Automatic Door Lock Issue -2011 4Runner
 

I have a 2011 4Runner that just started having a problem with the automatic door locks AND wireless key fob. It doesn't appear to be an issue with the actuators or the remote itself because I changed the battery in it when the problem first started last week. Here is the observed behavior.

When the key is in the ignition, my door locks operate normally. I can lock and unlock the doors using the buttons on the drivers/passengers doors. The key fob is disabled when the vehicle is running (normal).

I remove the key from the ignition and can lock the doors with the key fob.

I return to the vehicle a time later and the key fob no longer unlocks the doors. Manually unlocking the door with the physical key/lock and opening the door...the lock/unlock button does not function.

I place the key in the ignition and power the 4Runner up to the ON position. Lock/Unlock works again on the door. Moving the key to the off position and removing the key, I can then use the key fob. I can do lock/unlock with the key fob OR the door controls about 6 times before they stop working.

####################
I unplugged my battery last night to do a master ECU reset.

Thoughts I am having....it appears when the key is in the ignition, the electrical circuit providing power to the locking system is different than when the key is in the off position. Could it be that there are 2 circuits involved here controlled by a relay.... It almost seems as though a capacitor has enough power to lock/unlock the actuators 6 times before running out of power. That makes me suspect a fuse, but those I looked at so far, appeared to be good. Anyone seen this issue?

You don't happen to have a fridge in your truck, do you? They have been known to interfere with the receiver.

No fridge, everything's stock...no additional electronics. The problem just started last weekend. I'm the original owner of the 4Runner, which I bought in December of 2011...so it's almost gone 8 years without having this problem.

I'm hoping someone else has had a similar problem and found a solution.

I'm still having the issue....nothing changed. Does someone have a wiring diagram with the associated fuses?

I'm really thinking there are 2 different circuits here providing the door locks power.
One for when the key is on in the ignition and another when the ignition switch is in the off position. Can anyone confirm that? I'm not finding answers through Google.

How healthy is your battery? I would suspect bad relay if it was consistently having issues but it sounds like it only happens when not being charged by the engine.

There are two paths; one full-time and one via key == acc & on- I'd try cleaning the contacts of fuse 'ecu-b'.

Here are the wiring diagrams<--

I would say that too, but it's a new battery. I just replaced it 5 months ago from the solid Panasonic that came with it. (got 7 years out of that battery!)

I actually tried to lock my doors as soon as I powered the engine off coming into work this morning and the buttons were dead. I put the key back in the ignition, turned it to the on position without starting it...then off....closed the door and the doors locked. When I return, I'll have to use my key to enter the vehicle.

I'm looking for fuse ECU-B...

This is what my fuse panel looks like:
IMG_20190829_102648405.jpg - Google Drive

On the top left, I checked/reseated the 30A - 25A fuses on the top left and the two that are labelled DOOR RL and DOOR in the middle (25A/7.5A). I'm at work and don't have a fuse puller/needle nose handy.

Look at the engine compartment fuse/relay box. Big black box next to your master cylinder.

I had my fob stop working completely on a previous vehicle. I think it ended up being a blown relay but can't say for sure because it was a new model and had lots of Gremlins.

I ran home on my lunch break and went through the "Door" fuses again and reseated them all. I also went through the ones in the middle row and checked the ECU-IG No1 and ECU-IG No2 (which I assume is the same as ECU-B). Both of those fuses looked fine and were reseated....the issue remains.

icu-b fuse is in the engine bay box.

Thank you for the diagram. I'll check it out when I get home in another hour or so. I'm hoping I have some time to check this out...it really seems like it's a fuse the way it's acting... I certainly hope it's not something more complicated like a faulty switch. Intermittent stuff is so time consuming to track down without more access to the connectors and knowledge of where all the wires are.

It sounds like you have a bad door lock actuator. I've seen this mentioned on this forum and here is a good link:

Driver's Door Lock Actuator Motor Repair [step-by-step w/ pics!!]

and have lived through this with my wife's 2016 Highlander (similar design) having replaced both right side actuators with ~40k miles (one 3 months after the first).

You can buy a new OEM equivalent AISIN actuator on Amazon, by cross referencing the Toyota part number at significant savings.

What came out of the Highlander was identical to the Amazon part, both AISIN, both had the same part number. Difference was the new part had a big "3" vs "2" that was in the car. Hopefully this is a revision number and AISIN has addressed whatever the issue was that caused (in my mind) premature failure (likely the motor as described in the thread, above).



Good luck.

Have you tried the other fob when you are having this issue?
Fobs have been known to fail......

Have you tried the buttons on any of the other 3 doors when your having issues?
Door switches have been known to fail........

The actuators all work though. The problem is that they all appear to lose power within 10+ seconds of the key being turned to the off position.

Prior to that, the key fob and buttons all work. Once I lose the ability to lock the door with the key fob, the all lock/unlock buttons also no longer work. I can simply turn the key to the on position after that...and back off again and everything functions again for another 10-20 seconds.

I understand the switches could be causing the problem, but this screams of a circuit/power issue and not an actuator issue.

I checked the ECU-B fuse and it appears to be good. I reseated it and a few others that sounded like they may have something to do with the door locks. All had clean metal.

I'm really tempted to take this to a dealership just to have them fix it, but don't like their billing methods...I'd like to work this out myself if I can so I'm not just throwing money away.