Lock, Stock, and 2Wheel Low (3rd Gen DIY Mod)

Finally found time to get this done!! It’s been on my list of most important things to do since I bought the truck. I have an ‘18 MT, and can confirm it all works as it should. Following the instructions made this fairly straight forward. Chopping into the small wiring was a bit unnerving! But what a difference backing up in lo range now.... no more wind-up and easy steering!! Thanks BigWhiteTRD for taking the time to post such great instructions and answer a few PM’s about completing the mod!!
I used an AironBoard switch, with the Meso 7 switch panel in the lower center console. As mentioned earlier I used bullet connectors, while ugly, can easily pull the relay out and hook everything back up.

 

Nice work! Thanks for posting!

 

Thanks for posting your results. Glad it worked well for you.

So looks like mod has now been verified working for manual and automatic trucks.

 

I have a set of male and female 10 and 40 pin connectors on the source mentioned in the Lock anytime thread. I would like to combine the two mods into one "plug and play harness" as you have mentioned.

 

Look what showed up today... getting closer I picked up 2 of the relay boards, to hopefully make for a neater install, and one that is easier to troubleshoot in the future. Now I need to pick up the wire in the proper colors to build out the harness

 

2 Lo is awesome. I have a 2016 Tacoma Sport 6 speed manual. If you have a MT and back up inclines, or use your truck as a truck & haul weight in the bed or pull trailers, backing up is now easier & less wear on your clutch. There is also will be less wear on steer knuckles & less binding. Backing trailers with 90 deg angles on flat land is no longer an issue. When backing in with 2 Hi you can smell the clutch burn, with 4 Lo steer knuckle binds. If you do that often the clutch will have to be replaced prematurely (yes 45K miles). If I had done this sooner I wouldn’t be replacing the clutch.



It was a bit unnerving cutting and splicing wires on my own vehicle. Thanks to BigwhiteTRD (OP) and Thunderchicken for being able to pick their brains and help me out with the wiring & what I was doing wrong.



I could never start in the middle of the driveway which is on a steep incline. The Sport has a 3 sec. brake hold unlike the offroad . No matter how hard you try or what techniques you try the truck always goes the opposite way you want to go and have to slip clutch to go. After installing the 2 Lo mod, I stopped in the middle of the driveway and I was able to back up with no problem and turn at the top on concrete. Its amazing how easily it allows you to use the 4x4 operation dial. No hassle anymore. If you have had trouble going into 4x4, the 2 Lo mod makes this easier when switching the dial to 4 Lo to use the 2 lo mod. Now when switching into 4x4 it goes right into 4 Hi. With this mod if you use the clutch cancel switch to start the truck the clutch pedal does not even have to be used to put into 4 Lo for the 2 lo application. All you have to do is push 2 Lo button click into 4 Hi and then come to complete stop or 2 mph or below and click to 4 Lo. No dogging or having to go fast .backing up the driveway anymore .

Thanks to BigwhiteTRD for this mod. Definitely save on clutches. More mods would be appreciated like a 3rdgen ABS kill.

 

Thanks for giving it a shot and seeing it thru. It takes alot of confidence to overcome the fear to hack into the wiring of a new truck.

So total of 3 trucks modded. Guess I should start a table of truck configs modded.

I am writing a revision to the instructions to include post mod check-out procedures based on Calmlikeabomb (Chris) experience, that was definitely not something I covered enough I see now

 

Thanks for the first adopters, and the feedback to improve instructions.

First post updated to include the trucks that have been modded so far, (as far as I know)
Also, first post pdf updated to include some more wiring details, and checkout instructions for the mod. Recommend downloading lastest copy from first post

 

Any news on this?
I would be interested

 

No news from me, sorry.
Just got back into country, and worked on it a bit today, but had a batch of shitty wire that doesnt solder worth crap, so didnt get any further along today. Ordering some better silver plated wire and get back to it in a week or 2.

 

I just ordered the connectors from Rakuten. I'm going away for vacation at the end of the week, so I definitely won't have an update for a couple weeks either. I have everything else needed, so hopefully it will be a simple plug-in harness build.

If this works out, I work in the same building as a company that makes wire harnesses for military applications. It may be possible to have him make up several. I'm going to hold off investigating that until I get mine made up.

 

This is sort of a dumb question, but I'm assuming that the resistor is intended to fool the computer into thinking the actuator is still there right?

I had some free time after packing for my flight tomorrow and got the connectors pinned up. I still need to do the relas, resistor, and splices in the 40 pin connector.

 

Agreed re off road and im always in 4wd when using the boat ramp.
The people that dont are the strong contributors to the boat ramp bloopers videos!

 

Looks good
Man that is alot of wires into the ECU.

You are correct, the resistor is so that the ECU thinks the motor is still connected. It checks that resistance on engine start, and every 4wd mode change...(2hi -> 4hi, 4hi->2hi, 4lo->4hi, etc)

The reason that I call out a high power resistor is for failsafe conditions. If you switch the dash switch to 2wd with the 2lo switch engaged, the ECU will send power to the resistor for about 30 seconds before it throws codes.. and the power resistor seems to absorb it just fine without cooking under the dash.

 

Thanks, not my first rodeo pinning connectors. Lol! Those tiny crimps on the 40 pin connector are a pain in the ass though.

Safety factor on the resistors is a good thing. At 14v a 10ohm resistor will dissipate almost 20W. If the resistor is only powered for 30s at a time then even a 50W would be more than adequate. I thought the resistors I had were 20ohm 10W, and I was going to put them in parallel to get the equivalent. Unfortunately theyare 10ohm 10W which isn't sufficient. I'll have to pick one up locally or from Amazon.

I was also looking for a more compact relay arrangement, but haven't come up with something that wouldn't require additional work. The cost/benefit isn't there for me personally.

I just wanted to confirm the pinout on the 40 pin connector. The diagram in the PDF is showing the wire side connector (female with sockets for pins), looking at the face correct? I haven't taken my truck apart to confirm wire colors and wanted to have the harness ready to go so I only had to do it once. I was able to figure out the 10 pin connector since it has keying features, but the other one doesn't have any.

Also, is the yellow (F12, pin 4) switched 12v with the ignition?

 

Note
That resistor only gets significant power in the failure cases. In the normal operation, that resistor only sees pulses for milliseconds. 30 seconds of power is just if something goes wrong or operator error until it throws codes.

Will double check on connector, off head 90% sure it is mating face of connector.

Will double check on that power pin. Off head 99% sure it is keyed switched 'engine on'.. but might also be in 'accessory'

 

Got it.

Just so we are on the same page, this is how I assumed the diagram was showing the connector.

 

Verified your colors look correct per my understanding, and looks right to some pictures I took

Verified the power I pulled from (F12 Pin 4) is 12v switched power (12v with ignition on), although any source of 12v switched should be fine.

Not greatest picture, but this helps verify it.

 

Good deal, thank you. I guess I should have looked and verified that all the pins were actually used before crimping them all unnecessarily.....