How to wire the reverse lockout solenoid on brake actuater?

Sprung Monkey

Well-Known Member
#1
How to wire the reverse lockout solenoid on brake actuater?



Been researching this wiring and am unsure about the existing trailer electrical connecter it’s a round type that came from GM. It has a lid and a but plug inserted in it.



?4.do I use the but plug to connect the trailers lights?



Not sure if this coupler even has a reverse wire?


I've allways had the 4 pin flat type of coupler



?1.anyone know the color codes associated w/ this round GM electrical coupler?



I believe this one wire coming from the tie down actuater soleniod needs +12V DC.



?2.doe’s my GM round plug have a reverse connection?



?3.or will I have to run a separate wire to behind the tail light to connect to the reverse white backup light?



Thanks
 

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Sprung Monkey

Well-Known Member
#3
heres the but plug pigtail so its the center terminal? I assume GM w/ there infinite wisedom refers to reverse as auxcily.
thanks
 

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djthumper

Administrator
#6
heres the but plug pigtail so its the center terminal? I assume GM w/ there infinite wisedom refers to reverse as auxcily.
thanks
If this is a picture of your harness you are missing the actual plug. This is what you should be seeing.
012.jpg
 
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Sprung Monkey

Well-Known Member
#7
The 4 pin plug won't have the reverse lock out seliniod

when I backup a incline the surge actuater will slide forward enguaging the brakes.

yes that is the plug I have attached to the hitch had to get on all fours to plug or unplug now I see how it's keyed.

yes I have the pig tail I posted a image of it.
 
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Sprung Monkey

Well-Known Member
#9
trailer has 4 wires now add one for the actuater so 5 total. I assume the actuater grounds itself when bolted to trailer frame.
Thanks SM
 

djthumper

Administrator
#10
If it were my trailer it would be swapped for a 7 wire, so it is properly set up.

Please use spell check, it can be hard to read your posts with a lot of misspelling.
 
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Sprung Monkey

Well-Known Member
#11
Diffuaculty wiring 7 way



It got late and dark quick yesterday, wasn’t able to get much done on trailers 7 pin coupler I was able to get the right side blicker working period.



?1.since I’m able to see the right blicker working doe’s this mean that the rust on my hitchs ball isn’t interfering w/ ground connection from 97x to trailers frame?



I have green and lighter green on pass. Tail light , side so I still I haven’t found the taillights taillight or blicker. When I reverse this connection w/ other green I get no blicker or taillight.

Edit: I do have continuity from front to back of trailer pass. Side wire.

It’s use’s a normal color code of yellow being blicker and brown being taillight. My next couple steps will be establish continuity for front/ to back driverside trailer wire.



Then observe the location on the driver tail lights brown wire this is tail lights so now I can find the pass. Side blicker wire.





Here’s what I’ve connected all from trailer end

pos1- ground

pos7 trailer antireverse lockout.

Pos3 tail light

?2.I assume pos3 actualley has two wires pass.driver taillights both normalley brown?



Pos5 right turn green. I got confussed her I thought I could wire each circuit indidualley like I either connect blicker or I connect tail/ or brake light however when I reversed the working right blicker then the taillight wouldn’t come on.

Any tips
 
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Sprung Monkey

Well-Known Member
#12
I can only manage to get the brake lights /blickers to work the tail lights will not come on.

Attach image of how I have it connected. Plus I ground white wire’s at trailer end and at each lights end.



I assume I’m not getting a connection from the OEM 7 pin plug.

Maybe I could remove taillight then tap into the taillights wire for a source?
 

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#13
Did you confirm you have power at the trailer parking light fuse, or that the fuse isn't blown?
 
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Sprung Monkey

Well-Known Member
#14
I haven't confirmed any power at 7 pin coupler I did turn on the headlights to auto and observed yellow fronts and red tails on 97x .

the upper center tailight won't lightup like the brakes/blinkers do.
fuse #16
Vehicle Center High-Mounted Stoplamp (CHMSL)


Maybe I could remove taillight then tap into the taillights wire for a source?
 
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Sprung Monkey

Well-Known Member
#16
gonna check the plug for signal w/ taillights and headlights turn on w/ DVM, even though I get no signal now.

there is a none functional red tail/stoplight mounted on the middle of upper roof I refer to as a center.

another observation the LED light flashs very quickly compared to the second regular bulb I don't think having two differnt type lights would effect the none taillight issue.

will check all fuse's plus remove a couple like air suspension/onstar/rear climate control/ect.
Maybe I could remove taillight then tap into the taillights wire for a source?

edit: I inspected the rear hatch orange/black wires and they where in godd condition I will reinforce w/ some excellent 3M electrical tape the gromenet is a tad diffacult to reattach.
 
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#17
I wouldn't tap into the regular taillights as you have an existing trailer wiring. It might be broken somewhere between the rear fuse box and the plug.

The center light is a Center High Mount Stop Light. Check the fuse for that as well. It works independently of the other brake lights with its own fuse.

Check for power on both sides of the fuse posts.

Adding a tap to the regular taillights will introduce extra load that the circuit may not be able to handle. I don't recommend it. It's not like the old days where wires had extra meat on them to handle an extra load. Nowadays they are able to handle just the existing load, if that even. OEMs have become cheap and use the smallest wire possible.
 
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Sprung Monkey

Well-Known Member
#18
I wouldn't tap into the regular taillights as you have an existing trailer wiring. It might be broken somewhere between the rear fuse box and the plug.
what doe's trailer fuse control?the whole plugs 12VDC remember I have brake/glinkers working fine.



Check for power on both sides of the fuse posts. this must be at the mega fuse?
.
yes you make alot of sense to not insert additional loads to an already designed circuit.

hopefully it's a blown fuse I will buzz out each, that would be easy.
underhood there's fuse #32 for Trailer and under seat #42 Trailer Park


fuse#50/51 UH fuse block are for trailer turn signals.which work fine.

I don't intend to use rear wiper because I]ve read it sometimes hangs up incorrectly on it's perch and creates a battery drain I would like to pull the wiper fuse #9

I bet fuse #16 Vehicle Center High-Mounted Stoplamp is blown.


worst case scenario would be run a I assume rear taillight wire from rear fuse block #42 to the plugs terminal #3 tail lights.I will trace voltage



I could be viewing the plug backwardwards like my pin #1 is actually pin#6 and my pin#3 is actually pin#4 and 2/5 7 stays the center. this is actually one combonation I haven't attempted yet..
 

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#19
The 30A trailer fuse is for the post for the red wire. More info here:
Red Wire (The disconnected ring connector near battery/underhood fuse box)

You don't need that red wire connected. It's only to supply 12V+ constant battery to the trailer.

The diagram for the trailer plug is right on the cover.

I don't understand why you are adding the rear wiper to this???

This is what I meant with testing the fuses on both posts, but I think you already know this:
 
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Sprung Monkey

Well-Known Member
#20
I tested all the fuses under the seat and they are all good.and yes I used you'r method of using the two posts of the fuse I actually only did a continuity test on all the fuses under seat, none under hood, still no taillights.

crawled under saw the bundle of taillight wiring entering the car from pass. side then it's mostly under the carpet.

I believe the trailer end plug location #3 for taillights connects to a thicker blue wire. is faulty the taillights must be on another circuit than the brake/turn signal?


attach image of how I have wired Trailer end maybe its backward however this is the only way to wire to have at least brake/turn signal
I was just saying I'm not planning to use rear wiper. and wanted to remove it's fuse. since I'm working on the fuse block.
 

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Sprung Monkey

Well-Known Member
#21
Brakes lights/blinkers work Can’t get tail-lights to come on

I have a 07 trailblazer it has a 7 pin round trailer plug I have the male end at the trailer.

I’ve managed to get the brake lights and blinkers working however the tails won’t come on.
I have checked all fuses under the hood and under the rear seat all have continunity.

I inspected the wiring under the car and they appear fine I don’t want to rip the carpeting and rear seat out to trace a wire.

Been informed that I can’t tap into the cars taillight wire because it would overload the circuit.

I have wasted way to much time messing w/ the none tail light issue.

I sometime trailer in the dark so it would be good to have sometype of red light back there.
All I can resort to w/ this car is battery operated taillights.unless anyone has usefull advice.
Thanks
 
#22
I have checked all fuses under the hood and under the rear seat all have continunity.
But did you confirm power at the trailer parking light fuse, when the tail lights of the truck are turned on? If you have power at the fuse, but not at the plug, then you know the problem is somewhere between there. If you don't want to trace everything under the carpet, at least probe the wiring entering the trailer connector. Just to rule out that last connection.

Alternative measures: You could tap into the tail light harness, just use that signal to trigger a relay, and run power from the stud of the rear fuse block, with an inline fuse. Possibly less work, use an Add-a-fuse off the trailer parking light fuse slot, and run a new line back to the trailer connector, effectively bypassing that troublesome wire altogether.
 
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Sprung Monkey

Well-Known Member
#23
But did you confirm power at the trailer parking light fuse, when the tail lights of the truck are turned on? If you have power at the fuse, but not at the plug, then you know the problem is somewhere between there. If you don't want to trace everything under the carpet, at least probe the wiring entering the trailer connector. Just to rule out that last connection.

Alternative measures: You could tap into the tail light harness, just use that signal to trigger a relay, and run power from the stud of the rear fuse block, with an inline fuse. Possibly less work, use an Add-a-fuse off the trailer parking light fuse slot, and run a new line back to the trailer connector, effectively bypassing that troublesome wire altogether.
excellent advice
I have no voltage on #4 w/ headlights on. either in front or back of coupler.

also checked the big red wire again no voltage.

I do have continuity on white wire to cars frame.

I think #42 Trailer Park fuse under rear seat could be tail-lights?
thanks
 
#24
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Sprung Monkey

Well-Known Member
#25
I will inspect trailer fuse #42,w/ lights on/off will check voltage on this circuit.

you suggested earlier a adapter how will an adapter 7 to 4 help there's no power at pin #4?

new plan B glue 12" 12VDC red LEDs stripes on stern for taillights powered w/ boat battery will also get amber LED stripe for side markers.

both glued to hull I think the aft. LEDs will add enough light for night fishing/netting.