4WD not engaging and light not working

Hey everyone, so I've combed through a bunch of threads and videos on 4wd issues. I tried a few things but nothing has worked thus far. I'm just posting this to start small and working my way to the bigger issues and see if anyone has additional input.

Info

1. 01 Tacoma 3.4 Automatic with the auto push button 4wd, manual shift 4low system. 4wd worked like a charm 2+ years ago when I would regularly drive it in snowy conditions.

2. Truck hasn't seen 4wd for almost a year. Before that it was acting up. The light would blink or not turn on or stay on at the wrong times. 4wd would eventually engage but be very slow or cumbersome to disengage. I brushed it off as me not using the system as much as I should. Once I was using it regularly, I figured it would start working normally.

3. I recently tried to engage and get the 4wd operating again with winter coming up and here's what I know...

- No 4wd light whatsoever - no blinking or anything anymore.
- 4wd never engages. Front driveshaft does not even lock up.
- No enagagement/movement noise from the transfer case actuator.
- Tapping on the motor didn't solve an issue, all connections look solid.
- 4wd fuse not blown and I even swapped it to be safe.
- I can hear the relay click when depressing the 4wd button. Other than that, no other action.
-elocker light and operation works as normal (has grey wire mod).
- Does go into 2lo but it does not force the 4wd light on with or without the button depressed.

My questions are...

1. Are there any other tests I can do? I've watched a video where a guy hooked up the transfer case actuator to a car battery and was able to test the motor.

2. What are the smaller parts I should start with before replacing the whole actuator? 4wd ecu? Sensor? Switch?

3. Best place to order an actuator from if it comes to that?


Thanks everyone.

 

I had these symptoms last month and it was a failed position sensor on the T-Case. $25 for a new one and five minutes to do the swap. I think it took me longer to find my 27mm socket than to do the actual fix.

First gens use this same part number for the reverse-gear sensor and position sensor on the e-locker, and all three of them have failed on mine over the past year. Maybe I just got lucky but I didn't even bother with other diagnostic steps because it's such a cheap and easy thing to try first. Certainly cheaper than a new actuator, yeesh!

 

Check out the following...

 

That was my thought. Go with the sensor first as it sounded like a culprit and probably the easiest fix. Thanks!

 

Great, thanks!

 

It is really important to engage 4X4 and get in a few miles regularly. I think 10 miles/month is suggested. Twenty years ago, we had a Jeep Cherokee that my wife drove. 4X4 wasn't used regularly and stopped engaging. The lubricant in the hubs had hardened from non-use and would not allow the hubs to lock. After the hubs were disassembled, cleaned, re-lubed and reassembled it worked fine.

Since then, I've made it a priority to get in a few miles in 4X4 regularly. I may only get in 2-3 miles some months, but as much as 200-300 other months and I may occasionally miss a month. But I do get onto a gravel road and engage 4X4 regularly. Haven't had an issue with 4X4 since.

 

That was the plan but unfortunately I was out of the country for the last year and the truck was in storage.

For reference, looks like the sensor part number is 8422212010.

 

Woof! $85 at my dealer with online discount. Part number 8421052050 (backup switch) is $36 and they interchange just fine. I do see both on eBay for around $25 though.

I used OReilly / Masterpro # MPI 2-8950 to replace all three. Maybe I won't get 20 years of service out of them, but at $25 each I'm not too worried.

 

Got it thanks. I see oem ones on ebay for just over 50 bucks. Just deciding on if I should go oem or not.

 

Do you have a vacuum hose going to the actuator? I attached a picture blow air into the one vacuum hose and should work some time they get plugged up happened to mine has worked ever since. The one I’m pointing to in picture is the line you need to blow in if that don’t work blow in the other one

 

Try that before ordering any parts it a free fix air costs $0

 

I have the j shifter no button but I’m pretty sure there should still be a vacuum hose to actuator

 

"Look"? Did you disconnect and clean them with electronic contact cleaner? It's a simple thing to do. The connectors can get dirt and water in them over time and sometimes just need to be cleaned.

The electronically activated 01+ (even j-shift) don't have vacuum lines to the front diff actuator. There are breather lines though. Easy to get confused.

 

That’s 100% vacuum lines and they go into a solenoid

 

Or if they aren’t what ever the hell they are lol it worked to engage 4x4

 

I had the same issue about a month ago, turned out my 4wd actuator in the trans went out completely and the entire assembly needed to be replaced. No engagement, immediate 2wd/4wd mode change failure light on dash. Dealership did tests on the trans actuator itself and found the motor assembly to be the failure.

Luckily under warranty ($100 deductible for the job) but the 4wd actuator replacement in the T case is a $2800 job from the dealership.

 

Model year makes a big difference. At a certain point, even the j-shift had an electronic ADD activator.

 

1996 3.4 manual tacoma

 

OP has an 01, so suggesting he try clearing the vacuum lines is unlikely to work for him, as he'll be "clearing" a breather line.

 

never know till you try it take 2 mins and is free . Worth a shot