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Author Topic: 98 Palomino Mustang Electrical 8 pin to 7 blade  (Read 97 times)

mdbushnell

  • Posts: 2
98 Palomino Mustang Electrical 8 pin to 7 blade
« on: June 29, 2020, 12:08:00 PM »
Hello All,
I am new to the popup camper world. Growing up my parents had a truck camper and later a pull trailer and I never had to worry about if things worked or not. But now, being an adult with my own family I need some help. We have used tents until recently buying an old popup which needed some work.
I have completed most of the canvas work and now replaced the roof with a new rubber cover and am doing the electrical. I am pretty good with wiring things up when standard wires are available. But with this PU it has a 8 pin rectangular hookup so I cut the wires and started converting it to a 7 blade adapter since my GMC has a 7 blade receptacle.
I think I have it figured out as far as running lights, turn signals, brake lights and so forth.
The wires are from top left to right
Blue 14 G (Trailer brakes - which this trailer does not have) - Green 14 G (Running lights) - Black 14 G (Pig tailed - one to trailer one to PU battery positive terminal and 12v + for interior lights) - White 12 gauge (Battery Negative terminal)
The second row of wires from left to right are
White 14 G (To PU chassis ground) - Brown 14 G (right turn) - Red 14 G (Left turn) - Grey 14 G (Unknown where to connect this to).

If you see something wrong with the wiring please reach out and let me know so I do not fry anything.

So here are my questions...
1. Out of the 8 wires there were 2 white ground wires. One for the PU frame ground and one for the PU battery ground terminal. But which one is which? Maybe since going to a 7 blade I just hook them both to the same ground and then pigtail them to their respective locations?
2. There is a gray wire and I have no idea where this is supposed to go on the 7 blade connector. I think it is for keeping the refrigerator cool when travelling, but where would I hook it to on the 7 blade adapter?
3. What wire do I hook to the PU battery positive post so that it gets charged while travelling?
4. How do I switch from shore power to battery power so the interior lights and fridge work from the battery?
5. This sort of ties to question #4 in that if the battery does not power the fridge is the propane supposed to and if so is there a manual which shows me how to get that system working? (Gas stove and fridge?) I have not tried anything thus far with the gas as I do not want to blow myself or the trailer up.
6. The PU has a fresh water tank, but not a drain tank as far as I can tell. So in the sink, it has a drain, where does the drain go to or does it just run outside? No bathroom so its not that kind of water.

I hope that someone can help us out here with these and thank you in advance. Hoping to take it camping for the 4th of July this coming weekend.
Sincerely, Matt

Rene T

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Re: 98 Palomino Mustang Electrical 8 pin to 7 blade
« Reply #1 on: June 29, 2020, 12:24:15 PM »
Welcome to the forum.
This may get you started in the right direction.

https://www.ajtnt.com/Info/7-Way-Diagram
Rene, Lucille & co-pilot Buddy
AKA  Pep N Mem
2011 Chevy Duramax 2500 HD 4X4
2011 Montana High Country 343RL
From the Granite State of NH
& Florida Snowbird in Lakeland FL

Mark_K5LXP

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  • 2005 Itasca Sunova
Re: 98 Palomino Mustang Electrical 8 pin to 7 blade
« Reply #2 on: June 29, 2020, 12:34:42 PM »
Quote
with this PU it has a 8 pin rectangular hookup
So is that factory or something someone just added later?
Quote
1. Out of the 8 wires there were 2 white ground wires. One for the PU frame ground and one for the PU battery ground terminal.
Seems unusual there'd be two separate ground connections unless maybe the one at the battery frame ground was a larger conductor for high current?  Just a guess.  For the purposes of your trailer connection I would only use one connected to nearby frame ground.  The minute you start playing with separate grounds you're asking for weird problems.
Quote
2. There is a gray wire and I have no idea where this is supposed to go on the 7 blade connector.
It's not a color that's used with anything I've seen before.  Maybe check for voltage and see if there is any when doing different things with the vehicle.
Quote
3. What wire do I hook to the PU battery positive post so that it gets charged while travelling?
The 7-blade has provision for battery hot, see the diagram here:

https://bendtrailers.com/trailer-wiring-guide/

Quote
4. How do I switch from shore power to battery power so the interior lights and fridge work from the battery?
You normally don't have to switch anything.  The converter charges the battery and operates the devices when you're plugged in, when you're unplugged the battery takes over.
Quote
5. This sort of ties to question #4 in that if the battery does not power the fridge is the propane supposed to and if so is there a manual which shows me how to get that system working? (Gas stove and fridge?) I have not tried anything thus far with the gas as I do not want to blow myself or the trailer up.
That is entirely make and model depenent.  Find out what you have there and dig up the manuals on the intertubes.
Quote
6. ...So in the sink, it has a drain, where does the drain go to or does it just run outside?
My popup sink went to a garden hose fitting on the side of the trailer.  Had a cap on it to keep critters and dirt out.  If you took the cap off the drain water would just run down the side onto the ground.  To keep from making a muddy mess next to the popup I used a short "reel jumper" hose from the box store and let it drain into a 3.5 gallon bucket with a lid.  My fresh water tank wasn't much more than that and you really don't use that sink much anyway, so it was never more than one trip into the woods to dump it on the way home.

Mark B.
Albuquerque, NM

Rene T

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Re: 98 Palomino Mustang Electrical 8 pin to 7 blade
« Reply #3 on: June 29, 2020, 12:55:16 PM »

6. The PU has a fresh water tank, but not a drain tank as far as I can tell. So in the sink, it has a drain, where does the drain go to or does it just run outside? No bathroom so its not that kind of water.

As someone said, it probably  drains to a out side hose fitting. Mine was right on the side of the pop up adjacent to the sinks and it was labeled. Now just so you know the majority of the states do not allow you to just dump it on the ground. Get a short length of hose and stick it in a bucket then bring it to a dump station. Ask the campground when you make reservations.
Rene, Lucille & co-pilot Buddy
AKA  Pep N Mem
2011 Chevy Duramax 2500 HD 4X4
2011 Montana High Country 343RL
From the Granite State of NH
& Florida Snowbird in Lakeland FL

mdbushnell

  • Posts: 2
Re: 98 Palomino Mustang Electrical 8 pin to 7 blade
« Reply #4 on: June 29, 2020, 04:04:04 PM »
So is that factory or something someone just added later?Seems unusual there'd be two separate ground connections unless maybe the one at the battery frame ground was a larger conductor for high current?  Just a guess.  For the purposes of your trailer connection I would only use one connected to nearby frame ground.  The minute you start playing with separate grounds you're asking for weird problems.It's not a color that's used with anything I've seen before.  Maybe check for voltage and see if there is any when doing different things with the vehicle.The 7-blade has provision for battery hot, see the diagram here:

https://bendtrailers.com/trailer-wiring-guide/
You normally don't have to switch anything.  The converter charges the battery and operates the devices when you're plugged in, when you're unplugged the battery takes over.That is entirely make and model depenent.  Find out what you have there and dig up the manuals on the intertubes.My popup sink went to a garden hose fitting on the side of the trailer.  Had a cap on it to keep critters and dirt out.  If you took the cap off the drain water would just run down the side onto the ground.  To keep from making a muddy mess next to the popup I used a short "reel jumper" hose from the box store and let it drain into a 3.5 gallon bucket with a lid.  My fresh water tank wasn't much more than that and you really don't use that sink much anyway, so it was never more than one trip into the woods to dump it on the way home.

Mark B.
Albuquerque, NM

Thanks to all for the responses.
It is the factory plug. Rectangular 8 pin. I think I got everything wired except for the gray wire. I read somewhere that it was for the fridge while traveling to keep it cooled.
I am testing it out this evening and will get back to you all.
I have not been able to verify this so if anyone knows for sure would be great.