4wd System Operation & Help Thread

Have you tested the 4wd detection switch (should have continuity through it when the little ball on the end of the switch is pushed in).
You could also still be a tooth or 2 off on the gear.

 

Yea unfortunately everything is going to fully electronic, todays generation just want to push a button or flip a switch and have everything happen for them instead of pulling a lever.

Although I don't really see too many issues with fully electronic 4wd systems, much better than the early vacuum ADD systems that many manufacturers used and Ford still uses.

Many of the problems that happen to electronic systems are from lack of use and on Toyota's from the vent lines cracking or falling off the actuators.

 

I haven’t tested that individually yet, I’ll go ahead and give that a run once the truck cools down. Having the truck as my only daily makes things so much more annoying trying to figure things out

 

Switch is good. I feel like I’m getting closer, so that leaves actuator timing? In my mind that makes me think to get the timing right, I could shift it by hand to 4x4 and use the switch to tell me when In the proper position from a continuity test? Or am I over thinking something

 

I've yet to have one apart but reading about others doing it it seems alot of trial and error is involved, you want the contacts of the drive gear plate to line up with the contact plate as shown depending on the position the transfer case is in.

 

I got 4 hi back!!! 4 low isn’t working but I’m taking this as a win. 4x4 sensor had an internal wire brake near the plug, I just so happen to have a spare at my disposal and got it quickly twisted together and boom I have a 4x4

 

Nice, sounds like we're almost there.

 

So, now all it is is 4low will flash and beep but not engaging

 

Are you fully depressing the clutch when trying to engage 4lo?

 

Yes, dead stop, neutral no rolling foot to the floor, just beeps

 

Need to make sure it's getting a clutch signal, the beeping typically indicates conditions aren't correct for a shift.

 

I lied. I’m just dumb lol. Floor Matt got in the way

 

So is it all working correctly now?

 

Yes, thank you all so much for the help. I feel like I finally got my truck back, best part is I just came back from a deployment so I get a full year with the truck and can actually use it again, torquey lil bastard on 5.29’s in 4 low

 

Nice glad you kept at it, got it fixed, and came back to tell us, so many people ask a question, get some answers, and never come back with an update.

 

First of all, thanks for all of you taking the time to share what you know about this system. I would be paying someone thousands to figure this out without you guys. My truck is a 2007 V6 DC OR with 110k. I have both lights blinking constantly. When this first started the blinking was intermittent. When the lights weren’t blinking the four-wheel-drive would work perfectly. Then the next day the lights would blink and the four-wheel-drive will not work obviously. I found the deteriorated vent line and cut off the bad part. No Joy. I replaced the whole thing, still nothing. I pinned out the 4WD ECU and this is what I got.


This telling me that I have a bad transfer case actuator. Or a corroded TL1. This would make sense because if I select 4WD I get nothing, no clicks behind the dash, no actuators moving, nothing, just blinking lights meaning the system is locked. Right? Your thoughts would be greatly appreciated before I start throwing parts at it. Thanks

 

I just recently read in the manual that you should actuate the four-wheel-drive system for 10 miles once a month. I thought I good for doing it every couple of months for a couple of miles. Guess not…

 

These readings were taken in 2wd?

id do two things. Remove L4 switch and ohm it out, the seal can fail for them and cause oil to get into the switch electrical assembly. Repeat voltage checks again. If you most likely the transfer case actuator has a gummed up contact. You can remove the cover and clean it up and reinstall and try and take the readings again.

 

Both, the switch position was in 2H for the 2H column and 4H for the 4H column. I hope that makes sense. I’ll pull the 4L switch tomorrow and report back. What readings should I get back for a good switch.

 

gotcha, yeah I see now. I guess what I was asking was did the truck actually go into 4wd for that second scenario? The 4L switch should be open circuit across it and then if you push the detent ball in it will be a closed circuit, exercise it several times to make sure you get consistent results. And check for oil in the connector end.