3rd Gen Spoofer Development for ADD and Transfer Case Actuators

I was curious by that too. To my knowledge that Speedo would be way off from the 38’s only and would need a recal.

 

So for this did you end up doing what we discussed before? Just running locker with 12V power, using the “locker engaged” signal back to the ECU, and then I’m assuming you put a resistor on the stock locker power wires so the ECU doesn’t complain that the locker disappeared?

 

A lot of information to go through there, thanks.

First off, I think you seem to have enough experience with vehicles to realize everything in 4-wheeling is transitional. Too many people think they are going to get it right the first time.

I can't imagine a State that would not require an emergency brake for street use. Many States, including California do not have physical safety inspections, you may live in one of those. It is my understanding that all emergency brakes have to be a "physical" engagement. Hydraulic does not count, so I have heard; the only way the Electrical brakes qualify is the caliper motor moves the pad into contact with the rotor and somehow hard enough to hold the vehicle, if power fails it is still left in contact and does not move. I have not thoroughly investigated the electric brakes yet. My application would not be the Tacoma, but a Samurai; in which I installed a full-floater and disc brake kit years ago and the emergency brake has never been adequate. Those calipers were off an 80's Subaru with cable actuated caliper emergency brakes.

I'm with the other posters in not understanding just how your speedometer reads the correct speed with tires as big as you have. Unless you have done major changes in that area too. I understand earlier versions of Toyota trucks did the speed calculation in the transfer case, not at the wheels as these 3rd generation Tacomas do.

 

When I was running 35" tires with 5.29 gears my speedo was off as well. I was about 5-7 MPH over. I had to set the ratio to compensate to around 1.1. After installing the 38" tires my speedometer is back to normal. I checked via GPS through multiple applications.

Updated information on this post.
I could be wrong about this information, but I thought the 3rd gen uses both the ABS sensors and a transmission speed sensor? If the ABS system fails it falls back to the transmission sensor only. It could be ... given the ABS stuff isn't working that my speed is only being calculated off the transmission which is why it is reading (what appears to be) correctly.

This was my understanding, which again could not be accurate with speed and the Tacoma.

There are two sensors: ABS and Transmission. The ABS is impacted by tire size, and the transmission is impacted by gear changes in the differentials. The ECU uses both and averages everything out. If you change 1 or both there will be an impact on the speedometer.

 

I haven't started the spoof process yet. I will be getting on this starting this next week ordering the initial parts I need and going over the wire diagrams and information you have provided, thank you.

What I did was bypass the 4WD circuit completely at this time. I want to do this again because I want all electronic driven 4WD components to be on their own circuit. Right now I could technically pull the 4WD CPU completely, but I still want to try the spoofing to get 4WD traction control, ABS, and Crawl Control. I will most likely need to follow your suggestion with spoofing the rear locker as well now. I currently do not have dash light indicators so I will be working this as well. I want to put some thought into this (dash lights) holistically before doing something specific like cutting and bridging wires.

What I did at this time:
I pulled the 4WD CPU fuse under the dash and left the 4WD CPU wires alone at this time. Because I pulled this, the only code I get is the ABS not working right now. (Note: there is supposedly a fix to get ABS working again, but only under 2WD by preventing the signal checking in on the 4WD CPU). I am using the Eaton elocker universal wire harness for elockers(*). The wire harness has everything needed: relay, resistor, power etc... The wire harness needs two power sources to make the circuit work. With this I connected two buttons to turn on the locker. I checked the voltage etc... after everything appears to work as needed. I jacked up the rear of the vehicle spun the tires with the locker off. Tires moved opposite direction. I then turned the locker on and the tires lock with a click and then they no longer move because the locker is engaged. The only indicators I have are in the cab by the switch panels lights being on. (Not the best but good enough through this transition).

(*) I got the harness off of ebay for $150 brand new. I have used them in the past with other elockers and this solution has always worked for me.

 

So, you have one of the calibrators that fits behind the speedometer already?! Rough Country or Hypertech.

 

Hello, I had the Hypertech installed and it is now removed. I installed it with the 35" tires. After going to the 38" tires I changed the Hypertech to 1.0 ratio everything at the dash (speedometer) was accurate doing multiple checks. I also use the OBDLink and w/ MX to check my speeds with both GPS and reading it from the PIDs. I also had OBDLink ratio set to 1.1 which was good for the 35" tires. When checking again after the 38" tires the ratio was wrong but the GPS was right. I switched the ratio back to 1.0 and it now reads the exact same as the GPS.

I do not know the math/calculations(*) used by the ECU between the transmission and ABS sensors. If I did I could figure out what is going on given the gear ration change and the tire size change (**).

What I do know based on observations is this...

• 5.29 gears with 35" tires (true size maybe 34.5") the speedometer was wrong by 1.1 ratio
• 5.29 hears with 38" tires (true size maybe 37.5") the speedometer is correct and matches GPS speeds (note: ABS lights currently on due to 4WD CPU fuse pulled, if fuse in 4WD signals show including ABS).

(*) Update - I think the math will go something like this...?

• ABS - Vehicle Speed = Wheel Rotations per Second × Tire Circumference
• Transmission - Vehicle Speed = (Output Shaft Rotations per Second × Tire Circumference) / Final Drive Ratio (gear ratio)

Transmission impacted by both wheel size and gears while the ABS is only impacted by the tire size. I would need to think about how these are averaged and how things would work normal driving vs wheeling vs tire slipping etc...

(**) Update 2 - After the helpful requests to understand I decided to look into the math side of this situation. After running the some calculations it appears my speedo shouldn't be back to normal if comparing gears and tire size. So I am puzzled and I am going to investigate some more.

Math I used.... (hopefully this is accurate after looking up some calculations) This one is just looking at the Transmission sensor given that I think the ABS sensor isn't working with the ABS dash lights on.

Driveshaft rotations per mile = (total distance in inches per Mile / tire circumference ) x final drive ratio

• total distance in inches per Mile == 63,360 inches

Original tire size and gear ratio (DSR = Driveshaft rotations)

DSR per Mile = 63360 / 95.77 x 3.09
DSR per Mile = 2044

New tire size and gear ratio

DSR per Mile = 63360 / 117.4 x 5.29
DSR per Mile = 2854

This is a 33% difference if this is all correct so the speedo shouldn't match. I will keep investigating. At this it looks like I would need a 51" size tire to be the same as a 30.5" original diameter tire with the gear differences and only using the Transmission sensor.

Update 3 - Thank you @Toycoma2021, @BLtheP, & @BabyBilly .... I broke out my MX+ again and drove around finding out my speedo was in fact wrong. I really appreciate you guys bring this to my attention. I re-installed the Hypertech and now the speedo is correct. I am running it with a ratio around 1.201. I am not sure what I was checking in the past, but I might have put in the wrong numbers thought everything was OK and pulled the Hypertech thinking everything was OK. After running the MX+ today I was in fact off by around 12 MPH. Again, I appreciate you guys calling this out and making me check it again and putting the Hypertech back in.

 

The gear stuff can be completely thrown out the window for recalibrating speedo on a 3rd gen. You tires are 22ish% larger than stock (38/31), so that is why 20% worked. The Speedo also starts 3% fast from the factory (but odometer is correct), so when you only calibrated it 20%, your Speedo is now spot on as a result.

The only thing gears affect related to speed is top speed on autos. The autos have a driveshaft speed sensor that is obviously sped up by a regear. On a stock truck that has 5.29s, the speed will be limited to around 83mph. The larger the tire you install after that, raises the speed back up. Or, a tune can be used to set the programming limit high enough to no longer factor in.

Manuals don’t suffer this problem, I’ve had my 5.29 gears and small tire manual truck above 100 mph before with no calibrating whatsoever. All is well.

 

@caribe makaira By some chance do you know the part number for the connector on the other side? So if 90980-12557 is the female side what is the male side, do you know? I would like to make a T-harness and be able to reference all of the part numbers for everyone.

 

Also an update, I have been talking to @BLtheP as I figure out a good write up for all of the parts and more detailed instructions on the spoof mod @BLtheP prototyped out. I have also ordered all of the parts I need other than the T-harness material as I don't know the part numbers for these yet. I would rather not buy a 2Lo or another HyperTech harness and modify it. I asked some of the 2Lo companies if they would sell me just the harness or what the part numbers are. No luck asking them. Although Hat's off to black ops for responding to all of my e-mails and answering my questions the best they can.

 

Haven't had luck on the mating part number. I just found that Hypertech (and others) make a harness that can be modified.

 

I found this reference, but I can't find the actual parts at the links that were referenced in that thread.
https://www.tacomaworld.com/threads...d-gen-development.537810/page-8#post-18502754

After doing some digging I found them here.
Looks like:

• 40P025K-NH-F (40P025-NH-F-tr) - 40 pin female connector - Matches F13 - https://www.hi-1000ec.com/product/66
  
• 40P025K-NH-M (40P025-NH-M-tr) - 40 pin male connector - Matches F13 from the 4WD ECU - https://www.hi-1000ec.com/product/64
  
• 10P090-TS-F-tr - 10 pin female connector - Matches F12 - https://www.hi-1000ec.com/product/2806
  
• 10P090-TS-M-tr - 10 min male connector - Matches F12 from the 4WD ECU - https://www.hi-1000ec.com/product/2806
  
• F090-SMTS - Female Terminals - https://www.hi-1000ec.com/product/1335
  
• M090-SMTS - Male Terminals - https://www.hi-1000ec.com/product/1334

Everything can be sourced from here: https://www.hi-1000ec.com

 

Latest status, still writing up more detailed instructions and waiting on the T-harness... I ordered a 2Lo kit as it would come faster than the parts above.

• Got the T-Harness in - starting to work the solution today
• The write up is in decent shape, waiting to put the solution together
• Will share some parts while I go

 

I just realized after starting to wire everything up that I didn't understand nor read the wire diagrams correctly. Fixing the write up and re-wiring stuff now. Pins are grounded not energized to activate them. Off == open circuit On == Grounded circuit.

 

Latest status - the wire harness is done, I tried hooking everything up and it didn't work.

Currently:

• I have the manual t-case wired up to the 4WD-Hi and 4WD-Lo indicators
• I have the ADD and rear e-locker on their own harness, but the original plugs available
• I have come up with a 3-relay solution which @BLtheP looked over. We agree based on his original investigation that everything looks good for spoofing the ADD and the T-case only

Initially:

• All the 4WD dash lights came on when putting the fuse back into the 4WD ECU under the dash and starting the truck
• First: The rear elocker light was blinking
  • The rear e-locker will need to be spoofed if I use the 4WD ECU w/ e-locker as I have run a new wire harness for anytime rear locker
    • The elocker was blinking and complaining until I hooked the original elocker plug back in then this light went away, but the 4Lo light kept blinking with a complaint about 2WD and 4WD not working
• I checked all of the Ground and Voltage lines, they were all good. The voltage wasn't 12v it read something like 13.4v
• The relay(s) click on when I first start the truck

I think it will be easier to check all of the lines during the day light so I am done for this evening.

• I will try replacing the relays first
• I will re-check my 4WD-Hi and $WD-Lo indicator wires under the truck (they were working when I first checked them upon install)
  
• I will make sure the line(s) going to the relay pins are correct
• I will run each wire-line to make sure I didn't connect something wrong
• Next would be to check the grounds through the relays

If all of these things are good then I am missing something that needs to be spoofed. As of this evening I tried only the ADD and T-case together. Tomorrow I could also try hooking the ADD back up to its original wire/plug too and see if just spoofing the T-case works. So I guess still work to do. If I really need to isolate everything I guess I could splice my new T-case connector back into the original T-case actuator T4 plug. Then I can start isolating each item. Hopefully I don't have to do this part...

I am not ready to post my solution as it didn't work yet.

 

I can only comment on the one item I have some expertise with. The indicators on the Combo Meter. How did you connect to the indicators?

AND

It sounds like you did not go with the microprocessor.

 

Can’t connect to the dash indicators - the ECU handles all that all over CAN. Just have to fool the ECU with the appropriate grounds operated by the manual transfer case switches.

 

Know nothing about this manual xcase you speak of.

It is a little much to wire in the LEDs on the Combo Meter, but could be done if you like. See post#63.Anytime rearlocker

At one time I would have loved to see the schematic of what is being attempted, but for now I will concentrate on ARBs, both front and rear.

 

• I might still do the microprocessor too, not sure yet as I wanted to make sure the circuits I drew up are accurate and working.
  
• I did by two micro-controllers to test with and wrote the basic logic that would go into them, then I stepped back and went with the relays first to make sure my understanding of how everything should work it accurate.

• You can technically by pass the 4WD ECU and get direct access to the dash indicators but I didn't want to splice into those wires, going the T-Harness route and faking the 4WD ECU is what I am after first.

Initial findings as of this evening working with BLtheP over private messages (thank you). For some reason my 4WD-Hi indicator (Pin1 on F13) is grounded while in 2WD. This leads me to believe I either made a mistake at the T4 plug (T-case actuator plug), or wired something wrong on the T-harness I created. It is late here and raining, so I will take a look at both of these items in the morning and let you guys know what I find.

Please know I sincerely appreciate the help and the responses, thank you. Once I figure this out I will post all of the details of my write up for anyone else to have.

 

You can’t, there are no wires to the instrument cluster for dash lights. There are only CAN lines. The ECU tells the cluster when to light the lights, and then it does so.