Make sure that is not just what they are telling you!!!
It is a known issue from what I hear..
ABS, braking power low and drive start control malfunction lights
- Thread starter Ih8fizzix
- Start date
It is a known issue from what I hear..
UPDATE: The FIX: It appears as though the root of the issue is a "rear-wheel speed monitoring problem." The Toyota Tech and Engineer did a "live data" road-test and discovered that one of my rear wheel speed sensors was cutting in and out randomly. After another quick inspection it was determined that the sensor itself was fine.
(...no surprise, as that was recently replaced a few months earlier.) A continuity test confirmed it.
Working backwards from there, they identified the problem was, in fact the "rear wheel ABS harness assembly." Turns out the boot that connects to the wheel sensor itself was quite corroded, from obviously getting wet/snow/etc. Now this shouldn't actually happen if the boot sealed appropriately where it connects to the sensor, but this isn't happening. Once corrosion gets in it can really mess up the continuity of the harness. (Again, continuity tests confirmed the actual harness was the problem.)
Toyota replaced the harness and we're all good now. They added a lot of extra dielectric grease to ensure that things sealed up better when connecting to the main harness and the wheel speed sensor.
This is clearly a faulty design of the rear ABS harness. If a good seal cannot be attained, it will always be susceptible to corrosion ..... thus, if they continue to use the same part without re-designing a better solution, it will likely continue to happen again and again, over time.
This is on Toyota, so if it happens again, even if I'm off warranty, they will be responsible. Gotta love electronics. All this from a little corrosion.
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The problem ...and the "fix" I've posting about happened on my 2022 model year. So it's definitely common problem, from 2020 through 2022.
(Sorry, I can't say if it's affecting 2023 models or not, though.)
It look like there is more than one cause for this, but some of them are from damaged or corroded wheel speed sensors. Would these help or just trap more gunk and make them corrode even faster?
Jomax Customs
Jomax Customs
MAD 69
New member
I got all these codes today plus the check engine - 5 different codes on my '23 with 6k miles. I've never even put it into 4WD yet, haven't gotten first oil change yet. My '98 4R SR5 has almost 300k miles and has been to hell and back has never thrown a code in the 24 years I've had it.
Paid almost 60k for this new one and dealer says they need to replace the accelerator pedal assembly, not sure if it's under warranty - the Stealership will let me know, I didn't buy any extended warranty - didn't think it would crap out this soon, ridiculous
Paid almost 60k for this new one and dealer says they need to replace the accelerator pedal assembly, not sure if it's under warranty - the Stealership will let me know, I didn't buy any extended warranty - didn't think it would crap out this soon, ridiculous
wackerman1
New member
2020 Limited 4Runner AWD same issues
My son came home from college and he told me there are 5 malfunction messages.
Anti-Lock Brake malfunction
Drive Start Control malfunction
Braking Power Low
Pre-Collision System Malfunction
Cruise Control Malfunction
I went to my local garage and they hooked up a Snap-On scanner and it said right rear wheel speed sensor not working. They replaced it and a day later the lights came back on. I read all the issues in this thread and the one by YotaTurd caught my attention. I told my mechanic about this thread and we decided to hook up scanner and go for a ride. BTW these warnings were intermittent. The warnings were not on for the first part of the ride and scanner detected no problems. The tech said let's stop and I am going to get out and jiggle the wire assembly. The second he jiggled the harness all the warnings came on. Put the 4Runner on the lift and he found the one wire in the assembly was badly corroded. Replaced the wire and the problem was gone. That was a month ago now and all is good. Without this forum I'm not sure how this would have turned out. Thanks to everyone who posted
My son came home from college and he told me there are 5 malfunction messages.
Anti-Lock Brake malfunction
Drive Start Control malfunction
Braking Power Low
Pre-Collision System Malfunction
Cruise Control Malfunction
I went to my local garage and they hooked up a Snap-On scanner and it said right rear wheel speed sensor not working. They replaced it and a day later the lights came back on. I read all the issues in this thread and the one by YotaTurd caught my attention. I told my mechanic about this thread and we decided to hook up scanner and go for a ride. BTW these warnings were intermittent. The warnings were not on for the first part of the ride and scanner detected no problems. The tech said let's stop and I am going to get out and jiggle the wire assembly. The second he jiggled the harness all the warnings came on. Put the 4Runner on the lift and he found the one wire in the assembly was badly corroded. Replaced the wire and the problem was gone. That was a month ago now and all is good. Without this forum I'm not sure how this would have turned out. Thanks to everyone who posted
Glad it helped, wackerman1. This forum and the folks on it have been a great help to me ...and are a tremendous value for us all.
tbm837
Member
The poor tech at the shop probably got paid for just the install of the bad part, not the time it took to remove and replace all the other components to get to the bad part.
i now have this issue. 2020, 55k miles. cold weather in nj after a road to trip to the mountains and a good amount of 4wd usage in the snow.
my errors are:
ABS malfunction
pre-collision system
drive start control
2wd-4wd mode change malfunction
christmas tree lit up around 70mph on the highway in 2wd. after about 15 minutes of driving it all went away.
a lot of people in this thread seem to have experienced this issue but the one key takeaway i've seen is corroded abs harness.
can anyone else say what they've seen the issue be solved with?
the car was just dropped off at the dealer and i'd like to be prepared when they call back with something that almost certainly isn't the problem.
my errors are:
ABS malfunction
pre-collision system
drive start control
2wd-4wd mode change malfunction
christmas tree lit up around 70mph on the highway in 2wd. after about 15 minutes of driving it all went away.
a lot of people in this thread seem to have experienced this issue but the one key takeaway i've seen is corroded abs harness.
can anyone else say what they've seen the issue be solved with?
the car was just dropped off at the dealer and i'd like to be prepared when they call back with something that almost certainly isn't the problem.
well, for anyone that sees this, toyota had a look at the car. code P2443 came up and they're recommending: "REPLACE BANK 2 SECONDARY AIR INJECTION, GASKETS, AND HARDWARE" at a cost of $2k.
after some research, and a lot of time with GPT, it sounds like the issue is more likely some electric fault (short term drop in voltage) and this code was thrown downstream. the secondary air injection pump only runs at cold start for 20-90 seconds to have that throw every other error under the sun 10 minutes after cold start would be unlikely. there are no other symptoms that would suggest the air pump is faulty.
funny enough, the battery test also failed (the SA failed to mention that but I did see his screenshot).
i'm going to change the battery and see if it happens again
after some research, and a lot of time with GPT, it sounds like the issue is more likely some electric fault (short term drop in voltage) and this code was thrown downstream. the secondary air injection pump only runs at cold start for 20-90 seconds to have that throw every other error under the sun 10 minutes after cold start would be unlikely. there are no other symptoms that would suggest the air pump is faulty.
funny enough, the battery test also failed (the SA failed to mention that but I did see his screenshot).
i'm going to change the battery and see if it happens again
