Trailer hitch wiring (3 Viewers)

[Hoosier Daddy]

My new-to-me 2010 LC didn't come with the OE tow harness, so I went with the Hopkins harness noted above. I plugged it in on the driver's side.

I wanted the unit mounted in the stock location on the passenger side, so I bought some 7-wire cable (link below) and extended the harness on the Hopkins unit with the help of solder-seal connectors. You need to buy two feet of additional cable.

Trailer Light Cable Wiring Harness 14-7 14 Gauge 7 Wire Jacketed Black | eBay

 

[labcab]

Thanks for this. I’ve had such good luck with etrailer in the past, I just assumed it was the LX. Now it’s wired up and working as expected.

A note on the hopkins adapter...

I just went through resolving a long issue with them. It looks like their adapters are designed to plug in at the junction right before those that are shown in the pic above. This junction is above the exhaust (circled in green in my attachment). It uses the same plugs, but the pins are reversed. So plugging in the Hopkins adapter at the proper location (circled in red) won't have the right pinout.

They ultimately sent me a new harness with the pins reconfigured. Not sure if they are changing the manufacturing of them to the proper pinout. But be aware of this issue.

View attachment 1508978
View attachment 1508977

 

[CalEngineer]

Relatively new to the forum, ended up buying the Hopkins adapter a few days ago and installed on the passenger side (where there’s factory mounting holes 2013 LX). Got the same issue when I went to wire up the trailer. My question is: has anyone rewired it as TeCKis300 suggested? Any idea which wires to cut and splice?

I’d rather go that route than install on the driver’s side

 

[Sandroad]

Relatively new to the forum, ended up buying the Hopkins adapter a few days ago and installed on the passenger side (where there’s factory mounting holes 2013 LX). Got the same issue when I went to wire up the trailer. My question is: has anyone rewired it as TeCKis300 suggested? Any idea which wires to cut and splice?

I’d rather go that route than install on the driver’s side

I bet @TeCKis300 can help!

 

[TeCKis300]

Relatively new to the forum, ended up buying the Hopkins adapter a few days ago and installed on the passenger side (where there’s factory mounting holes 2013 LX). Got the same issue when I went to wire up the trailer. My question is: has anyone rewired it as TeCKis300 suggested? Any idea which wires to cut and splice?

I’d rather go that route than install on the driver’s side

IIRC, the wires are potted in at the receiver side. May be able to switch the pins on the plug size.

Personally, armed with the knowledge on how Hopkins intends one to install this, I would just plug it in at the upstream junction.

Side story, I learned all this the day I went to pickup my Airstream. Spent over 3 hours troubleshooting. I didn't think it was possible that it could be the adapter until process of elimination led me to examining that with the voltmeter. After probing and mapping the pinouts, it was clearly wrong. Cut the entire Hopkins harness, and re-mapped each wire by Macgyver'd with some wire nuts. To say I was irritated was an understatement. Made it home.

 

[Hoosier Daddy]

Relatively new to the forum, ended up buying the Hopkins adapter a few days ago and installed on the passenger side (where there’s factory mounting holes 2013 LX). Got the same issue when I went to wire up the trailer. My question is: has anyone rewired it as TeCKis300 suggested? Any idea which wires to cut and splice?

I’d rather go that route than install on the driver’s side

I plugged mine in on the driver side (where the pins are correct) and then just extended the wires so I could mount the box on the passenger side. Not difficult at all.

 

[CalEngineer]

I plugged mine in on the driver side (where the pins are correct) and then just extended the wires so I could mount the box on the passenger side. Not difficult at all.

Yeah I eventually ended up installing on the drivers side as well - found a slick spot to mount up inside the bumper. Looks like it’ll keep it out of the elements when 4-wheeling. A bit of a pain to plug in, but probably worth the protection. I’ll send a picture next time I’m under it.

 

[kirkagosto]

I just installed the Hopkins adapter on my 2013 LX570. Here is a picture showing wires after they were cut and traced. This is when plugged into the original spot.

 

[RET2]

I just installed the Hopkins adapter on my 2013 LX570. Here is a picture showing wires after they were cut and traced. This is when plugged into the original spot.

View attachment 2579320

View attachment 2579321

Maybe think about some heat shrink wrap coverage?

 

[kirkagosto]

Maybe think about some heat shrink wrap coverage?

The connectors are heat shrink marine connectors. I also added heat shrink to the bundle

 

[RET2]

The connectors are heat shrink marine connectors. I also added heat shrink to the bundle

Sorry didn't see them shrunk

 

[Scylth]

Hey all,

Trying to figure out if i can charge my RV batteries simply by connecting the 7 pin harness to the RV. Testing the 7 pins on the LC with a multimeter, and can’t get a 12v signal with the engine on. Does the LC send aux power through the hitch harness?

 

[RET2]

Hey all,

Trying to figure out if i can charge my RV batteries simply by connecting the 7 pin harness to the RV. Testing the 7 pins on the LC with a multimeter, and can’t get a 12v signal with the engine on. Does the LC send aux power through the hitch harness?

You do have the LC running correct?

 

[Scylth]

You do have the LC running correct?

Not sure what you mean by “correct”, but everything works good, including trailer lights.

 

[RET2]

Not sure what you mean by “correct”, but everything works good, including trailer lights.

Sorry on my lack of clarity, I was asking bout having the engine in LC running.

 

[hankinid]

Sorry on my lack of clarity, I was asking bout having the engine in LC running.

There's no continuous 12V+ when connected to the truck. The only continuous connection is through the ground wire.

 

[Scylth]

Sorry on my lack of clarity, I was asking bout having the engine in LC running.

Yes, engine was running (good thought, though).

 

[Scylth]

There's no continuous 12V+ when connected to the truck. The only continuous connection is through the ground wire.

There has got to be a way to pull this off. 7 pin connections are usually wired to have a 30 to 40 amp 12v+ to charge trailer batteries. I’m going to have to do some digging.

 

[Trd4rvapeur]

I bought the hopkins 3 months ago, never tested it.
You guys don't know how hilarious this is... I went yesterday to U-Haul to rent a trailer. Of course, the hopkins didn't work because i connected it to the passenger side wiring. Only thing that worked was the driving lights....

Thanks for the revival of this thread, or else I would have posted the same question.

 

[FrazzledHunter]

There has got to be a way to pull this off. 7 pin connections are usually wired to have a 30 to 40 amp 12v+ to charge trailer batteries. I’m going to have to do some digging.

The LC does have a continuous 12V aux power but I'm not sure at what current. But judging from the size of the wires it isn't much. So while it could be used for charging I guess it wouldn't do anything for a deeply discharged battery. And then there are different battery chemistries that won't charge at 12V.

We didn't try to charge the battery while towing on our previous trailer which had a hitch mounted a flooded lead acid deep cycle battery and the fridge was 120V/propane. So 12V into the trailer wouldn't have helped with that.

I'm currently researching how to do this myself not only to charge batteries but to run things like the fridge while under tow.
I've found a lot depends on how your trailer is made and what kind of battery(ies) it uses.

I'm trying to figure out how to best run 6 GA or bigger wire from our 2nd passenger-side battery to the rear of the LC and possibly having a DC-DC charger at or near the hitch.

If you have the proper setup on the trailer then the problem is solved. One trailer we looked at, a Black Series, had lithium batteries inside the trailer and an Anderson SB-50 connector right at the hitch area to power the trailer and also run the fridge. They literally solved the problem for us and it would eliminate the need for a DC-DC charger at the battery near the hitch. All I'd have to do is get power to the rear of the LC.