Trailer Brake Converter

My 02 AC has the factory tow package and I recently R&I the hitch to repaint it and correct the snapped bolts that mount it. Now that it is reinstalled I am adding a new 7 pin connector (Hopkins 40974 and 40985) however I've found that I am not getting any power to the "trailer socket" connecter behind the rear bumper that would have originally led to the factory 4 pin. All fuses are good and all exterior lights work. I suspect the issue is the trailer converter behind the drivers taillight. What are my options for replacement? I don't see any plug and play options available. Do I need to wire in a universal converter? Do I need a converter or can I just splice into the taillight wiring? I've seen past threads with the same issue but no solid answers were given. Thanks in advance!

 

Do you have the black box for trailer/tow package behind your driver tail light? If yes, are you getting power to it?

I wouldn't splice into the tail light wiring. The power wire isn't going to be stout enough. And if you do it, DO NOT be a fucking idiot by using quick-taps/quick connects/scotchlok/t-taps/whatever you want to call them. It's a hack, that literally hacks up your wiring, and will come back to haunt you later.

 

Yes I have the converter. I have not checked for power going in as my service info does not designate which wire is what (I need to download and check FSM)

As far as splicing I know its not ideal and not how I prefer to do things but it would just be for the "4 pin" functions (lights). Separate wires will be run for the 7 pin functions (12v and brake controller). I definitely won't use scotch locks... that's why I'm replacing what was there lol

 

I assume E on the converter would be power in? Most of those abbreviations don't make sense to me...

E = ?
TRNL = turn left
STLO = ?
TL = taillight
B = Brake? Battery?
TILO = ?
TRNR = turn right
STRO = ?
STP = brake lights

That would be my assumptions.

 

Not sure, but it should have a manual or instructions that came with the converter to diagnose that?

Wiring diagrams for your truck are in this thread: https://www.tundras.com/threads/so-you-wanna-buy-just-bought-a-1st-gen-tundra-eh.115928/

Right near the top, and once you have it, I think "Trailer Socket" is the phrase to search for, although it may be a few search hits deep.

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From the Hopkins site: https://hopkinstowingsolutions.com/doc/trailer-wiring-codes.pdf
And: https://www.hopkins411.com/doc/instruction-sheet/40974_INST.pdf
And: https://www.hopkins411.com/doc/instruction-sheet/40985_INST.pdf

 

Negative ghost rider, E is ground and since your drawing shows wh/blk for E, remember that is ground on our Tundras, along with most vehicles.

Fairly close on others but with the below pic from 02 EWD, the others should make sense.

 

I know the identity of the Hopkin wires, its the Toyota converter I was referencing. I'll study the fsm and try to get back to it this weekend.

 

That helps a lot, thank you!

So assuming the wires going to the converter check out, the question remains what do I replace it with?

 

I would just replace with OEM but the Curt option is fine too and beefier wire to the 4 pin.

OEM gets you access to reverse which is nice. And the wire is already there. But it’s not terribly beefy.

double check the connector up front feeding power to the trailer module. Grey connector one or two position. Should have a fuse of its own. Probe w meter and troubleshoot that end. Then probe the 11 position to confirm it comes out at driver taillight spot and isn’t cut. Assuming all is well with power delivery and no parking light or stop/turn output (blue, red, yellow iirc) output with trailer module connected then I’d consider replacing it. I have a spare. I don’t think it was much more than the Curt and can be purchased together with the 4 pin OEM pigtail then you just plug it in and bolt it up and you have 4 good to go.

from there to 7 is the trickier bit and where I’m at this weekend. I’ll take a closer look today once I’m done with my workout but since reverse doesn’t feed into the trailer module you really want to grab it from the OEM 6 way so there is incentive to go OEM. Otherwise you’d need a separate reverse T somewhere or steal only reverse from the 6 way in the center.

probably should be posting photos since my words are gibberish.

I can get you part numbers too, still have the OEM plastic baggie in my bin.

 

And if you want my Curt I’d part with it since I have two new OEM modules and plan to have 7 pin done so not going to use the Curt for anything. I got it a long time ago, never used it.

 

I would prefer to stay OEM. Looks like that part number is discontinued and unavailable. Where and when did you purchase yours?

I was able to grab another OEM converter from the junkyard yesterday, so I can try that when I've got time.

 

I stockpiled crap over the past few years. I see a lot of posts about “discontinued” and I don’t necessarily buy it, I’ve been able to find heaps of OEM parts for my 2002.

I could dig through old emails to confirm when I bought it but the 4 pin isn’t special, the OEM trailer module is. From there to 7 pin is just finding reverse. A beefy ground, your brake controller of choice and ignition switched power. The last bit is the more complicated since spec says 40A and circuit breaker, many relays are 30-35A max. I just ordered an Eaton 60A relay today, next task there is finding a source for the coil, may end up feeding from the cab. Planning to fuse at 60 and then use a circuit breaker at 40.