How do you reset ABS light & yellow ((!)) ?

I had to do this some years ago on my 2007 when I changed my brake fluid. I didn't remember the exact pins that I jumperon on the connector, but others are indicating the the instructions Paul wrote worked for them, and my symptoms were the same, so I'm pretty sure this is the same thing that I did to get my brakes working properly after the fluid change.

 

Thank you for the jumper fix BTW don't count with the clip you can cause a short!

 

Paul, we recently did some work on our 2002 Prius, including changing the brakes, and have encountered the same problem (ABS light + brake light).

Any idea of whether your solution would work for a 1st gen Prius?

 

I have a 2007 that the ABS light came on about 100 miles after getting the brakes done at the dealership. They tell me now that I need to replace the ABS actuator and want $2500 for the job. They say the part is a dealer only item and costs $1700 plus $800 for labor. My Prius has 190K miles on it. Can anyone recommend another approach? I want to keep this car but not for $2500! PLEASE advise.

 

You can fit a used part from a breaker this will be much cheaper. If you put your location in your avatar we can probably recommend an independent in your area that will be cheaper.

John (Britprius)

 

Well I did my brakes, tried to clear the codes using this method and things seem to have went wrong. Now the power button keeps coming on like it's trying to reset without me even pushing the button. It's acting very strange... obviously, can't get it started now.

I checked fuses and couldn't find anything. I disconnected the battery for now since it keeps trying to power up on it's own.

Is there a way to reset the system? Any ideas?

 

1. The 12V battery should have been disconnected prior to working on the brake system, to avoid having the skid control ECU log DTC while this work is going on.

2. You should have limited your efforts to replacing front brake rotors and pads and rear brake drums and shoes. The brake hydraulic system should be left undisturbed, this means you must not open any bleed valves at the wheel cylinders. Use a C-clamp to push the brake caliper piston back into the caliper, to provide sufficient space for the new pads to be installed. Keep an eye on the fluid level in the brake fluid reservoir and remove excess fluid with a clean rubber squeeze bulb, if needed.

3. What is the voltage across the 12V battery when disconnected? It should be 12.5V or better. If not, charge the battery now, while it remains disconnected.

4. After doing #3: if you've tried the pin 4 to 13 jumper wire on the OBD-II connector and found that doesn't work, then you'll need to seek professional assistance or else see #6 below.

5. If you allowed air to enter the hydraulic system, despite #2 above, then you'll need to seek professional help to bleed the brake system or see #6.

6. Acquire mini VCI (Toyota Techstream clone) and subscribe to techinfo.toyota.com so that you have access to factory repair manual info about how to do the brake hydraulic line bleed process. However, there are issues with mini VCI relating to a possible trojan in the software, use at your own risk. I've recently posted on this.
MiniVIC . . . may have a problem | Page 3 | PriusChat

 

Thanks for this

Yes - I disconnected the battery, and only did front pads and rotors without bleeding. I also left the brake fluid cap off to allow venting, though the fluid level barely rose (if at all). I'll check the battery tonight after work.

You seem confident that this is a line bleeding issue, though it seems to me that it is electronic? Note the abs lights etc aren't even coming on any more at all since doing the pin, though they did at first. Would the pressure sensors cause system malfunction beyond the abs light? I'm just trying to run all checks before I resort to a likely very expensive assessment and repair of a possible short from the obd2 bridge.

Thanks again!

 

If the ABS lights are off then it sounds like your jump of pins 4 and 13 was successful. Do you believe that you had shorted the wrong pins within the socket?

What are "pressure sensors"? Are you referring to the tire inflation sensors or are you referring to the wheel speed sensors?

 

It's a possibility that the SSD may have came in contact with another pin when I was connecting it - I didn't see the points made about being very careful with this until after and can't recall if I was using the SSD to count the pins or not.

I'm referring to the sensors that detect pressure in the abs system that seem to be triggered by cranking back the pistons when changing brakes

 

The brake fluid pressure sensors are part of the skid control ECU system. That ECU would potentially light up the following warning lights: ABS, VSC, BRAKE, ((!)), and traction control (the car icon over the wavy path.) So if you don't see any of those warning lights on, then the skid control ECU must think that the brake system is OK.

Within the OBD-II socket, if pin 16 (12V battery voltage) was shorted to another terminal, that would likely cause serious damage. If one of the communications signal terminals (pins 6 and 14) were shorted to another signal terminal or ground, that hopefully would not cause permanent damage.

Post #15 of the following string shows resistance checks that you can make in the OBD-II socket, if you have a digital multimeter. Note there is an error in the table, where the reference to pin 4 in the last two rows of the table should be corrected to pin 14.
My VSC light wont turn off | PriusChat

If those resistance checks are OK, then you probably did not damage the OBD-II wiring.

 

This may sound strange, but I have in the last week come across a similar situation. Try turning the steering to the strait ahead position then disconnecting the 12 volt battery for a few minutes, then reconnect.

John (Britprius)

 

Thanks all for your excellent help. John, turning the wheel straight initially solved the problem of the screens going blank. Patrick, I ordered the mini VCI cable and after an online dissertation in computer programming I got the software installed and managed the brake bleed. I wouldn't say the paid online manual was all too necessary, you just have to learn to navigate techstream and remember to pull the abs relays under the hood (see below for an overview of bleeding the brakes through techstream)

The real initial misstep that I made before doing the brakes was only disconnecting the negative terminal of the 12v battery. Needless to say, it was drained over the 5 days I spent either waiting for the cable to come in or working on it. It seems the low battery caused even more codes to come up. Once I realized there was a battery issue, I connected a 12v marine battery under the hood. This caused the ABS/ ECU codes to come back - for reference, C1259 and C1310 - because a 10v charge or greater over the system trips the ECU sensors. I switched to a low amp 6V plug in charger, erased the codes in the program, and reran the health scan and the codes are now gone (with the exception of the solar sensor code and an AC code which are possibly related to the low battery/ being in a dark garage?). The 12v was down below 8, and is now back up to around 11.

Anyways, hopefully in the clear. Should be good to go by morning once she's all finished charging back up.

Basic overview of the techstream bleeding process (from memory):

1. plug in mini VCI with power off, push power button twice without stepping on brake
2. in the techstream program, click connect to vehicle
3. run the health check to see what codes appear
4. where abs/ ecu appears in the table, click on it (it doesn't appear to be a hyperlink but it is)
5. in the left hand menu is a button that says utility, click it
6. click brake bleed, then the arrow in the bottom right corner
7. you can select bleed all where it will take you through all of them one at a time, or specify a line (FR, FL, RR, RL)
8. it will walk you through - power down, take out the relays (in the fuse box under the hood), power back up (2x button), push brake repeatedly then hold while bleeding, power back down, replace relays, power back up (repeat as needed for whichever lines you choose)
9. clear the codes (it's a box in the bottom right that looks like an eraser)
10. rerun diagnosis to make sure codes are gone
11. eat pizza

 

Thanks for the update. So was your car's problem per your post #26 due to:

1) a low 12V battery or
2) the need to bleed the hydraulic brake lines or
3) both of the above?

 

low 12v battery, but I still had to do the bleed procedure to clear the codes

 

Just a comment: I don't think that's necessary. The brake fluid reservoir is by no means air tight. The less that cap comes off the better.

 

Hi everyone! I know this is an old post, but I'm hoping that someone can clarify which pins are which before I try this.

When you say "When looking up at it…" I'm assuming that means you'll be lying on your back looking up under the dash. That would mean that you would start counting the pins while uncomfortably stuck under the dash.

I just want to double check before I go out into the hotel parking lot in the rains and short my computer… Are the pins numbered, or is there and indication of which side is up on the harness?

I'm traveling and would like to fix this before I head back out on the road on Sunday. I had to have a front end alignment done a few days ago, and after four hours of driving in a heavy rain storm I did a little panic stop in a parking lot because of an oblivious pedestrian, which seemed to stir something up with my ABS. I have the ABS, VSC, and yellow ! stuck on, but the breaks check out fine (I popped into a small garage).

Thanks in advance for the help!

-Phil

 

When you look at the OBD-II connector, you will see that is is shaped like a trapezoid. Look at the longer base of the trapezoid and orient yourself so that is at the bottom of your view. The pins along that row are numbered starting at the far right, so the pin to the far right is 1 while the pin to the far left is 8.

Then along the shorter base which is at the top of your view, the pin to the far right is 9 while the pin to the far left is 16.

 

Wow, thanks for the fast reply Patrick!

I just tried it out, but I can't seem to get the lights to go out. I suspect that I'm not getting the timing of this trick correct. Maybe I'm not understanding what "ready" mode is? I can't seem to find an exact definition, but I'm assuming that you basically start the car, i.e. put your foot on the brake, hit the Power button, then take your foot off of the break, right?

So, if that's correct, then all I have to do is pump the brake more than 8 times within 5 seconds of hitting the power button. I've done that, but the ABS, VSC, and yellow (!) come on immediately when I restart the car. They're on immediately with all the lights, then stay on. I'm guessing that if I actually succeeded in resetting the computer, then lights would have momentarily gone out with all the other alert lights, then popped back on a second later when it detected a problem.

Has everyone here had an easy time resetting the computer, or did you also have to try it a few times to get it to stick?

Thanks again for your time!

-Phil

 

"READY" means that you see the word READY on the instrument panel. That light means the car is ready to be driven.

Make sure that you have the jumper across pins 4 and 13.