2X 4wd Dashboard Fireworks

Howdy all,

Feel like I've read a few country miles on here about this topic. Switch from 2H --> 4H/4L, blinking lights, no engagement.

2015 TRD Sport

It's been like that for about 18 months and I finally got the fire to do something about it. Started with the ADD since it seems to be most common. Crawled under there and discovered the nipple for the breather tube was long gone and the hose was just dangling. Aha...thought this would be simple!

Ordered a new actuator, spent a Saturday morning putting it on, waited for the gasket maker to cure, filled with gear oil the next day. Drumroll...still same problem!

Feeling more than a little defeated, I took it over to a local mechanic. After a few days of holding my truck hostage with zero communication , they estimated that the 4WD ECU was bad and that it fried the new actuator.

Has anyone experienced a failing ECU make the ADD go bad?

They quoted me $1450 out the door to replace the ECU and actuator which seems about right? They insist on using only OEM parts, which I understand since they warranty the work for 25k.

I had them order the parts to do the work next week, but I'm just putting out feelers to see if I'm possibly being taken for a ride on this and could tell them "I'm good."

Thanks for any opinions!

 

I'd get it out of there and find a differnt shop or get a meter and some backprobes and test things yourself.
I haven't yet seen anyone have a failed 4wd ECU, not to say they can't fail but it is extremely rare.
Check out my thread below, we have helped quite a few people resolve 4wd problems several with no parts required.
https://www.tacomaworld.com/threads/4wd-system-operation-help-thread.742420/

 

Yikes. I’ve never seen an ECU go bad, very rare id say. The likelihood of having the actuator and ECU bad are even more rare, sounds like the shotgun approach on your dime. Leave that shop immediately.

did you install an oem front actuator? The dorman ones are known to be DOA or last only a short time.

 

Welcome to the Forum. What the previous two members said. Read through that thread and the one below. A recent poster had a successful outcome with a very cranky system. Not the same issue as yours, but very educational. Cancel your appointment and don't go back to that place. Good luck
https://www.tacomaworld.com/threads/stuck-in-4x4-low.556001/#post-28469057

 

Adding a conclusion to this story. Followed my own intuition (and advice provided here) and took the truck for a second opinion.

Just a call that there was bent pin in the electrical connector for the ADD. I guess that was my doing after I replaced it and, in my frustration, didn't both to check it.

There's no doubt the first shop was just trying to create billable hours on me and they'll certainly never see me again! Conversely, the second shop became my go-to mechanic!

 

I did use a Dorman replacement. May be a hard lesson I have to learn down the road, we'll see. I'm keeping the old OEM ADD and will fuse a new breather tube connector on it if push comes to shove some day.