Trailer Hitch Wiring /4 Flat /7 Blade

[Expolander]

Has anyone tried this fitment or know if it will work for sure? I realize etrailer says it won't but looks like it works on other Toyota vehicles so I wanted to double check with the 200 Series pros. Mine is a 2008.

Hopkins Plug-In Simple Vehicle Wiring Harness for Factory Tow Package - 7-Way and 4-Flat Connectors
Item # HM43385

 

[Hoosier Daddy]

Hopkins Plug-In Simple Vehicle Wiring Harness for Factory Tow Package - 7-Way and 4-Flat Connectors

I used the one above. Bear in mind it plugs into the plugs under the driver side of the truck and not the plugs on the passenger side. I wanted it mounted in the factory location, 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 to splice in.

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

 

[Expolander]

Thanks @Hoosier Daddy. So does the 7pin plug connector - plug into the existing LC side 7-pin plug connector on the LC?

While the 4-pin connector plugs into and existing OEM connector the driver side as well?

Do you happen to know the difference between driver side plugs vs passenger side connectors on the LC?

I need to wire in my ARB harness lights as well, but that is in another thread and I think I have what I need for that. I just wanted to use the option above since it has the plugs already and I can extend the plug as you suggest.

 

[Hoosier Daddy]

The harness you linked and the one I linked both replace the OEM 7-pin trailer plug. The OEM unit plugs into a pair of connectors under the passenger side. From those connectors, there is an OEM wiring harness that runs behind the rear cross member to an area just above the muffler on the driver side. There it connects to another set of plugs. So there are a pair of plugs on both sides, and the OEM plug/harness uses both sets.

The Hopkins harness involves unplugging the OEM harness from the plugs on the driver side. The OEM unit would then be non-functional. So you won't have the OEM unit and the Hopkins unit unless you splice them together with some creative wiring.

The Hopkins unit plugs into the plugs on the driver side. The wires are too short to reach to the OEM location, which is why you would need to spice in an extension if you wanted it on the passenger side. The Hopkins unit would fit the plugs located on the passenger side, but my understanding is that the wires swap around in the harness between the two, so the two sets of plugs (driver vs passenger side) are not pinned the same. So even if the Hopkins unit fits the passenger side plugs, the connections won't be right.

I'm assuming you're just wanting to add the 4-pole flat connector?

 

[Expolander]

Yes, I want to unplug the OEM 7pin and use the Hopkins 7 and 4 pin plug and play option in place of the oem.

 

[KLF]

I have one of these, works great.

Reese Towpower 74607 7-Way to 4-Way Flat Blade Wiring Adapter https://www.amazon.com/dp/B000CPI6VI/ref=cm_sw_r_apa_i_fJ9sCbGZW3CKW

 

[4gotalot]

My solution from the OEM 7 round to a 4 flat was to disassemble the OEM 7 round plug, (at the work bench) solder and seal each wire onto the appropriate wires for a 4 flat then out the back of the OEM plug and securing the new extension 4 flat behind the frame crossmember to and out the lower right corner of the receiver hitch area with enough slack wire to pull the 4 flat out and handle while plugged in and then pushed back flush when not in use. The OEM 7 round plug is still fully operational but at its original location. I did bend the bracket to tuck it up under the body or it would just get ripped off when off road.

If you ad an adapter that plugs into the 7 round to get the 4 flat you will still need to get/make a pig tail extension to reach the pivot point at the ball. Don't forget to secure it in a couple of places because if the plug falls out while driving it will destroy itself skipping of the ground at 70 mph.

Since I do not use the OEM 7 round, I would open the covering wash out any posable road salt, stuff a paper towel in the plug for a day or so to let dry and then hose the inside of the plug and contacts with LPS 3 to prevent corrosion and close the cover after you clean the seal.

 

[hankinid]

My solution from the OEM 7 round to a 4 flat was to disassemble the OEM 7 round plug, (at the work bench) solder and seal each wire onto the appropriate wires for a 4 flat then out the back of the OEM plug and securing the new extension 4 flat behind the frame crossmember to and out the lower right corner of the receiver hitch area with enough slack wire to pull the 4 flat out and handle while plugged in and then pushed back flush when not in use. The OEM 7 round plug is still fully operational but at its original location. I did bend the bracket to tuck it up under the body or it would just get ripped off when off road.

If you ad an adapter that plugs into the 7 round to get the 4 flat you will still need to get/make a pig tail extension to reach the pivot point at the ball. Don't forget to secure it in a couple of places because if the plug falls out while driving it will destroy itself skipping of the ground at 70 mph.

Since I do not use the OEM 7 round, I would open the covering wash out any posable road salt, stuff a paper towel in the plug for a day or so to let dry and then hose the inside of the plug and contacts with LPS 3 to prevent corrosion and close the cover after you clean the seal.

The OEM round connector isn't especially moisture / dirt / crap-proof. Mine was new to me with ~60K, receiver showed no evidence of towing, and my own post purchase inspection showsd sand, dirt, and a few pine needles. I hit it with simple green and water, contact cleaner, brushed the hell out of the contacts and used silicone grease lightly on anything metal inside. 'Yota uses a half-arse rubber seal for the cap that's inferior to Hoppe.

My fix will be to pull the oem harness and splice in a Hoppe. That's gonna wait until springtime.

 

[KLF]

I agree that the factory round cover on the back of the plug is not well sealed. I've had mine apart as I added wires to power auxiliary backup lights in my bumper and will need other connections eventually. I cleaned it thoroughly, then stuffed it full of dielectric grease. After putting the round cover back on, I put a sheath of Grace flashing tape over it, then a final wrap of electrical tape.

The cover on the round plug has a hook that engages the adapter, so it can't fall out (it's actually hard to remove). And both trailers I use have very long wires on them, but I also keep a 2 foot extension in the truck just in case.

But I do like the idea @4gotalot worked out with the connector hiding behind the bumper plastic right at the hitch point.

 

[CGP]

I have one of these, works great.

Reese Towpower 74607 7-Way to 4-Way Flat Blade Wiring Adapter https://www.amazon.com/dp/B000CPI6VI/ref=cm_sw_r_apa_i_fJ9sCbGZW3CKW

I use one of these as well and even found one with an led so you know when you have a good connection. Makes it easy to check, no led signal = not trailerlights.