE---+ |
. | O K1
. [COIL]. . ./
. | O->/ <-O
. GND | NC |
. | |
. | +----|--[LLAMP]--+
.LFLASH>-+ | | | |
. | | O K2 | GND
. [COIL].|. . .\ |
. | O-> \<-O
. GND | NO |
. | |
. | +----|--[RLAMP]--+
.RFLASH>-+ | | | |
. | | O K3 | GND
. [COIL].|. . .\ |
. | O-> \<-O
. GND NO


yeah but you need to run a (at-least) a 12V wire from the fusebox to the trailer
hitch. mine can be patched into the existing harness at the rear of
the vehicle,

If you're going to run a 12V wire you can do it with 2 relays.
(probably not going to work if the vehicle has LED signal lights)

. 12V
. |
. | +------[RLAMP]--+
. RFLASH>-+ | | |
. | | O K1 GND
. [COIL].|. . .\
. | O-> \<-o
. | | NO
. BRAKE---+ |
. | | +------[LLAMP]--+
. | | | |
. | | O K2 GND
. [COIL].|. . .\
. | O-> \<-O
. | NO
. LFLASH>-+

Or coil current much less than normal bulb current.

...Jim Thompson

Vehicle supplied circuit!

Jamie

 

[Jasen Betts]

If you're going to run a 12V wire you can do it with 2 relays.
(probably not going to work if the vehicle has LED signal lights)

. 12V
. |
. | +------[RLAMP]--+
. RFLASH>-+ | | |
. | | O K1 GND
. [COIL].|. . .\
. | O-> \<-o
. | | NO
. BRAKE---+ |
. | | +------[LLAMP]--+
. | | | |
. | | O K2 GND
. [COIL].|. . .\
. | O-> \<-O
. | NO
. LFLASH>-+

No, you just need a pull-downs. The exisitng indicator and brake lamps
are typically 15W lamps which have a hot resistance less than 15 ohms
(and cold resistance even lower) but yeah, if both brake lamps, or
both indicator lamps on one side fail it'll stop working. If LED lamps
are used it's game over.

 

[Jasen Betts]

. +12
.BRAKE---+ |
. | O K1
. [COIL]. . ./
. | O->/ <-O
. GND | NC |
. | |
. | +----|--[LLAMP]--+
.LFLASH>-+ | | | |
. | | O K2 | GND
. [COIL].|. . .\ |
. | O-> \<-O
. GND | NO |
. | |
. | +----|--[RLAMP]--+
.RFLASH>-+ | | | |
. | | O K3 | GND
. [COIL].|. . .\ |
. | O-> \<-O
. GND NO

yeah but you need to run a (at-least) a 12V wire from the fusebox to the trailer
hitch. mine can be patched into the existing harness at the rear of
the vehicle,

Since you're working on the assumption that the "4 wire trailer plug"
is ground, left brake, right brake, and tail lights, then the tail
light hots could be the 12V input to K1.

Over here tail lights can be turned off (and usually are).

 

[Jasen Betts]

---
Really?

Where would you connect them and what value of resistance would you
use?

I'd use the existing indicator and brake lamps already installed in
the vehicle. At 12 ohms each the resistance is sgnificanly less than
the 90 ohm resistance of a typical automotive horn relay.

worst case is the hazard blinkers running both relays in parallel into
the only the two brake lights.

in all other cases you two "pulldowns" per relay.

.. .--(RF)--.
.. |--(RR)--|
.. | |
.. --+-- | 12V

. | |
. | | +------[RLAMP]--+
. RFLASH>-+ | | |
. | | O K1 GND
. [COIL].|. . .\
. | O-> \<-o
. | | NO
. BRAKE---+ |

.. | |
.. .--(LB)--+ |
.. |--(RB)--+ |
.. | | |
.. --+-- | |

. | | +------[LLAMP]--+
. | | | |
. | | O K2 GND
. [COIL].|. . .\
. | O-> \<-O
. | NO
. LFLASH>-+

.. |
.. .--(LF)---+
.. +--(LR)---'
.. |
.. --+--

 

[petrus bitbyter]

---
Really?

Where would you connect them and what value of resistance would you
use?

I'd use the existing indicator and brake lamps already installed in
the vehicle. At 12 ohms each the resistance is sgnificanly less than
the 90 ohm resistance of a typical automotive horn relay.

worst case is the hazard blinkers running both relays in parallel into
the only the two brake lights.

in all other cases you two "pulldowns" per relay.

. .--(RF)--.
. |--(RR)--|
. | |
. --+-- | 12V

. | |
. | | +------[RLAMP]--+
. RFLASH>-+ | | |
. | | O K1 GND
. [COIL].|. . .\
. | O-> \<-o
. | | NO
. BRAKE---+ |

. | |
. .--(LB)--+ |
. |--(RB)--+ |
. | | |
. --+-- | |

. | | +------[LLAMP]--+
. | | | |
. | | O K2 GND
. [COIL].|. . .\
. | O-> \<-O
. | NO
. LFLASH>-+

. |
. .--(LF)---+
. +--(LR)---'
. |
. --+--

Well, I think it'll work. I did not check your calculations as I suppose
you're fully capable to do the math correct.

I also consider it only interesting as an academic solution and that was
what the OP asked for.

As a real world solution I consider it bad engineering practice. Too much
changings in the original installation making it less reliable. Things like
pull ups/pull downs are common in the world of electronics but not in an
automotive lighting installation. Failing of the extra joints, the extra
resistors and even original bulbs do not only effect the trailer lights but
also the cars lighting.

Another practical point that did not get attention was the place of the
adaption circuit. Somehow the four wire plug of the trailer does not fit
into the five wire outlet of the car. Best practice is leaving the car
unchanged. But then you have to mount a five wire plug and cable to the
trailer. Once you are that far it may be easier to mount new five wire
lamps on the trailer.

petrus bitbyter

 

[Jasen Betts]

If you're going to run a 12V wire you can do it with 2 relays.
(probably not going to work if the vehicle has LED signal lights)


---
I see a problems in that the input switches must be form C.


No, you just need a pull-downs.

---
Really?

Where would you connect them and what value of resistance would you
use?

I'd use the existing indicator and brake lamps already installed in
the vehicle. At 12 ohms each the resistance is sgnificanly less than
the 90 ohm resistance of a typical automotive horn relay.

worst case is the hazard blinkers running both relays in parallel into
the only the two brake lights.

in all other cases you two "pulldowns" per relay.

. .--(RF)--.
. |--(RR)--|
. | |
. --+-- | 12V

. | |
. | | +------[RLAMP]--+
. RFLASH>-+ | | |
. | | O K1 GND
. [COIL].|. . .\
. | O-> \<-o
. | | NO
. BRAKE---+ |

. | |
. .--(LB)--+ |
. |--(RB)--+ |
. | | |
. --+-- | |

. | | +------[LLAMP]--+
. | | | |
. | | O K2 GND
. [COIL].|. . .\
. | O-> \<-O
. | NO
. LFLASH>-+

. |
. .--(LF)---+
. +--(LR)---'
. |
. --+--

Well, I think it'll work. I did not check your calculations as I suppose
you're fully capable to do the math correct.

I also consider it only interesting as an academic solution and that was
what the OP asked for.

it was a just for fun question, the OP already has an off-the-shelf
solution.

As a real world solution I consider it bad engineering practice. Too much
changings in the original installation making it less reliable.

Adding a single wire is too much for me, too many interior panels,
membranes and other automotive hardware to mess with, (not so bad in a
Kombi, where the wire just has to cross the engine compartment, but OP
had a Toyota)

Things like
pull ups/pull downs are common in the world of electronics but not in an
automotive lighting installation.

Failing of the extra joints, the extra
resistors and even original bulbs do not only effect the trailer lights but
also the cars lighting.

none of the existing wiring need be cut, the only thing that needs to
be added is the relays, the 12V supply wire, the trailer socket, and
the cable to it.

Another practical point that did not get attention was the place of the
adaption circuit. Somehow the four wire plug of the trailer does not fit
into the five wire outlet of the car. Best practice is leaving the car
unchanged. But then you have to mount a five wire plug and cable to the
trailer. Once you are that far it may be easier to mount new five wire
lamps on the trailer.

You could add an extra socket. OTOH the 4 relay circuit I proposed way back
would work in-line with an exisiting "5-wire" socket. you could stick
it in a project box and attach it to the trailer with velcro straps
when needed.