4wd problems starting to just throw parts at it

Ive been battle this typical tacoma 4wd problem (flashing lights) for months. No shop motus scanners can seem to access the 4wd computer and I was wondering if anyone had one laying around I could buy or borrow to see if thats my issue/ I know alot do the fj case swaps but yeah i dont want to do that. thanks in advanced.

 

I just got done reading through some threads about fixing the actuator contacts in the front diff.

Apparently the contacts just rest on each other through spring pressure, and when that isn't enough the actuator loses continuity and can cause problems. Might be a good place to start if you haven't looked already.

 

You should post in this thread https://www.tacomaworld.com/threads/lets-see-your-fj-case-swap.455278/

There are lots of folks in there that have unplugged and are not using their 4wd ecu's. Maybe someone will send you one for cheap? There are lots of great folks on this site, just a matter of tracking them down!

 

Yup I literally have done and checked everything to find the issue pulled all the stuff apart. Just gave up and brought it to the shop for them to deal with it. Hopefully someone with one will see the thread and take pity on me lolol we shall see

 

OP, there are some good factory diagnostics for the 4WD system and all can be done with a VOM. If you want, send me a PM and I'll send some things to you. I may or may not see it if it is in the thread.

 

Just encountered this issue yesterday and did the “fix” on my ADD actuator. All-in, it’s not a difficult fix at all.

What others have said about the part is certainly true... piss-poor soldiering job at the contact points is the culprit. Here’s a pic of what mine looked like (contact points are circled):



After beefing up the soldier on the contact points, the motor that engages the fork to shift the 4wd collar spins like a top

I found this quick video on YouTube that served as a great guide on how to perform the repair:

https://youtu.be/ZJESG91GbCQ

Im waiting for the permatex gasket to cure (24 hrs purportedly) before I refill the front diff with fluid and test it out, but this should fix the issue.

There was a TSB out for this issue; unfortunately, I’m the second owner of my Taco and the first owner didn’t get this repaired before the warranty was up.

 

Thanks man. Yeah like I said I did all of these already. The issue goes deeper than that sadly.

 

Sorry to hear about that man; it sucks. I’m actually in the same boat... slapped mine back together yesterday and... nope, the issue persists. I bit the bullet and took my truck into the stealership today as I don’t have a scissor lift, jack stands, or anymore time to eff around with it.

On my quest scouring the Internet forums, I happened upon this internal Toyota Tech document related to the issue. If you have the time, jack stands and a multimeter, this should help you pinpoint the issue.

Good luck with the repair and I’ll let you know what the stealership says about mine.

 

Its looking like the motor in the front ADD is slowly failing. jumped it over with battery and leads and yeah it sounds like its dying out. def not the sound of a healthy motor. will update again when i can confirm

 

If you intend to use your old actuator, be sure to bend up those three prongs that protrude from the gear wheel so they make contact with the connections on the other side of the housing... I think that’s what got me in the end and my DIY repair would have worked had I done that.

 

well doesnt look like the front ADD was the problem, got a new one of them on, and now gonna do the transfer case actuator with a junk yard case that still has the motor on it (with a warranty lol). If that doesnt work thats it im done its a piece of shit and doing the FJ case swap.

 

from what I’ve found, that is the easiest and most consistent fix to these problems. Sadly if Toyota would have just offered it to the Tacoma in the first place, could have saved us a lot of head aches. But people prefer the flip of a switch rather than the shift of a lever nowadays.

 

Just though I’d share that I took my Taco to the stealership to perform this repair. $1,100 out the door (complete and utter fuckery), $500 some-odd dollars for the ADD actuator, and the rest was labor and taxes. Best part, it worked for 4 days, and this evening... yep, right back to not working again. This issue sucks!

 

Those are some lazy people. I think most people that actually use 4wd would prefer a manual lever.

Hope OP and other get it figured out sooner than layer

 

well both actuators were replaced and still doesnt work...pull the 4wd ecu apart hoping to find something burned up but nothing there either. Ideas? both actuators can be jumped over with 12vdc direct to the pins but nothing on board works. Used to be able to lock it up by the switch with a scan tool hooked up and the truck not running ( weird right) now that doesnt do anything either. Also checked the grounding block on the passenger lower side footwell and all those were cleaned and secure as well. So whats left? prob not doing an fj swap ( dont wanna)

 

I just replaced my ADD Friday. I am not an expert but did you check the 4 wheel switch?

 

yeah someone is sending me a known good one so ill try that one when it shows up. Im not good enough with a meter to be able to bench test mine so yeah lol.

 

Someone helped me with testing those sensors today and it’s relatively easy setting your ohmmeter to the continuity mode. Then connecting to the two pins and pressing down on the sensors detent ball to see if you have continuity in the sensors. I am currently in the same state as you although both actuators I used for replacement were junk yard. After Toyota said both of mine were bad. I am suspicious of my wiring harness at this point but as others say FJ case is the only firm solution. Will let you know if I find a solution to this problem and bump.


When you mention your testing a new switch are you referring to the cab switch? Do you not get any response when flipping across the two drive modes? If no response that’s a good attempt. Could try unplugging the ECU for a bit too to allow it to reset. After driving sometime on my way for Toyota to look was the first time it stopped blinking. Now it’s “sticky” blinks but I can generally get it out but never becomes solid still. Huge PIA. Here’s my thread if you want to watch it for future solution if I find one too. https://www.tacomaworld.com/threads/another-4wd-blinking-thread.698555/

 

Yes. the switch in the cab.

 

Put in a new t-case. Did that with my old truck when the actuator got drowned and refused to work again (not the front ADD).

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