Cruzer's Re-Build for the Rubicon

That would be mind blowing except for the fact that she drives my truck 5 days a week now. She’s noticing things How come your vents don’t work? Your truck is squirrelly on the freeway, I don’t like it. Did you know your windshield is cracked? Did you know your speedometer is not accurate?

 

I’m glad my old lady doesn’t want to drive mine
Lol

 

Oh she hates driving the truck but her commute to work is 12 miles round trip while mine is 70,

 

Ew!

 

Riiiiight?

 

I used to drive 3-4k a month(in a company truck) it suuuuuuucked!!!! And In some of the same traffic you do! I started to take side streets to free my mind

 

It's time for another vehicle. Or, best case would be to get her on a bike. Maybe an E-bike

 

So I bought a 16 relay board



This weekend I will attempt to hack the 4WD ECU and the Transfer Case actuator. The goal is to trick the truck into thinking it's in 2WD while I manually shift it into 4WD.

Why? My truck has not been shifting when in 4LO, it's stuck in first gear, but shifts fine when in 2WD or 4HI. Also, when in 2WD everybody here knows that the Tow Haul Mode button gives the truck some extra oomph when the ECM shifts the throttle angle more open by a few degrees. However, the Tow Haul Mode is disabled when you go into 4WD.

I will hopefully be solving two problems at once 1) shifting issue in 4LO and 2) torque issues when crawling big obstacles.

Through an Arduino the relay board will be used to disconnect certain pins on the wire harness between the 4WD ECU and the Actuator so that the actuator is unable to notify the ECU, via internal trigger switch position changes, that voltages have changed. I will also configure it so that the relays apply power to rotate the actuator motor that shifts in/out of 4HI/4LO. There are still a couple of unknowns that I need to figure out but won't know until I start chopping shit.

 

You sound like a mad scientist

 

Sorcery!

 

Super cool! I love the initiative.

 

Here's my initial wiring plan. I just need to figure out how TL1-TL4 works with the actuator motor (TM1/TM2) and the Solenoid Coil (SCC). I want to automate as much as possible so I'm hoping that I can use TL1-TL4 as a trigger to stop applying voltage to the motor and coil. Won't know until I get in there.

 

looks like you have been and still have some signal chasing to do.

 

Cruz just ignorant curiosity, are you just transferring signals or actual power? if power I understand the relays but if digital signals why not a smaller pcb utilizing and gate ICs and remove the potential for sticking relays

 

The relays are definitely needed to operate the motors and coil. I could probably use ICs for the other pins but this board is the quick and dirty version for me. If this works, then I may have to pick your brain at T2S to figure out how to shrink this

 

From "how do I keep my beer cans from rattling in the fridge" to "i'm designing a computer to control my transfer case". This thread has EVERYTHING!

 

Messing with the 4WD ECU turned out to be a lot harder than I expected BUT I am making progress.

Turns out that whenever you disconnect a single pin, basically when the 4WD ECU can no longer detect what's on the other end, it will flash you 4HI/4LO all day long and won't let you change TC modes. I spent a lot of time gathering data, collecting voltage, current and resistance, at different stages of the transfer case (2WD, 2WD>4HI, 4HI, 4HI>4LO, 4LO, 4LO>4HI, 4HI, 4HI>2WD, 2WD; pin connected, pin disconnected, etc.) Found out that the TC Actuator uses diodes to regulate voltages. Anyways, long story short, I've figured out how to trick the 4WD ECU into thinking it's still in 2WD mode on 7 out of the 10 pins. The remaining 3 pins required me to order more parts so I'll be at it again next weekend.

 

9 out of 10 pins tricked! I'm thinking I can ignore this last pin to SCC. So I'm moving forward. I'm writing up the code to create an app that will change the modes. Pretty basic, looks like this. Hoping I can do a test drive tomorrow.

 

What does manual mode do?

 

That's when relays are triggered prior to ignition start to trick the ECU that it's in 2wd. When I manually change to 4hi or 4lo, the ECU will still think it's in 2wd.

 

On the road somewhere

 

Driving through

 

Hahaa the student driver sticker. Well done

 

Careful who is behind you at pit stops in Sedona………