Factory e-locker misbehaving

2009 TRDOR, no mods to the 4WD/locker system.

4LO no problem. Hit the RR LOCKER and I can hear the dash click and I can hear the actuator in the back slide. Dash light for the locker blinks.

Haven't used the locker in a while, noticed a few months ago it was inop when I tried to go whip some shitties in the snow.

Slow roll/turn wheels/reverse/jiggle/mallet taps to the actuator, still blinking.

I'm thinking A) the pinion on the actuator is toast, or B) the sensor for the lock state is bad, either the sensor or the wiring somewhere.

I'm guessing the next diagnostic is to engage the locker with the rear up on stands, put it in neutral, and try to spin one wheel to see if the other matches? That would tell me that mechanically at least it is locked and that the issue is sensor/wiring/4wd ECU?

Any insight or suggestions would be great.

 

The locker isn't the easiest to diagnose due to the limit switch voltages not staying on when it isn't active but it can be done.

When the locker is operated RLY1 should be at 0v in the unlocked position and change to 5v when the actuator is in the fully locked position.
RLY2 should start at 5v in the unlocked position and go to 0v in the locked position.

RLP is 12v when the gears are physically unlocked and 0v when they are physically locked.

If you have a DC amp clamp you can also put it on one of the motor wires (M1 or M2) and see what the current is.

I don't have alot of info about the locker here but I do have the voltages listed in the spreadsheet.

4wd System Operation & Help Thread | Tacoma World

 

So if I am reading this right, I should be able to backprobe RLY1/RLY2/RLP at the ECU end of the harness, and watch their states as I chucklefuck with the dash switch. RLY1/RLY2 should swap each other 0v/5v IF the limit switch is reading correctly inside the locker assembly. Would it be a terrible idea to stick them both on a meter and just wait for the indicated volts to flip positive/negative?

Where is RLP physically located? I believe it is functioning correctly because I can hear the locker actuating, but it would still be good to know, in case I need to probe it or test it. Is it even field replaceable or is it sealed inside a black box (the ECU or something?) and needs to be done one a bench?

Edit: it also looks like M1/M2 should pulse to move the pinion in the locker assembly, and probably pulse opposite polarity to go the other way? This would be controlled by the limit switch via the ECU, and correlated to the pulses for RLY1/RLY2? Whatever, I'll worry about that once I do the basic checks... I hope I don't end up needing two or three meters at a time to find out it's time to go to a mechanical actuator and ditch the 'trons.

2nd edit - woah man that post you linked is something else. That's GREAT documentation.

 

Yes.

Never tried that so I don't know what kind of reading you would get across them but if you had more than one meter you could watch both at the same time.

RLP is the physical switch on top of the actuator that looks kind of like a reverse switch, it closes when the shift fork in the rear axle physically moves to the locked position.

M1 and M2 output a constant voltage to move the motor until RLY1 and RLY2 match the desired position or it times out if they do not get there after a bit. It swaps polarity to move the motor the other direction.

Thanks, me and the others I mentioned there put alot of time and research into it and it's become a great help. Following the testing gets us to the problem pretty effectively most of the time.

 

Yes, put it up on stands, put it in 4 Lo, put the truck in neutral and shut it off. Turn back to where the dash is lit up but not running, activate the locker button and turn one rear wheel by hand. IF it's working, you'll hear it. Then you can push and release the button several times to exercise it a bit. I've had to do this on mine.