[emt3]

All 4 warning lights came on yesterday when started car 2007 Prius with 125K miles. Brakes working but grabbing with added pedal pressure. Need help on how to diagnose.

 

[fdret44]

Did the lights turn off, and did the problem happen again the next time you turned on you car? Might be a 12v battery problem. In any case, you should get it checked out as that is a safety issue with the brakes.

 

[firepa63]

Get the codes and post them here to help diagnose the problem. If those warning lights stay on DO NOT DRIVE THE CAR!

 

[Phoenix]

Lots of unusual problems can pop up when the 12-volt battery goes bad and the voltage drops to 10.5-11 volts or lower. Before spending time and money troubleshooting these problems, if you still have the original 12-volt battery, you might want to check it to verify that the battery is OK. If the voltage is low, most auto parts stores will charge and load test it for free (because they want to sell you a new battery).

I have purchased a couple of batteries from eLearnAid:

http://www.elearnaid.com/priusparts.html

Bernie Littman is very helpful, and his prices are competitive for hard to find Optima batteries.

Otherwise, most auto parts stores will also read the fail codes for free; and those codes will help others on this site to provide more accurate troubleshooting advice.

Good luck!

 

[TucsonCamper]

1) R&R 12V battery
2) Check if there is any damaged harnesses.
We have pack rats (yes rats) in Tucson that love to chew on cable insulation. I had an Honda Element that had to be towed and a $300 repair due to this.

If not fixed then get the dealer to test the hybrid battery.

 

[cptjames]

Brake, (!), ABS, VSC Lights Warning Lights Popped On

Almost home when 4 warning lights (Brake, (!), ABS, VSC) came on Friday after driving about 45 minutes from work (around 13-15 miles). 2006 Prius with 133K miles. Brakes working. Found this forum and took car to garage next day. 12 volt battery replaced (garage owner said it was a Toyota brand, could have been the original). No problems driving until today, same symptoms, lights came on again while driving home from work, this time farther from home. If it's not the 12v battery, what else could it be? Will be taking it back to the garage first thing in the morning.

 

[Mike Colburn]

This could be your Brake Actuator going out. Take it into the deal IMMEDIATELY. My brakes were making a BARKING noise, and I could hear a motor or something cycling on and off every 5 seconds or so. Then all those lights went on!

Turns out that in my 06 that part is under warranty until Dec 31, 2017!! Yeah you read that right, NEXT December. It's a known bad part.

When they look it up, have them look up the ORIGINAL warranty, not the secondary warranty. It's a $2300 repair, you don't want to have to fork that over if you don't need to.

If your actuator goes out, you will lose your brakes (it could happen while you're driving).

 

[bmt]

Thanks

This could be your Brake Actuator going out. Take it into the deal IMMEDIATELY. My brakes were making a BARKING noise, and I could hear a motor or something cycling on and off every 5 seconds or so. Then all those lights went on!

Turns out that in my 06 that part is under warranty until Dec 31, 2017!! Yeah you read that right, NEXT December. It's a known bad part.

When they look it up, have them look up the ORIGINAL warranty, not the secondary warranty. It's a $2300 repair, you don't want to have to fork that over if you don't need to.

If your actuator goes out, you will lose your brakes (it could happen while you're driving).

I just want to say thanks to the forum for info about the actuary. Three weeks after paying cash for a 12 year old Prius (2005) my entire dash lit up like a Christmas tree. I was able to tell the dealership that I was under an extended warranty for the break actuary. They made the repair and gave me a rental for 1 week all at no charge. Unfortunately, I'm back to the forums because all my lights have gone off again. I'm hoping it is a bad replacement part...time will tell!

 

[SweKiwi]

How did it go? Also have the problem with the three yellow symbols, but only when going faster than 113 km/h.
A few months ago it was when going faster than 128 km/h.

 

[Menghuot]

Hello cptjames,

I faced the same issue like yours. I have my Prius 2006 Half Full, checked by specialized garage . They detected with their computer analysis on the car, it shows as per screen.

Next day, I started the engine again, it alerts "Brake, (!), ABS, VSC Lights Warning Lights Popped On" again. I went to another garage, and have its original battery Voltage replaced. I ride for one day, the alerts "Brake, (!), ABS, VSC Lights Warning Lights Popped On" disappeared.

Today, it alerts "Brake, (!), ABS, VSC Lights Warning Lights Popped On" again with new battery.

Any suggestion, Prius fan.!!! Please.!!!

Brake, (!), ABS, VSC Lights Warning Lights Popped On

Almost home when 4 warning lights (Brake, (!), ABS, VSC) came on Friday after driving about 45 minutes from work (around 13-15 miles). 2006 Prius with 133K miles. Brakes working. Found this forum and took car to garage next day. 12 volt battery replaced (garage owner said it was a Toyota brand, could have been the original). No problems driving until today, same symptoms, lights came on again while driving home from work, this time farther from home. If it's not the 12v battery, what else could it be? Will be taking it back to the garage first thing in the morning.

 

[Tomzabob]

All 4 warning lights came on yesterday when started car 2007 Prius with 125K miles. Brakes working but grabbing with added pedal pressure. Need help on how to diagnose.

Its the brake actuator. Very expensive part. Find used part. Mechanic told me safe to drive until it starts beeping

 

[Iam Ghost]

All 4 warning lights came on yesterday when started car 2007 Prius with 125K miles. Brakes working but grabbing with added pedal pressure. Need help on how to diagnose.

I apologize for arriving so late to the party but hopefully this will help future people like me. I had the same issue, just replaced the 12 volt battery didn't fix that issue, looked into trying to clean sensors, freekin out thinking it might be the brake actuator ($4500.00 part). Read a thread somewhere about gas cap, thought that's the stupidest thing I've ever heard, but tried it anyway, PROBLEM SOLVED!!! how the gas cap being defective messes with the breaks and traction control I have no clue but that stopped the arey of random break warning lights. Strangly yet still my check engine light never came on just break and traction lights, (I say strangly because your check engine light is emissions).

 

[patrick_g]

All 4 warning lights came on yesterday when started car 2007 Prius with 125K miles. Brakes working but grabbing with added pedal pressure. Need help on how to diagnose.

I had the same indications and it was the traction battery. Replaced it under warranty and all is good.

 

[Lumius]

I apologize for arriving so late to the party but hopefully this will help future people like me. I had the same issue, just replaced the 12 volt battery didn't fix that issue, looked into trying to clean sensors, freekin out thinking it might be the brake actuator ($4500.00 part). Read a thread somewhere about gas cap, thought that's the stupidest thing I've ever heard, but tried it anyway, PROBLEM SOLVED!!! how the gas cap being defective messes with the breaks and traction control I have no clue but that stopped the arey of random break warning lights. Strangly yet still my check engine light never came on just break and traction lights, (I say strangly because your check engine light is emissions).

WHAT THIS GUY SAID!! Traction, PCS, ABS & BRAKE lights all came in on the expressway far from home. If I didn’t read through the replies I would never had tried to unscrew the gas cap and restart the car.

 

[Iam Ghost]

WHAT THIS GUY SAID!! Traction, PCS, ABS & BRAKE lights all came in on the expressway far from home. If I didn’t read through the replies I would never had tried to unscrew the gas cap and restart the car.

I'm so very glad this helped, when I found this thread it was years old but it got me in the right direction, so I figured it might help someone else.
If your abs Vsc traction lights come back on I recently discovered how to test without the $600 smart scan tool (fyi this only works for break systems not check engine light).

So you will want to use a paperclip and put it in the #4 & #13 spots on the obd plug (see diagram picture)

The normal start up of warning lights will do there thing after that happens your Vsc / abs / traction lights (depending on the issue) will start flashing rapidly count how many flashes, if there's a longer delay in the flashing lights it indicates the next number (EX: ABS flash.flash.flash 3 ... Flash.flash 2 would be code 32) If you missed it they will start over again after a slightly longer pause (I used my camera to video it). Each light (abs Vsc ect) is read independently so if you abs flashes and your Vsc also flashes there's two Separate codes. If it just flashes but does not pause it's indicating it's fine. After you have the codes you can find the answeres here:

The code you will aquire will link to the /# after the smart code numbers (C1253/53) would be 53 for example. This will at least get you a lot closer to the issue limiting time spent looking for it. This is right out of the technical manual the shop uses. I am also attaching the full manual pdf for reference.