jim4runnerny
New member
See attached image from my receipt... looks like the detected an open circuit and replaced the harness. I didn't realize how much they actually took apart, wow.. Fortunately my truck has been rattle free ever since.
Jim
ABS, braking power low and drive start control malfunction lights
- Thread starter Ih8fizzix
- Start date
See attached image from my receipt... looks like the detected an open circuit and replaced the harness. I didn't realize how much they actually took apart, wow.. Fortunately my truck has been rattle free ever since.
Jim
i can't believe i fixed the ABS related issue on my 4runner. it seems like a software glitch on the system. when those error show up, the truck is drivabable except the abs system stopped working and the 4wheel drive system still works for 4h and 2h but not 4L.
while i was driving earlier, i tried pressing the brake with my left foot while i'm pressing the gas to accelerate and suddenly all the error disappeared. i tested the 4 wheel drive system, 4H, 2H, 4L, atrack, traction control and downhill assist started working again. i tested 1 wheel on ice while in 2H and the ABS worked also. if you have these errors, can you try these fix and let me know? there must be something that must have been done with the braking and gas pedal to activate those malfunction. now it's fixed. i wonder if toyota is aware of those issues.
while i was driving earlier, i tried pressing the brake with my left foot while i'm pressing the gas to accelerate and suddenly all the error disappeared. i tested the 4 wheel drive system, 4H, 2H, 4L, atrack, traction control and downhill assist started working again. i tested 1 wheel on ice while in 2H and the ABS worked also. if you have these errors, can you try these fix and let me know? there must be something that must have been done with the braking and gas pedal to activate those malfunction. now it's fixed. i wonder if toyota is aware of those issues.
Charles Bronson
Member
That's a hell of a find. I too was thinking it had to be some sort of electrical glitch given that this issue has popped up with such frequency in the last month or less and only appears to affect those that got the recent winter snowy blasts.
I have little hope that the part our tech ordered is the fix and I hope to God it doesn't lead to the work that jim4runnerny's 4runner needed.
At the start of the thread, Toyota replaced a brake booster and master cylinder. For one 4runner, the master cylinder was the fix. Then jim4runnerny says Toyota replaced a major wiring harness and that fixed it. On our 4runner, they replaced a wheel speed sensor and that didn't fix it. Then they ordered an electronic ABS/brake controller and we're waiting on that. 4r-4ever apparently fixes his 4runner by torque braking it from a roll :crazy:
I get the sense that Toyota has not a clue about what's happening here. I think the issue is related to a glitch with the Toyota Safety Sense P (TSS-P) system which became available on the 2020 models. That system is heavily integrated into the ABS system, much more so than the previous TSS system.
Last edited:
i know right! i was ready to schedule with toyota to get it looked at. now i'm wondering whether the fix that toyota did was actually the fix. those abs/brake booster probably is not the problem. i just played around with the brakes with my left foot and right foot with the gas pedal and it fixed it. i'm curious now if others who may have the same problem could fix it this way. i would say a software glitch somewhere.
Charles Bronson
Member
I forwarded this potential two pedal fix to my service advisor and he said he forwarded it to the tech. We'll see. Many techs don't like to be told their job, especially if some guy found something "on the internet". It's understandable. It still worth a shot though.
thank you for forwarding it to your advisor. they might be able to look into this
more and we might all get a software fix to this or whatever recall they need to do.
more and we might all get a software fix to this or whatever recall they need to do.
Charles Bronson
Member
No word from the service advisor regarding if the tech tried this out. Sounds like they're going to do it the hard way first
Ok. good to know. try pressing the gas at around 40miles an hour and hold it there and then press the brake with your left foot. That's was what I did.
Charles Bronson
Member
2/17 Update
We've been told the ABS module they ordered for our 2020 4Runner likely won't be here for another 1 to 4 weeks. That puts the truck potentially out of service for well over 30 consecutive days, potentially 40+ days. I have little faith that the ABS module will fix the issue either given the multitude of "fixes" listed in this thread. We may be pursuing a lemon law buyback if the module doesn't fix it and the truck has been out 30+ days. Automakers are required under law to keep a sufficient inventory of parts to fix vehicles 10 years or newer from the model year. "Sufficient" is 7 business days or less to get the part. I understand COVID may be creating supply issues, but the law is the law. Not in a million years would I think I'd be considering a lemon buyback on a Toyota, especially the most reliable Toyota in their line up! LOL
Also, they didn't try the brake pedal/gas technique I asked them to try and they won't let us come up and try it either.
Last edited:
Charles Bronson
Member
2/24/2022 Update
So the dealer let us come up and try the brake/accelerator test on our 4runner today. The truck had been sitting since 2/4. It started right up even though temps had been quite low. Today it was snowing and cold as well.
When I started the truck, the brake warning lights were on. I let the truck sit for over a minute. While in neutral, I pressed the gas and brake and the warning lights stayed on. I tried this three times. I then put the truck into gear and did the brake/accelerator test. Within 5 seconds, the warning lights cleared. The wife and I then drove around for 20 minutes and the lights stayed off. We then went to a snowy parking lot and tested the ABS and traction control. All systems functioned as designed. The ABS pulsated and the traction light flickered as the rear tries scrambled for traction. As I noted earlier in the thread, when the warning lights are on, there's no ABS or traction control; the 1980s all over again :happy:
We returned the truck to the dealer and told them the lights were off. The service advisor said the part would be here tomorrow. If it's not in tomorrow, we'll likely request to get our truck back and will bring it back in when the part shows. I totally respect the tech's job and the process, but we'd rather not be without our truck for any longer than necessary, especially if it's working fine.
So the dealer let us come up and try the brake/accelerator test on our 4runner today. The truck had been sitting since 2/4. It started right up even though temps had been quite low. Today it was snowing and cold as well.
When I started the truck, the brake warning lights were on. I let the truck sit for over a minute. While in neutral, I pressed the gas and brake and the warning lights stayed on. I tried this three times. I then put the truck into gear and did the brake/accelerator test. Within 5 seconds, the warning lights cleared. The wife and I then drove around for 20 minutes and the lights stayed off. We then went to a snowy parking lot and tested the ABS and traction control. All systems functioned as designed. The ABS pulsated and the traction light flickered as the rear tries scrambled for traction. As I noted earlier in the thread, when the warning lights are on, there's no ABS or traction control; the 1980s all over again :happy:
We returned the truck to the dealer and told them the lights were off. The service advisor said the part would be here tomorrow. If it's not in tomorrow, we'll likely request to get our truck back and will bring it back in when the part shows. I totally respect the tech's job and the process, but we'd rather not be without our truck for any longer than necessary, especially if it's working fine.
Last edited:
Charles Bronson
Member
2/28/2022 Update
The service advisor called us on the morning of Friday 2/25 and said the part likely won't be in until late March so we could come get the truck if we wanted it and to bring it back when the part is in. They want to replace the part because that was the tech's diagnosis and the tech/dealer won't get paid if the work isn't done. Ok fine, but we won't be in a rush to bring the truck back until it's convenient for us, not them. Not like the part will make a difference anyways. It's not a hard part issue.
The truck was given to us covered in snow, unwashed, and the drivers side foot panel cover and kickplate removed, exposing wiring looms and the computers to the left of the driver's dead pedal. I'll give the tech and service advisor the benefit of the doubt that the tech didn't know the truck was coming back to us and the service advisor didn't know the panels were removed and sitting in the back seat. Being a car guy, I put everything back together myself in a few minutes, but I doubt most people would have been able to put it back together without breaking tabs, clips, and such. The truck has been driving fine since we picked it up 4 days ago.
Whatever.
The service advisor called us on the morning of Friday 2/25 and said the part likely won't be in until late March so we could come get the truck if we wanted it and to bring it back when the part is in. They want to replace the part because that was the tech's diagnosis and the tech/dealer won't get paid if the work isn't done. Ok fine, but we won't be in a rush to bring the truck back until it's convenient for us, not them. Not like the part will make a difference anyways. It's not a hard part issue.
The truck was given to us covered in snow, unwashed, and the drivers side foot panel cover and kickplate removed, exposing wiring looms and the computers to the left of the driver's dead pedal. I'll give the tech and service advisor the benefit of the doubt that the tech didn't know the truck was coming back to us and the service advisor didn't know the panels were removed and sitting in the back seat. Being a car guy, I put everything back together myself in a few minutes, but I doubt most people would have been able to put it back together without breaking tabs, clips, and such. The truck has been driving fine since we picked it up 4 days ago.
Whatever.
Last edited:
Thank you for testing that. So far, on my truck, it did not come back. It came back February 16 for a few seconds and disappeared. So far, it did not come back on yet.
Charles Bronson
Member
3/24/2022 Update
Another update and hopefully the last. As previously noted, I remedied the ABS error issue by simply hitting the brake and gas at the same time. We had driven the truck for well over a thousand miles and nearly a month, including a road trip to northern Arkansas. The truck had no issues.
The part that was backordered finally showed up on 3/18 (right at 4 weeks since the order). The part in question is the electronic brake booster module which mounts to the fender side of the master cylinder (part no. 47217-35250).
On 3/22, we brought the truck in to replace the part, even though we knew it was HIGHLY unlikely it was the source of the issue. They said it would be fixed the same day. We got a call at 5pm on 3/22 that the tech was having problems getting the air out the brake lines and he would need to work on it in the morning.
On 3/23, my wife picked up the truck and immediately heard and felt (through the brake pedal) a light clunk/knock when using the brakes. She's not a car person, but even she knew this wasn't right. I told her to take it back immediately and tell them to figure out what's happening. The tech takes a look and says that he can feel/hear the knock but then proceeds to tell my wife this a normal sound in 4Runners and it is the result of the brake pump assembly working and there's nothing they can do about it.
I get home from work and take a look. The knocking sound definitely wasn't there before. I then reach down and grab the top of the pump assembly and wiggle it. "Knock knock knock". So I get my scope out and inspect. The audible clunk/knock is being caused by metal to metal contact of the pump assembly body mounting points contacting the hex bolt mounting pins to the master cylinder. There is rubber bushing between the pin and mounting point, but the tech somehow knocked the pump assembly out of alignment when messing with the brake lines to the point that the pump assembly had shifted slighting, thus the bushings were fully stretched and the pins were hitting the pump mounting points (see attached pictures). The first picture is the front mounting point and the second is the rear mounting point. Yes, Mr. Tech man, it is the pump assembly, but it was your work that caused the issue and it is not a normal sound. A little adjustment of the brake line and the sound disappeared. I diagnosed this issue in 5 freaking minutes and fixed it in 1 minute once I figured out what I needed to do.
This morning my wife let the service advisor know that I fixed the issue and he has asked for pictures. They're not touching the truck again.
I feel bad for people that don't have the mechanical ability to troubleshoot stuff like this. Most anyone else would have just lived with this because the tech was too lazy to troubleshoot his work. What's even funnier is that he pointed at the pump when talking to my wife. I then thought "Well, let's start there".
My first questions to anyone that's having a problem on their car are the following:
1) Have you screwed with the car recently?
2) If yes, does the sound/issue seem to be related to that area you worked in?
More often than not, issues like this are caused by user/operator error. I'm guilty of this a million times over.
Another update and hopefully the last. As previously noted, I remedied the ABS error issue by simply hitting the brake and gas at the same time. We had driven the truck for well over a thousand miles and nearly a month, including a road trip to northern Arkansas. The truck had no issues.
The part that was backordered finally showed up on 3/18 (right at 4 weeks since the order). The part in question is the electronic brake booster module which mounts to the fender side of the master cylinder (part no. 47217-35250).
On 3/22, we brought the truck in to replace the part, even though we knew it was HIGHLY unlikely it was the source of the issue. They said it would be fixed the same day. We got a call at 5pm on 3/22 that the tech was having problems getting the air out the brake lines and he would need to work on it in the morning.
On 3/23, my wife picked up the truck and immediately heard and felt (through the brake pedal) a light clunk/knock when using the brakes. She's not a car person, but even she knew this wasn't right. I told her to take it back immediately and tell them to figure out what's happening. The tech takes a look and says that he can feel/hear the knock but then proceeds to tell my wife this a normal sound in 4Runners and it is the result of the brake pump assembly working and there's nothing they can do about it.
I get home from work and take a look. The knocking sound definitely wasn't there before. I then reach down and grab the top of the pump assembly and wiggle it. "Knock knock knock". So I get my scope out and inspect. The audible clunk/knock is being caused by metal to metal contact of the pump assembly body mounting points contacting the hex bolt mounting pins to the master cylinder. There is rubber bushing between the pin and mounting point, but the tech somehow knocked the pump assembly out of alignment when messing with the brake lines to the point that the pump assembly had shifted slighting, thus the bushings were fully stretched and the pins were hitting the pump mounting points (see attached pictures). The first picture is the front mounting point and the second is the rear mounting point. Yes, Mr. Tech man, it is the pump assembly, but it was your work that caused the issue and it is not a normal sound. A little adjustment of the brake line and the sound disappeared. I diagnosed this issue in 5 freaking minutes and fixed it in 1 minute once I figured out what I needed to do.
This morning my wife let the service advisor know that I fixed the issue and he has asked for pictures. They're not touching the truck again.
I feel bad for people that don't have the mechanical ability to troubleshoot stuff like this. Most anyone else would have just lived with this because the tech was too lazy to troubleshoot his work. What's even funnier is that he pointed at the pump when talking to my wife. I then thought "Well, let's start there".
My first questions to anyone that's having a problem on their car are the following:
1) Have you screwed with the car recently?
2) If yes, does the sound/issue seem to be related to that area you worked in?
More often than not, issues like this are caused by user/operator error. I'm guilty of this a million times over.
Attachments
Last edited:
Same code popped up on my 4runner 2021 ORP took it in on 22 Mar 2022 got it back same day. Dealer told me that the sensor was dirty and cleaned it off and I went on my way. Today on my way home from it came back on while I was a stop light. Called the rep I was dealing with and she was so surprised. I was able to make an appt 0700 tomorrow morning. lets see what they say. another thing last week out of nowhere I had the brake message pop up. could that have been a sign? I was reading the forum and I did not notice if that happened to anyone. just FYI. Im going to tell the rep all the info I have read today on this forum thank you all!
I have something similar, but no warning lights have come on yet. About every 8-10 seconds my brake pump activates like it is losing pressure in the brake system. The tech said my whole ABS system needs replaced, which is about a 4k job, but I've been driving it this way now for about 6 months and I haven't had any other issues other than the brief pressure pump activating.....weird!
Charles Bronson
Member
Toyota doesn't have a clue about what's happening or the cause of this issue. Why do I say that? Look at all the expensive fixes tech's have made to remedy the same issue. As an engineer, this makes absolutely no sense to me. I feel REALLY bad for anyone that deals with this issue outside of warranty as you could be looking at multi-thousand dollar repairs as techs just throw parts at it to see what may stick all at your expense.
My experience with fixing the issue by pressing the accelerator and brake pedal together has not been seen my Toyota because the work invoice says that the electronic brake booster module fixed the issue which isn't true as the issue was fixed a MONTH because that part went it. The dealer stuck Toyota with a $2300 bill to replace a wheel speed sensor (the first attempt to fix the issue) and then the electronic brake booster module and a full brake fluid flush.
Long story short, our dealer wanted to install this part or else they'd have no way to charge Toyota for the warranty work or the part they ordered.
With no real path or idea of how to fix this issue and the lack of our dealer/tech letting Toyota know that hitting the accelerator and brake pedals at the same time may remedy the issue, there's no real hope right now for Toyota engineers to look into this and issue a TSB or safety recall.
I think this is a quite a serious safety issue when this problem occurs because you lose traction control, stability control, and ABS. The 4Runner depends on these systems to work because the brake bias is actually strong to the rear which is rather odd, IMO. When this issue happened and I tried emergency braking, the rear axle actually wanted to swing around which is very spooky and without the track driving skills I have, it could have been quite dangerous. Most folks wouldn't know what to do in a situation like that. My first few cars had no nannies, ABS, etc. None of them would swing the rear around under threshold braking.
Drive very defensively if this issue happens in your 4Runner.
Last edited:
Charles Bronson
Member
What's the sound like you're hearing? It's my understanding from the Toyota tech that the pump cycles quite a often during normal operation off-brake operations and when you apply the brakes, the assembly shifts around quite a bit as the brake fluid/pressure go through the pump. The pump itself is suspended on three bushings. If the pump isn't perfectly centered in those bushings, there can be metal to metal contact which then transfers sound to the firewall and a sensation (in our case) through the brake pedal.
You might want to open the hood and grab the top of the pump housing (looks like a silver soda can to the left of the brake fluid reservoir) and try and lightly/loosely wiggle it around with your hand. If you feel and hear metal to metal contact with barely any wiggling, that could be the source of what you're hearing.
Have you had any brake work or done any work under the hood in that area recently?
Last edited:
so just got off the phone with the dealer and still no resolution with the issue... they told me that the lead technician only works M-F but is willing to take my vehicle home for the weekend and drive it around. thought that's kind of odd. anyone had that ask of them?
told them that I was not comfortable technician taking it home and would rather not. if he is off on the weekend what would be the difference if they wait on Monday? they couldn't give me a loaner because I did not allow the technician to take it home and drive my truck around thru out the weekend. I asked if I could take it home and drive it around myself said it was not advisable. what's anyone's thoughts? dealer contacted Toyota and said it was above them. I ask if they have heard if other vehicles had the same issue with the same thing rep wasn't able to say. I get it she was just doing her job. but if this has occurred to others they need to notify people about the issue and figure it out.
told them that I was not comfortable technician taking it home and would rather not. if he is off on the weekend what would be the difference if they wait on Monday? they couldn't give me a loaner because I did not allow the technician to take it home and drive my truck around thru out the weekend. I asked if I could take it home and drive it around myself said it was not advisable. what's anyone's thoughts? dealer contacted Toyota and said it was above them. I ask if they have heard if other vehicles had the same issue with the same thing rep wasn't able to say. I get it she was just doing her job. but if this has occurred to others they need to notify people about the issue and figure it out.
Last edited:
Charles Bronson
Member
Yeah, good call on not letting a tech take your 4Runner home for the weekend. What a weird offer on their end.
Keep us posted to their "solution". Maybe have them try the brake/gas pedal fix? Keep in mind most techs/service advisors don't take kindly to people saying that they researched something on the internet. I get it, they don't want to be told their job, but any good engineer/tech should be open to all ideas.
