E-Locker/4WD coming on randomly? Please Help!

Just bought my first Tacoma, it's an 05 with about 160K on it. After driving for about a month I noticed the tires were chattering on pavement when I made sharp turns. No lights on the dash at this point.

A few days later I noticed the Rear Diff Lock light was on while I was driving, and after pushing the locking button the chattering stopped. I know it's not supposedly possible for the Elocker to engage unless the vehicle is in 4 low, but this happened in 2 high!

After that the 4WD drive light started flashing at me, even though the selector dial was on 2 High. This indication comes on or off depending on the truck's mood. Now, the Elocker is stuck in the engaged position (with no indication on the dash) and pushing the button has no effect on the chattering of the tires.

My mechanic sounded skeptical and my guess is he thinks it's an ID10-T error (and i'm sure many of you do too) However, it's hard to get pics as this happens intermittently.

Is this a known issue with the 2nd gen trucks? Any threads you might refer me to? I scoured some older threads and found related topics but nothing quite like what I have.

I'm not driving the truck until I can at least get the Elocker to disengage... My first thought is to remove the Elocker from the rear axle, decouple the locking mechanism manually, reassemble and leave the cable unplugged to avoid it engaging again? I have also already checked relevant fuses under the hood and under the steering wheel to no avail.

thanks for reading, and thanks for any insights you might be able to share.

 

Are you the original owner of the truck? If not the previous owner may have done the e-locker any time mod, and you might be having a short somewhere within the system. I haven't done this myself though I do plan to undertake it in the near future, there's a correct way and an incorrect way and chances are if somebody's messed the wiring it was probably done the incorrect way. If I remember correctly the wires are behind the glove box, I would start there assuming everything else checks out.

 

I just bought this truck a few months ago, and have no idea what the original owner did with it as it was from a dealership :/ Now that you mention it I do hear a clicking coming from behind the glove compartment when the 4wd cycles, I'll try to have a peek behind there and look for scorching or non-factory splices if I understand you right? Thanks for getting back to me Key!

 

Yeah to do the locker anytime mod you have to cut and splice some wires and install a relay, if you're hearing clicking over there that's where I would start.

Glove box comes out stupid easy.

Open it.

Slip a finger beside it on the RH side and disconnect the soft open shock by pushing it off the nipple.

Squeeze the sides of the glovebox in towards each other to allo the srop tabs to pass the glovebox frame and pull it "open" further.

Lift up at the bottom of the glovebox and it will pull off the hinge.

Should be able to see the ECU and 4x4 controller on the righ side by above the kick panel to the side of the HVAC blend box.

Now is a good time to change your AC filter too.

 

Faaaaannntastic. I'll try having a look this afternoon and get back with some pics, more to come! ...and thanks again

 

Keep us updated, if that ain't it we can try something else.

Another thing to do, you could always take it in for the frame replacement if it hasn't had one yet and still qualifies and then say ever since you got your frame replaced the locker and four-wheel drive has been messing up and let them fix it...

That might be slightly less than ethical though...

 

Allllll right... after digging into the dash I'm not seeing anything that looks out of place, or signs of scorching, but who am I to say? I checked to make sure all of the harnesses were fully seated, and unplugged a few to look for signs of a short but no luck. Do you all see anything of note?

 

OP, the 4WD computer (two connectors) lies above all that and back toward you, slightly to the right.

 

Yeah that all looks pretty normal but check where Taco'09 said to as well.

If there's nothing there then I would crawl under the truck and start tracing the wires from the locker back and see if you can't find any rodent damage.

 

Ahhh I see now after a quick google where it's located. Since the 4WD and the Elocker are both acting up, would it be likely that the 4WD computer itself might be at fault? Any experience on swapping these out? I'm wondering if I could find a cheap one at a local junkyard to try out if it's not too scary to attempt. I'll post some pics later this AM of that area.

 

Eh... Toyota's computers are pretty dang reliable, only thing I could see causing it to fault would be water damage, I'd pull the connectors and check for fine silt before shelling for a controller unless you can get one really cheap. I suspect either rodents or abrasion has caused a short of some kind.

Personally I try not to throw parts at a problem if I can help it, a little diagnostics can go a long way.

I recall someone some time ago having issues with the 4x4 and it ended up being a broken wire or two in the e-locker harness where it flexes when the suspension is at full droop.

When did the issue start happening? Any particular environmental conditions? (Rain or off-roading?) Or did they show up within a few days after such?

 

hmmm good question. I haven't noticed a connection between rain and the behavior of the issue.. in fact the truck has been in the garage for the past week or so, and the 4wd indicator randomly came on last time I started it to put it on ramps. Turning the vehicle off didn't clear the indicator, but starting it back up later in the afternoon did. Good advice on the 'parts shotgun', I tend to take it out too often and not diagnosing enough... maybe i'll find something after I get the work emails cleared out and get a chance to investigate now that I know where to look! I'll also try chasing the wiring from the Elocker back, that sounds like it's possibly the issue..

 

Here is the 4WD computer.. @Key can you tell from this if it has the LockerAnytime mod from this pic? All the contacts appear OK. Looks like it's time to chase my way back up from the Diff lock unit itself and look for damage if I follow you all correctly.

 

It doesn't look like its been moded. Here's the link to the locker any time mod.
https://www.tacomaworld.com/threads/locker-anytime-mod-for-dummies-2005.353724/
The arrow is pointing at the 4WD controller

and it will look something like this when its done

 

Thanks JSI! Time to trace some wires I guess

 

Be sure to check wiring to other 4WD system components. Transfer case, front diff actuator etc. I recently had what ended up being a rodent problem on an AWD car I own, amazing what is connected to what and what happens when a family of ground squirrels takes up residence deep up inside, behind the fender liner. ABS, brake pad wear sensors, wheel speed sensors, etc. Little bastards. Have you tried pulling any codes?

 

Also check the sensor and breathers on the front diff ADD block and the sensors on the transmission and transfer case.

They are 24mm hex with a plug coming out of them.

 

thanks for the continued feedback, all! I'm barely even a youtube mechanic at best, so had to do some research just to find out what terminology you were using.. the ADD was new, and looking through some other threads I was able to educate myself a bit. But to answer ajpogosa, i haven't tried pulling any codes as I don't have a code reader. A while ago I had the free scan done at Autozone and I ended up finding out my left CAT was going bad.. i'll try to dig that up to see if that scan had anything else on there.

Key do you have a thread you could link me to showing how to test the sensors? I'm able to at least use a multi meter but anything beyond that might be something I need to take in. Fortunately I have a mechanic I can loop in if I just can't get there.

All that being said i'm really enjoying learning from you more about my Taco and cars in general and hope we can track this down together!

 

So today I was able to pull the Elocker from the rear differential and wanted to start there to check the wiring and any connections that might have come loose, then trace the wires looking for shorts. Upon pulling the locker i was really surprised how much debris found it's way on the inside face of the unit. I carefully put a latex glove inside the opening to the differential and began cleaning the area to get a better look at things. When cleaning the locker itself and getting the road grime off of the electrical connectors this small black tube just slid out of the Elocker housing. It looks like a vacuum tube, but i'm unsure of what that would be doing there if the locker is just an electric motor that advances and retracts the engagement gear? Could this hose be related to my issue somehow? See the pics below. Apologies for the quality in advance.

 

here are some better pics of the inner face of the elocker: