05 SR5 - ABS, VSC, Brake Lights stay on intermittently

[john123drury]

Hey gang - my 4Runner has about 172K on it. Runs like a champ. Over the past few weeks, I've had an intermittent issue with the dash lights on the right side coming on. (see attached photo) This happens when I first turn on and start the car.

BUT, it's rare. Most times it doesn't. They go off like they normally should after startup. Occasionally when it does happen, if I turn off the car, wait a few seconds, and then start it back up, the lights behave normally (they go off).

There are no other lights that stay on in the dash. These are the only ones. I haven't noticed anything different with the way the car handles. I have disconnected the battery overnight in an attempt to reset ECU, but that did not solve the problem.

Again...this is one of those things that is a nuisance because it only happens 25% of the time. So any suggestions would be appreciated. Thank you!

 

[lightfreak]

Most likely faulty brake light switch behind the brake pedal
Cheap part and DIY easy swap.
Also check your brake fluid.

 

[john123drury]

Thank you! Can you help me understand how the brake light switch would affect these lights? I thought it only controlled the lighting behind the vehicle. Not the dash lights...

Most likely faulty brake light switch behind the brake pedal
Cheap part and DIY easy swap.
Also check your brake fluid.

 

[lightfreak]

Thank you! Can you help me understand how the brake light switch would affect these lights? I thought it only controlled the lighting behind the vehicle. Not the dash lights...

It’s a safety feature , if the switch is faulty your rear brakes may not be lighting up. The lights on the dash are telling you something is wrong

 

[john123drury]

So after YEARS of attempting to figure out the issue, I believe I have isolated the problem. Let me say that I tried every single thing an internet search (and forum suggestions) yielded. So all the things like calibration, gas cap, brake booster, electrical lines, sensors, brake light switch, etc. - ALL of it was looked at or replaced and nothing helped.

About a month ago I swapped out my rear brakes and decided to remove the ABS sensors on the bearing assembly (simple one-bolt, pull out removal). They were caked in bearing grease. The REAR wheel bearings are no good. The grease that's been flinging from them internally covered up the rear sensors and caused the issue. I cleaned them, put them back, and the lights now function perfectly as they should. I have since replaced the driver side wheel bearing / axle, and have plans to do the passenger side next when finances allow.

For anyone who has struggled with this issue as long as I have, this may be your solution. Check your rear wheel sensors to ensure they are clean. Hope it helps someone out there in the future.

 

[4runner4camping]

I'm having the same issue but it's accompanied by an alarm squeal and the sound of metal (traction initiating?).

 

[hutchison]

I am going to tack my findings onto the end of this post, it was the most recent one i could find.

I had been throwing ABS VSC fault lights like the OP had.

skiddy car, VSC TRAC, VSC OFF, ABS

for 3-4 months, i decided i would swap out the ABS sensors (i had previously planned to remove the wheels and clean the brakes after the cold weather)
so it was not an extra big deal.

i swapped out the sensors , still had the fault light,
brought a code reader with ABS pulled some codes, it was throwing

C1223 abs control sys malfunction
C1249 open circuit in stop light switch
U0073 control module communication bus off
U0123 lost communication with yaw rate sensor
U0124 lost communication with lateral accel sensor mod
U0126 lost comms with steering angle sensor.

after some further hunting i came up with this brake light switch fault from a couple of forums, swapped it out, job done.
SLA1024 was the switch, that works for runners up to 7/31/2005. after that you need SLA1028.

when i look back at the symptoms, it would usually come on after i hit the brake , it makes sense, but it felt more random, as i rarely hit the brakes sometimes. i need to sharpen my trouble shooting skills. i killed some OEM toyota abs sensors in the process, saving grace was the replacements were cheap.

thanks to all the forum posters for continuing to log faults :bravo: