Red Triangle but nothing is broken, 2004 Prius 220k miles

Hi ,

That light is on because the car has information to give you about a problem. It's very enterprising of you to have done all of the other stuff you've already done before getting the information the car is trying to give you, but it's important to get that information. Without it, there's no good way to help much.

A lot of people here buy a J2534 dongle to connect to a laptop and use Techstream software to connect to the car and get the info. It's not the only way, but it's the most sure-fire way, using the same software as at the dealer.

If you don't want to fuss with that, you can always visit the dealer and have them retrieve it. They may charge for half an hour or an hour of shop time. Not pennies, but it also saves you some fussing around getting Techstream set up if you don't have it already, so sometimes it's just the easiest way to go and gets you the information the soonest.

-Chap

 

p-lock is problematic

 

weak 12 volt battery.. most common cause

 

nothing worse than a locked up P when you want to use it.

 

There IS something wrong, you just haven't found out WHAT yet.
And what exactly leads you to believe that they battery is "in normal shape" ?

I think you need to scrape together $100 or so for a "diagnostic" visit to a dealer.
Or you can just keep driving it until it stops......and then spend a LOT more than that.

P.S. The answer to everything is NOT to be found on the Internet.
And often the answer you find is not right.

 

When it throws a Master Caution RTOD it’s not kidding.

Don’t be surprised if it leaves you on the side of the road when your least capable of dealing with it.
Then it gets extra expensive.

An RTODs do not go out unless cleared by OBD or the 12 volt battery is removed or went dead.

 

I'm not certain that's true for all possible causes that can light that light.

I know I can't singlehandedly get people to quit melodramatically calling it the "Red Triangle Of DEEEAAAAAATTTHHHH!!!!" but, honestly, people, Toyota calls it the master warning light. It comes on when some computer in the car wants to tell you something. There are a couple hundred possible somethings. Some may point to a big ticket repair and some only to something you can straighten out with a little bit of investigation and attention.

When it lights up, you just find out what the car is trying to tell you, and go from there.

Some particular trouble codes are more 'sticky' than others. Some actually will reset if the
condition that triggered them is not detected again during n subsequent drives. If such
a code was the only one behind why the MWL was on, I would not be surprised to see
the MWL go away when the code does.

That's good news if all you care about is the light being off. It's bad news as far as finding
out what the car was noticing, because now you have to wait for the next time it notices.
Then you can just find out what it's yapping about, and post here, and we'll talk about it.

-Chap

 

I was not talking to you. I was talking to the op and like most posters we see are pretty clueless.
I prefer to scare them a little so they can find out why there car is throwing the master caution light.


Advice from you is don’t worry about it. I hope the op Takes your advice.

 

Sorry Ed, didn't mean to come off as undercutting what you were saying. The part I was unsure about was just the no-RTOD-ever-goes-away-without-action part. I had not heard that before, and am not sure that it's true for all cases.

I understand wanting to give the poster a good nudge to find out what's up. I try not to exaggerate for the sake of a nudge, though, because that sometimes backfires. If I say "this light being on will always kill your gerbil" and then you get home and the gerbil's fine, you might take the next thing I say at a discount.

For the sake of clarity, I am certainly not saying don't worry about it. My advice is to treat it absolutely seriously, meaning, proceed immediately to asking the car what it is warning you about, and using that information as a start on identifying the issue.

What I advise against is just seeing the lights on, collecting no information, and immediately assuming the most expensive possible thing just happened, when that's a possibility out of a hundred.

The easiest way to turn a fifty-cent repair into a $2000.50 repair is to see the warning lights, jump straight to the conclusion it has to be the $2000 thing, replace that, then say "bother, why are these lights still on?", and then get serious about problem diagnosis and find the fifty cent issue and fix it.

-Chap

 

Public posts are talking to EVERYBODY.

And that second sentence is just crabby, rude and unnecessary.......like we usually get from you.

That's worse than clueless; you should know better.

 

Umm ... I don't think I've ever perceived Ed as being usually like that ... which was why I was sorry I may have inadvertently given offense.

-Chap

 

Well, same with me too. I have never come across such an acronym before.RTOD?

 

A lot of people call the master warning light either the Red Triangle Of Deeeaaaattthhh or the Red Triangle Of Doooooooommmmmmm, I guess because it's fun and sounds dramatic, but sometimes they get carried away with the drama of their own name for it, and forget that it's just a light to let you know you should read some trouble codes and not procrastinate about it.

Anyway, in my Gen 3 I think it's yellow.

-Chap

 

And I apologize for being snarky. I retract my statement. Your posts are usually spot on.