This just happened now. On my 2020 SR5 4x4 with 11k miles.

Display says anti lock system malfunction visit dealer. braking power low,drive start control failure visit dealer.

Will take it in Monday when the dealers open. Has this happened to anyone before? I drove the car this afternoon and moved it from the drievsy to the street. Wife got in to drive it, and called me saying all these warnings are lit up. So random. She’s driving it now and says it’s driving fine, not sure if it’s because it’s brutally cold here so sensors are just acting up. It’s been between 0 and like 10 degrees all day and the car sits out.

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Tried to switch it from 4wd to 2wd and back to see if it was anything related to that and now it says 4wd malfunction!

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Update:

Dealer called and said a 2021 4Runner came in on Saturday with the same issue and that they’ve already done a wheel bearing and master cylinder on it and still not fixed.

He said on mine they’re going to start with a brake booster and that it won’t be here until earliest Friday. He said on the 2021 the brake booster is backordered and won’t be here until the 25th.

In the meantime I’m driving around a 2020 Rav4.

Just in case anyone cares, it was a failed master brake cylinder. They replaced it under warranty. They also found a bent brake line. I had to pay out of pocket for that.

Yikes, that's an expensive part. I had to replace one on my 2001 3rd gen 4Runner and the part was over $2k. I haven't seen many failures pop up on 4th and 5th gens which use a similar design boost pump/accumulator setup, but hopefully it's less common than the old 4Runners and Landcruisers which had lots of issues with them as they aged.

Looks like they replaced the whole booster instead of the pressure sensor

Guaranteed it was the sensor or bad connection no way a master cylinder is dead after 11k

Reminds me of the master cylinder fiasco at gm dealers in the 80's and 90's pedal going to floor and they say replace master cylinder .... Then again in 6 months pedal going to floor replace master cylinder

*** All they had to do was adjust the automatic brake adjusters in the rear that never adjusted properly**

How many people got ripped off with that

Thats why I love this site!!
My Wife's 2021 woth 26k just went in the shop on Friday for the exact same thing..
I was going to post because the dealership we are forced to goto is HORRIBLE.
Already they said it was going to be 2 weeks to get part from California. I told them its only a 4 day UPS or a 1 day transit via UPS NDA .
They said thats what they were told to tell us .
Also They tried to force her to rent a car from them.. So I called Toyota and got their opinion ... We picked up the loaner on Saturday..
Then the stealership called with a quote to trade it in with a brand new 2024 just out of the blue..

I don't have this issue with my 2018 TRD Off-Road.
Never had it with the 2014, the 2010, or the 2006 4runners either.
It seems to have started with the 2021 Toyota models.

Old post, but I just had this exact issue occur on my 2020 4WD 4Runner Limited with 15000 miles. I have an appointment on Monday to have this looked at. Note that it happened to me after the vehicle sat for a day in cold weather (~10-20 degF). I'll let you all know if it ends up being a master cylinder for me as well.

Jim

just had this happen on my 2021 limited too minutes ago, did you ever figure out what it was? same deal as everyone else, sat out in the cold and then started it and got these messages

This is hilarious. I just dropped my wife's 2020 TRD ORP with 20K miles at the dealer for these exact messages. She got the messages after driving around for an hour in ~15 degree weather. The truck sits in a garage all night, but the garage was probably 35 degrees last night. Not exactly super cold.

jim4runnerny or moes4runner,

Do you have any updates to what Toyota did to fix this issue? The tech thought it was a wheel sensor so he replaced it and the issue is still there.

The tech says the electronic ABS/brake controller is bad and has ordered one. I'll update this thread once the repair is done and note if it fixed the issue.

Hi all,

They ended up replacing a major wire harness in my vehicle to resolve the issue. Whatever it was, they had to pull the back seats out to do it, as I drove around without the seats secured while I waited for the part to come in. I'll check my receipt to see if a part number was called out.

I suspect the wire-harness was common between all the sensors acting up, so they decided to replace it. I asked if there was rodent damage (chewing), and they said no, and alluded to all the high speed data travelling in the harness and it is not something that can be repaired, only replaced.

It has been really cold out and I have not seen the issue since the repair, so fingers crossed it is fixed. Good luck!

Jim