2005 Tacoma locker Mod

[tacosupreme]

It's a pain in the neck to post pics here, so I did the writeup at cardomain. Click on my signature and read the writeup on page two and if you have any questions ask. Last night I tried to do the factory switch with a DPDT relay version of this mod and couldn't get it to work. I know it does, tbrown did it, maybe I have too small of a relay. The only one I could find was 5 amps.

[crawler#976]

2005+ Tacoma Locker Mod

By Kevin Knight (ComAttack)

This Mod will allow you to activate the Rear Differential Lock on TRD Off-Road Tacomas (2005+) in 2HI & 4HI in addition to 4LO. (Similar to the 2004 “Grey Wire Mod”) It also utilizes the ECU to disable ABS & VSC with the locker engaged (standard feature), just as it normally would. This is a pretty straightforward modification that requires no special skills except a minimal understanding of electrical circuits and wiring schematics. You can perform this mod simply be identifying the correct wires and wiring them as instructed. Your typical “DIYer” should be able to handle this without a problem. Some write-ups show you how to use a second switch. This one will show you how to wire up your OEM Locker switch to keep things factory looking…

*DISCLAIMER: I take no responsibly for any damage, malfunction, or misfortune that occurs as a result of this modification. These instructions are provided simply as a GUIDE to assist you. You assume all responsibility and risk to yourself and your vehicle in performing this mod. If you are not qualified to work on your vehicle, please have it done by a professional.*

Ok, now that that’s out of the way. Let’s get started…

Here is what you will need:

(1) 10A DPDT Relay (double pole, double throw) (20A would be better, but 10A will probably work fine), female Spade Crimp connectors (a dozen will be plenty, and leaves room for some error)
(2) Wire Tap connectors, typical hand tools (wire cutters, crimper, screwdriver, etc) Optional supplies, Depending on where/how you want to install the relay:
Extra wire Heat shrink, solder, Electrical tape

First, an Explanation about the DPDT Relay.

A DPDT relay is a switch that has two inputs (poles) and two outputs (throw) for each input. Basically 2 in & 4 out (or 4 in & 2 out, depending on how you look at it). A relay requires electrical current to pass through a magnetic coil to flip the switch. The type of relay we need will have an “off” position when no current is applied and an “on” position when current is applied. DO NOT get a “Latching” DPDT relay. A latching relay is one that requires current to flip the switch, and then requires the current to be REVERSED to switch it back. This type will not work with the OEM Tacoma switch. There are also many types of configurations for the same type of switch. This simply means that the contacts may be in a different position than the diagrams used here. You can figure out what each contact is by looking at the diagram on the switch or an illustration that came with it.

Here is a sample of some different configurations:

If you choose a switch with a slightly different configuration, for sake of illustration, I’ve labeled the Relay contacts in the diagram above. The “poles” are A & B. The “throws” are A1, A2, B1, & B2 and correspond to the accompanying pole. For reference, in the default “off” position, A & A1 have continuity, and B & B1 have continuity (A2 & B2 have none). The coil contacts are generally turned a different direction for ease of identification. If you check the resistance with an Ohm meter, it should read a couple hundred ohms. The other contacts will have very little if any resistance.

How you mount the relay is up to you. You can let it hang (not recommended...wires may come loose). Or you can just tape it to the ECU or wiring harness. Whatever works.

Now get out the tools and let’s get started!!!

You will find the 4WD ECU on the passenger side behind the glove box. Remove the glove box and 10mm bolt on the latch. Then remove the black plastic cover held in by latch bolt. Once you have access to it, identify the connections you will modify in the picture below. You will need to cut 5 wires from the harness. One you will leave intact, but you need to tap it for power. I have labeled each of them in the picture for easy recognition. Make sure the ignition is in the OFF position and the locker is DISENGAGED before starting.

• Begin by carefully cutting back (or unwrapping) the electrical tape around the wire. You will need to give yourself several inches to make the work easier. The
more the better. You can always re-tape the wires if needed. (Removing the ECU is optional).

• CUT the ‘Lt. Blue’ & ‘Lt Green’ wires and put a spade connector on the ends. These are the leads to the actuator motor. ‘Lt. Blue’ goes to “Pole A” and ‘Lt
Green’ goes to “Pole B.”

• CUT the ‘Pink’ & ‘Lt GN/Black’ wires. These go to the limit switch, and will activate/deactivate the motor to engage or disengage the locker. Attach spade connectors. ‘Pink’ goes to A2 & ‘Lt GN/Black’ goes to B1.

• TAP the ‘Violet’ wire. DO NOT CUT IT!! This supplies power to the ECU and also the actuator motor. It is adequately fused, so we will continue to use it forour new circuit. You will need to attach TWO wires to this power lead. I suggest making/soldering a small Y-cable. Insulate it with heat shrink tubing. Using the tap connector, tap the ‘Violet’ wire with one lead from your Y-cable. Or you can use 2 wire taps and tap the ‘Violet’ wire twice. Attach a spade connector to the other two ends and connect them to A1 & B2.

• Cut the ‘Red/Black’ wire. This is for your OEM switch. (The wire is hidden behind the ‘Wht/Blk’ wire in the picture.) Attach a spade connector, and connect it to one end of the coil contacts. It doesn’t matter which.

• To the other coil contact, attach a wire with a spade connector and run the wire to any ground point. You can simply tap into the ‘Wht/Blk’ wire on the ECU if you like.

• Verify ALL connections are in the proper location. Double check everything! Tape the relay to the ECU or wire harness to make sure it won’t bounce around. If you want to relocate the relay somewhere else, you can lengthen each wire you cut by splicing in another wire to each, and mount it elsewhere.

YOUR DONE!!

Put everything back together. Lock up that differential and go have some fun!
__________________

[rlin0997]

thanks guys!

[ski05]

I can't get the link neither. but I did find an easy fog light mod on the link.

[ski05]

Nice! In your article, you refered to some pictures??? I can't see them.

[tacosupreme]

Read the whole thread, and either register at TS for free, or read my half ass writeup by clicking my sig.

[fifthcircle]

Originally Posted by tacosupreme

Read the whole thread, and either register at TS for free, or read my half ass writeup by clicking my sig.

I would reccomend registering at TS. The copy/paste above does not do the write-up justice. The original with all the pics is wicked good and stuff.

[ski05]

Sorry I am new at this site. What site is TS

[tbrown]

Originally Posted by ski05

Sorry I am new at this site. What site is TS

Tundra Solutions. It's a website.
Here's a link.
http://www.tundrasolutions.com/

[ski05]

Thanks, I should have known that, I believe I have seen that here before.

[Comattack]

Sorry for all the difficulty... I'll try to see if I can post my write-up here tomorrow. The PDF is at work, so I'll have to do it later.
(besides, it's WAY past bedtime!)


I take cash or credit...... Just Kidding!




Anyway, I'll find someway to make it available to you, soon!

[Comattack]

Here's the write-up i posted over at TundraSolutions (TS).

Man this was a MAJOR PITA to convert, resize, host and all that S***!
Hosting was giving me all kinds of problems... I sure hope you guys are grateful! j/k

Two things I should mention...
First, You must use a DC relay (direct current). An AC relay will NOT work.
Second, once you cut the wires, you will connect to the wires on the Harness side, NOT the wires going into the ECU. You are essentially disconnecting from the ECU completely and wiring up a new controller for it.

I had to split the pages into chunks to keep it from being distorted when I uploaded it. Pictures are still pretty large, so they are plenty readable.
Let me know if you have any questions.

Page 1a
Page 1b
Page 2a
Page 2b
Page 3

[iaintdumb2]

Has anyone else done this with success? I'm mechanically and electrically inclined, so I'm not a complete idiot.. But my truck is now stuck in 4lo and the diff lock won't turn off. Well, the indicicator lamps in the dash won't at least, and now my ABS light is on. I've even wired everything back to how they originally were, but everything is stuck on. I've even pulled the 4wd fuse and disconnected my battery to reset everything, but I can't get the lights to turn off (without the relay connected). Any help is appreciated..

Megan

[Comattack]

2 things come to mind...
Did you check the fuse when you pulled it to make sure it wasn't blown?

Second,
You may have the relay wired correctly to engage the locker, but not to disengage. Although I donno how you'd do that...

ABS is automatically disabled when the locker is engaged so that is probably why it came on...

You shouldn't have to mess with the 4WD switch at all to get it working. So why in 4LO?
If the locker engaged succesfully with the relay/switch (indicated by all the lights.. VSC, ABS, locker), then you might want to double check the other circuit. As I mentioned in the write-up... if you have a "latching" relay, you need to REVERSE the power to the coil to get the relay to switch off... which is the relay you don't want, but give it a try. It shouldn't hurt anything. Just keep an eye on that fuse, so you know if you short anything or not.

Could be several things... Take a look at those and let us know what you find.

[rogersja63]

Originally Posted by iaintdumb2

Has anyone else done this with success? I'm mechanically and electrically inclined, so I'm not a complete idiot.. But my truck is now stuck in 4lo and the diff lock won't turn off. Well, the indicicator lamps in the dash won't at least, and now my ABS light is on. I've even wired everything back to how they originally were, but everything is stuck on. I've even pulled the 4wd fuse and disconnected my battery to reset everything, but I can't get the lights to turn off (without the relay connected). Any help is appreciated..

Megan

It may not lock/unlock or go in and out of 4wd unless you are driving around, turning the steering wheel, etc. I don't know how much you've wheeled the new truck but mine was reluctant to operate when it was brand new. Had to break it in a little.

[iaintdumb2]

double edit...

So I found my problem. I sat down to check if my relay was ok (checked continuity between posts, etc) and since it has a clear casing, I realized that I had mixed up the pins. So it's all my fault, haha.. I blame it on all the late night spray painting in my garage

Megan

[iaintdumb2]

Another update.. My wiring is all correct, and for sure this time. However, my 4wd fuse is still burning up. I found that the green and violet wires always have continuity, straight from the harness. When I unplug the harness from the ecu, they don't, so somewhere in the ecu they're connected. From my understanding of all the schematics and diagrams that I've seen, they shouldn't. Someone please correct me if I'm wrong. I can't find anything else wrong with how I've wired it. I've managed to turn this simple mod into a nightmare. Any help is greatly appreciated!

Megan

[tacosupreme]

Sounds like you are hooked up to the ECU side of the wires to me. You need to be hooked up to the part of the wires that run up into the black tape, not the ones that go to the connector. And the violet wire is Positive. If you are grounding it out, it will overload the fuse. The good news is you aren't the first person to do one this way, and the ECU (black box thingy) seems to survive repeated arc welding experiments. Hope this helps, PM me if it doesn't.

[jungleman]

So.........this is where the off roaders hang out

I just wanted to personally thank everyone who worked on this mod I did the locker and 4lo mods last Friday and gave them a thorough workout.
Both work great

Thanks tacosupreme for helping me with the 4lo thing, I shared it with the guys at toyotanation and got pretty much the same response, a couple of way cools and several no way in hell would I do that

THANK YOU EVERYONE

[mandzach]

I bought my truck like 10 days ago -07' TRD DC 4x4 and really want to try this mod.

07' is the same as 06' I am assuming - All wire colors should be the same.

Just wanted to check with you guys to see if this is the most current "locker mod" to date. Any updates or changes worth mentioning?
I searched the crap out of this and think this thread and links are what I am looking for.


Thanks-

[rogersja63]

Originally Posted by mandzach

I bought my truck like 10 days ago -07' TRD DC 4x4 and really want to try this mod.

07' is the same as 06' I am assuming - All wire colors should be the same.

Just wanted to check with you guys to see if this is the most current "locker mod" to date. Any updates or changes worth mentioning?
I searched the crap out of this and think this thread and links are what I am looking for.


Thanks-

Yep, the same.

[Comattack]

Originally Posted by rogersja63

Yep, the same.

For a sec, I thought you meant you were in the same situation as mandzach.
But I get it...

This mod was for 05+ Tacomas; so yes, it will work for anything after '05 as well!! Good luck!

[wicked2007]

Thanks for all of the information. I am going to try this mod out. I just got done making a little harness so the install will be easy. I followed Kevin Knights write up...

Full Harness


DPDT Relay and Socket


I will let you know the results once I install this.

[mandzach]

Originally Posted by wicked2007

Thanks for all of the information. I am going to try this mod out. I just got done making a little harness so the install will be easy. I followed Kevin Knights write up...

Full Harness


DPDT Relay and Socket


I will let you know the results once I install this.

I missed that write up I think -
Do you have a link or just the part numbers for your parts?

[wicked2007]

Originally Posted by mandzach

I missed that write up I think -
Do you have a link or just the part numbers for your parts?

Well I just used his wiring diagram, its linked off of one of the lages in this thread - I was just looking for a little more of a clean install so I could replace the relay if necessary.

[wicked2007]

Just a quick update - finished this mod today and it works great

Locker on with ABS off in H2, H4 and L4

Thanks for the information to get this done!

[mandzach]

edit -found it

[mandzach]

Finished the mod - locks in quick but not all the time instantly - seems like the truck still needs to be traveling slowly to get it to lock in, is this normal.

[wicked2007]

Originally Posted by mandzach

Finished the mod - locks in quick but not all the time instantly - seems like the truck still needs to be traveling slowly to get it to lock in, is this normal.

Mine reacts similar to the way you describe. Sometimes it goes right on then others it takes a bit of slow driving. I noticed turning the wheel a bit helps.

[ah64id]

Originally Posted by mandzach

Finished the mod - locks in quick but not all the time instantly - seems like the truck still needs to be traveling slowly to get it to lock in, is this normal.

Yep, there are splines that need to mesh to get it to lock, if they arent lined up it wont lock. One reason for the 5mph limit on locking, if your going faster it can mess up the locker..