3rd Gen Spoofer Development for ADD and Transfer Case Actuators

The manual T-Case replaces the Automatic T-case (sometimes called FJ-T-Case-Swap). The manual T-case has indicator switches you wire up to the automatic T-case T4 plug to indicate when you have shifted into 4WD-Hi and 4WD-Lo. Right now I can use full 2WD (Hi/Lo) and 4WD (Hi/Lo) with ADD and anytime rear elocker. I just want to see if I can get the 4WD ECU spoofed so everything is working to use Toyota's other Offroad options like traction control etc...

If you have a Toyota elocker on a 3rd Gen you can do an anytime rear elocker using the Eaton Elocker Universal wire harness. That is what I have done and it works perfectly other than the 4WD ECU not being happy about it. I am not using the stock rear elocker button, instead I have the universal wire harness connected to an 8-gange switch panel. I do not want to do ARB air lockers for my own reasons, but done right they are great lockers.

 

I wasn't aware of this, thank you. I must have been remembering the 2nd gen modification.

 

@rmack
Are you saying you found both the Male and Female connectors for T4 (xcase connector)? If so, could you please share.

I made up a cable extension (9"-12") for the addition of a crawl box between the AT and the xcase. This was done by unpinning the 9 contacts of the 12-contact female connector(T4) and reinserting them into female 4-contact and 5-contact connector. My pigtail has the Male 4 & 5 contact connectors at one end and the original female 12-contact connector at the other end.

I was unable to find the male 12-contact connector that resides on the xcase.

Its late go to bed and answer in the morning.

 

@Toycoma2021 - no unfortunately I didn't find one. I looked everywhere I could think of... Instead I cut each wire one by one from the T4 line and used a new adapter (https://a.co/d/6oRU9Q6) to connect them all back. I made sure to cut far enough back so I could reuse the original plug and connect it to my new connector if for any reason I wanted to use an automatic T-case again.

Note: I wired them all back the same with the new 12 pin connector. If I need to I can buy the same connector and mate it to the original connector and go back the auto-T-case

 

Under the truck ...

 

Dang, thought you might have solved a sourcing problem. Oh, well.

If your project goes into production, I would suggest for simplicity's sake finding compatible connectors to the 12-contact (in a format that is not 12) and forgo the cutting and just move pins around where need be making it all reversable. This would make it a bit easier for those not so inclined to "cutting" up their wiring. Sumitomo connectors iirc.

 

OK, need to go to bed soon...

I found this which looks just like the T4 plug .... "1JZ Non-VVTI Ignitor Connector" and when searching for the male side I found this ...

https://www.wiringspecialties.com/copy-of-1jz-non-vvti-ignitor-connector/

Everything looks right, but I don't know the size ... I would have to order one to figure out if it would work.

Search for "1JZ Non-VVTI Ignitor Connector" and you will see it looks pretty much identical. Only the Wiring specialties place has the male that I could find, but hey maybe this will work for you? It does cost $41 .... maybe if it works piece of mind for not cutting wires?

 

$41 dollars for the Male connector - no way. Even if it is the correct one. Their female connector was $16. They must know what they have and want real money for it.

I will have to go through the Wiring Specialties web site sometime to see what they have of interest. My impression of the site so far was of another site I found that catered to those people/mechanics that were desperate to get the right part the first time for their customer. Despite the cost.

I am not cutting wires, but de-pinning the connector and putting the pins into other, compatible connectors. Very reversable. Connectors come in families with different number of cavities, all taking the same pins or contacts.

Have you seen these suppliers?:
Sumitomo Motorsport Connectors - Corsa Technic good prices and availability

Ballenger Motorsports - High Performance Electronics

自動車用部品:Sumitomo Wiring Systems, Ltd company website

tss.pdf Sumitomo pdf catalog for one family.

SUMITOMO Products - OCO Connectors

Connectors | Yazaki North America not for this project.

 

T-case spoofing latest status. I found one major issue with the 2-Relay design for just spoofing the T-case part. I will need to add in 2 diodes into the solution. Once I am done adding these in and testing I will post my next status.

 

Continuation of post #68 showing the transfer case extension cable for the future crawl box.

 

Latest status ...

Summary based on information below:

• Diodes wired up works to prevent Pin 1 F13 from being grounded
• 4WD F13 wire harness plug reconnected throws code and dash lights (error)
• Still haven't tried shifting due to 4WD F13 wire harness plug issue
• Rear elocker original plug still in over anytime locker harness as the elocker will also need to be spoofed

Latest status ... investigations... Actions and Observations details

Old action still in place, remove observations based on new Action-4

• Action-1: Disconnect T4 Wire harness from T-Case AND Disconnect Pin 1 from Relay 2 & 3 (4WD & ADD)
  • Note: All relays should be in default 2WD condition

• Action-3 w/ action-1: Disconnect Truck F13 Wire harness from T-Harness but keep T-harness w/ relays etc... connected to the 4WD ECU.
  • Note: No connection coming from Truck T4/ADD plus etc F13 wire harness plug

Slimming down possible issues to investigate:

• Why-1 is Pin 1 F13 that is not attached to anything on the Truck only the T-Harness (Relays) and 4WD ECU grounded?

• Hypothesis: Pin 14 on F13 coming off of both Relay-2 Pin 87 and 87a grounding other circuits
• Experiment: Add diodes from Relay-2 Pin 87 and 87a on Pin 14 going to F13
• See Action-4 below

​

• Why-2 does connecting the Truck F13 wire harness to the T-harness make the ECU throw codes?

• Action-4 w/ action-1 & action-3: Diodes wired up inline with Pin 14 on F13 coming off of both Relay-2 Pin 87 and 87a
  • Note: All relays should be in default 2WD condition
  • Observation: Pin 1 F13 (4WD-Hi) NO longer grounded
  • Observation: Truck power on with 4-Lo dash light OFF and NO error code thrown
  • Observation: Relays get power
  • Observation: Hypothesis correct with why-1, diodes do in fact fix grounding of Pin 1 F13

• Action-5 w/ action-1: Reconnect 4WD F13 wire harness plug into T-Harness, so remove action-3

• Note: All relays should be in default 2WD condition
• Observation: Truck power on with 4-Lo dash light ON and error code thrown
• Observation: Relays get power
• Observation: Why-2 problem not solved, with no further investigation yet.

​

 

Latest status as of today.

• When powering on the truck with the truck F13 wire harness not plugged into the T-Harness no codes no dash lights default mode 2WD (appears to work)
  
  • When trying to energize the 4WD-Hi relay to turn on 4WD-Hi but it doesn't go into 4WD-Hi - nothing appears to happen (no dash lights no codes thrown, nothing appears to change)
• When powering on the truck with the truck F13 wire harness plugged in the 4Lo and 4WD lights blink ...

I need to take a break from diagnosing so I can weld in my new support for the crawl box (works without, but I want it in) and I need to prepare for a wheeling trip this weekend. Will try again on Sunday.

 

I have been a bit busy, still planning on trying some extra stuff, but right now what I have isn't working right. I don't think it is the circuit design, I think something else is wrong with the truck.

Here is the 2 relay setup I came up with to spoof everything so far. I might make updates, but just in case anyone else wanted to try it.



Here is the design for the ADD, credit goes to @BLtheP on this one.

 

With an FJ case swap on a 3rd gen Tacoma.
If one did not care about dash lights working (4wd or 4lo) but wanted to keep the 4wd ECU happy so the e-locker works with an anytime locker system. Could the transfer case actuator just be removed from the original TF case and left plugged in elsewhere? Assuming the timing of actuator was set correctly. All the sensors are in the ADD and TF case actuator that communicate with the 4wd ECU as far as I am aware.
I have personally removed my ADD from the front diff and moved it to a safe place out of the way of water etc.. I replaced it with a solid shaft from a Lexus GX470.

 

Yes, a lot of people already do that with the actuators tied up somewhere plugged in. My goal was to try to be able to get away without doing that for those swapping.

 

As @BLtheP mentioned ... but I also don't want that thing in my truck if I don't need it. Also you can simply install a new wire harness to get the rear elocker going as an anytime elocker. The information @BLtheP posted should work, the 2 relay system I came up should work. I just need to figure out what else is wrong with my system. I have other projects going on, but I will be coming back to this one.