Brakes Locking Up (Solved)

Today May 21, 2019. 3 times to Toyota dealer to find why rear passenger brakes lock up. They clean, lube and re-adjust the brakes.
4th time I had the E- brakes cable replaced $398.00 ( dealer gave me a break) no pun intended.

Today ( raining hard for two days) coffee farm, road were wet , slippery, 4H , driving slowly making a right turn, could feel tires slip, bam! Rear passenger brakes lock up. Reverse to free.
Drove a few more feet, bam! Passenger rear brakes locks up, reverse, happen one more time.

Mechanic tells me computer are not connected to brakes? Anti slip button i think is connected? I push they anti slip controls off, but it happen again, passenger brakes lock up as the tire spins.

Some one mention due to the lift? Only 2.5 inch lift. Replace the rear brake cable to longer cables.

Help! I will visit the Toyota dealer again.
Aloha

 

First off, I have a 4" lift and still have the stock E-brake cable and brake lines. Only need longer ones for 6" and up.
Second off, to me it sounds like it's the traction control ECU because that's the only computer that controls applying Brake pressure completely separate from your foot.

Get some dielectric degreaser, jack up the rear passenger, find where all the electrical hook-ups connect to the drum, degreaser all the connections (should be only 1 or 2), and place back in securely. If you want to take it a step further since you're down there, try to follow the lines underneath and degrease any hookup you can find.

The actual mechanical parts are fine since it only happens on rainy days. My issue was it would rain/snow then freeze the e-brake cable overnight because there was a kink in it. Your issue sounds like a short in the traction control.

If this doesn't work, start at where you think the problem is. Disconnect the transfer case actuator (this will throw up a dash light and shut off traction control) and drive around for a few days. See if it ever does it again. Otherwise, you can check the fuses for the 4wd ecu / abs (abs pump controls traction control). I think the interior one is
And the exterior one is

 

Thank you I will share this with the Toyota dealer.
Great suggestions!
Aloha

 

2020 TACOMA TRD PRO Rear brake were locking up for no reason..EASY fix ...spring of parking brake cable was stock and just by touching( put 1 or 2 finger were arrow shows CLICK back to its place.