Let's see your FJ case swap

You going FJ tube/axle or is there some other actuator replacement I'm unaware of? I didn't like the idea at first but after looking at the guts of one I'm struggling to think of how enough axial force would be generated to back drive the gears and motor unless there was some gnarly wear on the splines or something like that..

 

Yeah, FJ tube

 

If FJs can do it, why not us? Parts are the same

 

Yeah it's the way to go if one isn't thinking about keeping the actuator alive. I liked 2-Low a lot in my 3G, trying to not close off that potential option.

In that note, I still don't have a concrete answer on twin sticking the full time case, I futzed around a bit and couldn't get the diff lock rail to move to the unlocked position when in neutral or low - but I was trying to do this with an improvised setup while on the trans jack. It felt like a pretty firm "no" though, so I am erring towards there being some sort of interlock. I'm getting time critical so I just need to focus on getting it back on the road with everything else going on.

 

Maiden voyage today. I ended up getting a deal on a brand new front shaft on eBay a while back, rebuilt the salvage yard shaft with Spicer parts, and got both of those on yesterday. Today was dropping it off the stands, torquing all the new suspension bits, and doing a quick string alignment. My attempts at the paperclip VSC reset were unsuccessful, so some investigation due there, but couldn't help but take it out for a few miles.

Can't quite stomach taking this thing in to the salt quite yet, but my road is still all hard pack snow in spite of recent sunshine and higher than recent temps, so I got a few miles in and some short stints at up to 60 MPH. No drama thankfully, everything just worked (outside of the aforementioned dash lights).

The difference between locked and unlocked 4WD is somewhat subtle but noticeable; even with the snow, you can detect the driveline binding when it's locked. My harshest test in this quick drive was my driveway, which is also packed snow and inclined. I left it in unlocked 4-HI and stopped on the steepest part, wondering if it would slip or one wheel peel with the VSC defunct, but it just crawled on up. Even tried again with it rolling backwards a bit and same story; so I guess the Torsen must be doing its thing.

It's definitely added some time, cost and complexity to my project; but initial impressions are that I'm going to be very happy with this swap..

 

Unexpected free time this evening! Back at it.

Techstream is showing I have a C1268 malfunction; Google seems to be telling me this is a transfer case actuator error. In the data list, my L4 switch is functioning per the data list.

My 4WD computer is disconnected, the transfer case along with the actuator is gone (obviously), and the front ADD is disconnected.

Other things: the zero point for steering is correct/where it should be, but an attempt to clear memory and reset via TS this time also did not work (two attempts).

Only thing I can think of is I left the 4WD selector on the dash in 4-HI after I set the ADD. I don't recall if I powered the ignition on after disconnecting the actuator, but before disconnecting the 4WD computer; but I was under the impression that once the 4WD computer was disconnected, it wouldn't care about any of the actuators (so this might not be true?).

EDIT: verified the sensors were in the right place (red w/ stripe on right, yellow w/stripe on left), and disconnected both sensors on the case. Switched selector to 2WD. Left battery disconnected for ~45 min to reset; error persists. Does the 4WD selector on the dash need to be pulled as well?

EDIT 2: left sensors disconnected and selector in 2WD; reconnected 4WD computer. VSC/ABS lights are now off; but have flashing 4WD and Low Range lights. Disconnected the 4WD computer again, and the VSC/ABS lights are back on.

 

What doesn't unlocked and 4Hi mean? Do you have a front locker?

 

T-case in full time mode (or 4-HI with the center diff unlocked).

 

This is definitely one that I'd ask @Dm93 for where to look next. If the 4x4 ECU is unplugged, you shouldn't be getting 4x4 error codes so me thinks whatever isn't allowing zero point calibration to occur with the paper clip is triggering the error code. Or vice versa. Thanks for keeping us posted thus far! Congrats on most of it being done. The rest is just details.

 

Code setting criteria isn't all that clear but I'm thinking maybe it sets when it sees a L4 signal but not a 4wd signal.
I would have to do some experiments to know for sure but I'm thinking the sensor supply voltage is being provided by the 4wd ECU, with that not present the L4 signal isn't correct.

 

I think the zero point calibration may have actually gone through, but this error is keeping the dash lights on. The fact that the lights go off with the 4WD computer plugged in supports this I think, but also I believe I had been showing about 1.5 degrees off on my steering wheel after the paperclip attempts, but before the clear/cal via TS, and now it's at 0 degrees. But hard to say. Down side of doing everything at once I suppose..

 

Could this be simply a bad sensor or wiring thing on the 4WD side? I didn't see a cell for that sensor status in the TS list, but maybe it's in a different menu (I'm still a rookie there, only have it due to previous 3G tuning). This would be an easy multimeter and/or jumper wire diagnosis though.

 

Certainly easy to look, it's in the ABS data list. I'd take a look at what they are reading first and see if I'm on the right track.

 

Can't head to the garage till tomorrow, but is that from the data list? I have the ADD physically disconnected; if it's looking for a 4WD signal there then it's not going to find it in my current state, which could be the problem?

 

Yes, ABS data list.

That's not how it works, with the truck in 2wd the 4wd (ADD) switch is open (12v). Same thing with the L4 switch.

I believe the 12v pull-down signal comes from the 4wd ECU, with the ECU disconnected the circuits would essentially be floating if that makes sense.

 

I think I am getting it, but my brain is partially asleep already so all bets are off. I'll try to get back on this tomorrow evening. This is a full time case if it makes any difference, no 2WD position but assumed unplugging 4WD plug would have mimicked that.

 

I haven't kept up with this, so you have an AWD transfer case no 2wd or L4 positions?

 

Forgive me for answering Dm93, but wanted to do so to help your wheels turn tonight. He's got the FJC AWD case. H4 unlocked, H4 locked, N, L4 locked.

 

Ah ok, so as far as the ECU's are concerned we will still be using a 4wd and L4 input for those modes?

If so I'm thinking we could hook IND1 to ADD and IND3 to L4 at the 4wd ECU and use the wires under the truck to connect to the switches, in theory that would provide voltage to the circuits through the indicator lights and allow the lights to illuminate when the respective switch is grounded at the transfer case.


Srry I don't tend to follow swaps much as it doesn't interest me too much although I seem to often get consulted when the electronics don't behave as expected

 

Shots fired!

It's worth the abuse since I'd say you're the most knowledgeable, helpful guy on this forum when it comes to electrical systems. Thanks again for what you do!