2010 Prius , Traction Light ON after changing the Brake Light Sensor

Not yet, but maybe after you post what the trouble codes are.

If you don't have a scan tool to get them, you can get them this way:

Blink (a/k/a Flash) Codes – How to. | PriusChat

 

And this was a new switch from the dealer You put in yourself or a switch from a car that kind of look like yours that you pulled from wherever? Yeah try to get codes. If you're going to own a Prius you might want to look into a AP200 scanner It's only about 56 bucks or so be one of the better things you purchase for a Toyota vehicle no subscription one time fee and use.

 

Well like the fellas at above A lot of code scanners don't read all the codes in the Prius properly It's a tricky situation You need to get hold of a scanner that you can use or whatever that will at least get the brake codes from your Prius I don't think that light can be on with just absolutely no codes but maybe it's possible I would think not I know in my Prius anytime traction control light or any of those orange lights are on I generally have codes pertaining to ABS VSC traction control in general of course I have a very accurate scanner several of them that can read the codes in a Prius and I've dealt with scanners that cannot I have a few over here on the shelf that don't get used on Prius but everything else pretty much so there's always that I'm going to guess you have some kind of off-the-shelf scanner from the big box stores If you didn't pay over $200 for it there's a good chance or almost a guaranteed chance it's not doing what you need it to do.

 

autel200

watch

 

If the scan tools you have won't show you the codes, you can get them this way:

Blink (a/k/a Flash) Codes – How to. | PriusChat

 

Well with those codes it can be your relay and or your skid control ECU and/or your brake booster and the brake boosters common to go on this model.

 

Those kinds of reader's-digest trouble-code cheat sheets give you such inadequate information they'll pretty much never help you troubleshoot a problem (and it's not much more help if someone basically reads you the list of possible components at fault from the reader's-digest thing you already found).

The circuits of interest, involving the stop light switch, the "stop light control relay" (which is more of an interesting electronic thing, not an actual relay), and the brake ECU (which is part of the master cylinder/booster) looks like this:



You can see how the stop light switch is an input to the 'relay' (at pin 5), but it's also an input to the ECU (pin 33, "STP"). Also, the output of the relay (pin 1) goes to the brake lights, but also to the ECU (pin 6, "STP2"). So the ECU knows when the relay is getting an input to turn on, and the ECU can also tell whether the relay did turn on. Big Brother is watching.

Also, the ECU can light the brake lights for its own reasons (using its "STP0" output, pin 3, to pin 9 of the 'relay'). Again, it can see on STP2 whether that worked and the relay turned on.

With that background, you can look at what the codes tell you:



As you can see, C1380-761 is given when the ECU tried to light the brake lights for its own reasons, but did not see the relay output confirmed on STP2. C1380-762 is given when the ECU is not trying to light the brake lights for its own reasons, but it notices its STP and STP2 inputs do not match: either the stop switch is ON but STP2 is OFF, or STP2 is ON for some reason when the stop switch (or at least the STP input) appears OFF.

The blink method only gives you the basic code; only a scan tool can also get the 3-digit INF code. Because of your recent work on the switch, I'd probably assume you have 762 here, but if you could check with a scan tool then we'd know for sure.

My guess would be something pretty simple happened while you were replacing the switch, and by knowing what this code is telling you, you'll be able to find it and straighten it out. There are seven pages of troubleshooting advice in the C1380 section of the repair manual (where I cribbed the information above) if that would help.

Toyota Service Information and Where To Find It | PriusChat

 

Readers Digest repair codes?
Big Brother is watching?

I suspect those references escape most of the crowd.

 

So what do we think happened here Just replacing the stoplight switch Nick the wire cut a wire left something unplugged?

 

That video doesn't explain any issue, it just shows how to use the jumper+pedal strokes alternative to using a scan tool to clear brake system codes. "The" issue he started with (a wheel speed sensor left out of place) was different from "the" issue you had (mismatched STP and STP2 inputs about the brake lights). The only thing "the" two issues have in common is that clearing the code makes the code go away. If you were using a scan tool, its clear-code feature would do the same.

So you had a C1380 and cleared it, and so far it hasn't come back. As long as it doesn't come back, it may have been set by something that just occurred while you were doing the work, and things are now ok. If it does come back, you'll know from #11 how to troubleshoot it.

 

That's what I figured The kid doesn't have a scan tool or the one he has is for the Chevrolet etc and I don't know how he figured this out here but whatever seems like a lot of effort for just getting a scan tool for a minute maybe clean off the ends of your wheel sensors they're magnetic crap bills up on them Little things like that A lot of people don't do any housekeeping when they're working on the car they just leave the cake to grease and all the garbage sitting there and then wonder.