VSC, ABS, (!) and emergency brake light on

Hi Patrick and everyone else, I had notices on a different threat that I can't find anymore that you told someone to post the flashing codes for advice. My prius is braking extremely hard at low and high speed even when I barely press the brake pedal. The flashing codes I got when doing the paper clip trick at the plug that's at them bottom of the driver side steering wheel where the following..


((!)) this one gives the code 2&6
ABS gives flash code 2-4
VSC code 5-4

Any Idea where I can find out what they mean? Any help is appreciated

 

jumper pins 4 to 13 on diagnostic plug and do the pump brake 8x for reset and shut off and remove jumper. worked for me

 

It was the brake actuator, replaced and it works great now. Thanks anyways

 

My 2004 Prius just started this same problem this past Saturday. Three or four weeks ago I went in for an oil change and had my brake rotors replaced because they were rusted, and the battery should only be about 2 years old (was replaced shortly before my parents bought the car in October 2013, I've been driving it since March of 2014). Car has 225k miles on it.

I'm not sure if the subtle differences I'm noticing while driving are actually happening or just in my head because of the lights being on. The breaks seem to be slightly more binary - less responsive with light pressure, more responsive to harder pressure. The gas engine seems to be running at times when it normally wouldn't (i.e. stopped at a light with the battery at least half charged) and running louder & less efficiently on the highway (used to average 48-52 mpg on the highway, now getting 43-45).

I drove the car to work and back on Thursday with no issue. Nobody drove it on Friday. Saturday night, a family friend drove it to pick up my sister and drove it to work Sunday morning. I noticed the lights Sunday night. He said the lights had been on since Saturday when he turned the car on the first time.

The only other issue I've ever had was about 18 months ago, the heat quit working and a week or so later the hybrid system began overheating. Had a water hose replaced and haven't had either problem since.

Edit: I don't have a multimeter on-hand to test the battery but I might as well pick one up. Will check the fault codes after work today and update

 

Used the maintenance mode display to check battery voltage, seems fine. 12.5 with no load, 12.0 with a load and 14.1 when the car is on.

 

Ok I'm definitely getting worse mileage and my battery is draining faster. I'd prefer not to go back to my dealer if it can be avoided. Any suggestions?

 

That's the most useful thing you can do at this point so that we can be able to help you. The best thing would be to get the full fault codes with a Mini VCI but, failing that, at least use a jumper wire and get the two digit blink codes. It will help a lot if you can post those.

The next thing that can be helpful is to remember that we don't all have the same model year you have so our service manuals won't all match, so once you have your codes, if you have time to look them up in the proper service manual for your year on techinfo.toyota.com and include a brief summary of what you found, that could save us making mistakes in case some details are different in ours.

Some people try to google their codes or look them up in other sources than the service manual and that can be a bit of a time waste, as sometimes the explanations that get dredged up are a bit bogus, either because they came from info on a different car, or they're just plain wrong. Often a scan tool itself will have a little one-liner explanation to show next to each code, but that's usually about as helpful as a fortune cookie.

-Chap

 

Here is my story and I hope someone can please help.

I have a Gen 2 2005 Prius in the United Kingdom.

I bought the car in March and a couple of months later I drove over 70 mph for the first time. The VCS, ABS and brake warning lights all turned yellow and stayed on.

I found out how to clear the lights using a metal paper clip as a jumper.

The lights stayed off for a few weeks until I next travelled on the motorway and they came on again at about 70 mph.

I decided to test the battery and got these readings.

12.1 without load
11.8 with load

Then I found out how to get the codes using the jumper and counting the flashes.

VSC 43 - capacitor malfunction
ABS 35 - foreign object is attached on tip of front right speed sensor
Brake 36 - foreign object is attached on tip of front left speed sensor

I found the explanation for the codes from an online repair manual and I think I have understood it correctly, although not sure about the VSC.

I don't know what to do next. I've cleared the codes again.

Could the codes be caused by the 12v battery being slightly low.
Do I need to repair / replace the speed sensors and wiring?

It seems strange to me that both speed sensors would fail at the same time and the codes only come on above 70 mph.

There is no noticeable difference to the breaks but maybe this is because you do not use the abs or the VSC unless you have to break suddenly.

Any help would be greatly appreciated.

Thanks, James

 

start with the battery. you can try charging it, and replace if it won't hold. it should be 12.4 or better, stone cold.

check out britprius, i think he got a good deal on exide over there.

if you're still getting codes after that, you'll probably have to buy the mini vci for code troubleshooting tree and toyota on line repair manual.

how many miles on her, how long have you owned, and do you know the history of service and accidents?

all the best!

 

I've only owned the car for 5 months and she has a full Toyota service history and coming up to 98,000 miles on the clock. No accidents as far as I can tell.

 

When you say "an online repair manual" do you mean the Toyota online repair manual at techinfo.toyota.com (or whatever is the site for the UK), which is always worth looking at, or some other thing you stumbled onto online, which will often be a waste of your time?

If you look up the codes you found in the Toyota manual, you will find anywhere from one to several pages for each one giving your next diagnostic steps to find out why you're getting that code and what to do about it. The suggestion from bisco about the Mini VCI scan tool may be useful, because sometimes the full five-character trouble codes are more specific than the two digit blink codes (as you'll see in the manual, sometimes the same blink code gets used for more than one DTC). But even starting with just the blink codes and the diagnostic steps in the manual, you'll be likely to get somewhere.

-Chap

 

The manual has all the codes and diagnostic steps. I'll post the link as soon as the forum permits me. Two of the codes, 35 and 36 seem pretty obvious speed sensor faults,but the 43 for VCS, is repeated with various full five-character trouble codes.

Maybe I'll just take off the front wheels and inspect the speed sensors.

James

 

Hello

If you have this problem remove the front wheels, remove and clean the speed sensors, then put it back together. Since doing this no warning lights have come on and the abs isn't playing up. I previously had clunking brakes at low speeds just before stopping and this has also stopped. Thank you to Prius Chat for saving me a trip to the dealer.

 

Could someone possibly lead me to a thread which explains this "paper clip method" to turn the brake warning lights off. Thanks very much...

 

I'm pretty sure you put the paper clip at the same terminals where you put it to read out the blink codes, and then if you want to clear them, a certain number of steps on the brake pedal will do that. I would search first for the threads on reading the brake blink codes. Then you'll know how to clear them too, but clearing them before reading them is kind of self-defeating. Strangely, clearing codes doesn't fix the actual problem ... only means maybe you forget about it for a while, however long before it's detected again and the lights come back, and you've missed that much time for possible diagnosis and repair on the way to it becoming a more persistent problem, or hard downtime.

-Chap

 

Thanks Chapman. I posted on Na3eem's thread about 12v battery problem, that I had all my brake light warnings coming on. I changed back to original tires and that didn't make a difference. So I bought a new 12v battery to no avail, although I am getting better fuel mileage now. As of right now, besides all the warning lights, there is hybrid battery drainage happening when I'm at a complete standstill with brakes fully pressed, and I'm hearing light knocking sounds from around the wheel well areas. Very much like what James909 is describing. I'm going to see if I can find some threads about locating and cleaning the speed sensors. Then try to reset the lights....

 

Okay, so I got the blink codes. Couldn't clear them after I read them. They are: ABS 4-2
(!) 6-4
VSC 4-5

The emergency brake light is also on but not blinking. As mentioned earlier, battery is discharging when at a complete stop with brakes fully pressed down, hybrid battery is having a little difficulty charging up, and I'm hearing some slight knocking sounds around the undercarriage probably around the wheel wells.

To read these codes I'm assuming I'm going to have to subscribe to the Toyota tech website?

Thanks for the help...

 

By the way for anyone else trying to read these codes there is a great picture posted by Seilerts here (post#3) regarding the slots to be used on the obd2 for this procedure....

VSC light is staying on | PriusChat

I used a thin piece of wire which was pushed into the two proper slots on the obd2, then pushed the power button on with the brakes pushed down to get into ready mode. It's not that difficult, but you do have to be a bit acrobatic to get under the dash and work on the obd2...

 

Well, it appears when I pumped the breaks eight times in sequence in an attempt to reset the brake warning lights a few times there appeared to be wet marks on the rear passenger rim. On further investigation there is brake fluid all along the ridge of the rotor. Checked the reservoir and it's below minimum. Brakes are extremely weak. Topped up with fluid and the brakes are effective again. It just gets weirder. I had the back brake shoes and a spring replaced and fixed up at a backyard mechanic last spring.

On the brighter side, after changing the 12v battery I'm getting fantastic fuel mileage. Just got 57 mpg on 90 kilometer run. The new battery is only measuring 12.7 no load, and 11.9-12v under load without lights on. Doesn't seem that impressive for a new battery. I asked them if they were charged batteries before having them put on in and the service rep just said, 'yeah, there all charged'.

 

The 64 from the ((!)) means you have a hydraulic failure in the right rear wheel, which is confirmed by your post below.

I hope you will stop driving the car, until you get the brake fluid leak repaired. If you can DIY, remove the tire and figure out where the leak is coming from - is the wheel cylinder bleeder valve just loose or is there a problem with the hose feeding the wheel cylinder?