Got the 2010 Prius back from the dealership (they did an AC compressor inspection). On the way home, the Prius did something it never has done before: A large yellow triangle, with (I believe) an exclamation point inside, momentarily turned on just above the READY indicator on the left side of the dashboard instrumentation. A tone (beep) was emitted at the same time. It came on for about a second, and then went off. It was not the TPS sensor indicator. The circumstances were that we were exiting the highway at about 50MPH, making a gradual right turn at an angle of about 45 degrees. We've done that turn hundreds of times before without any lights coming on, or tones being emitted. The pavement was dry, and there was no significant wind. Afterward, we tried to replicate the circumstances, and the light came on again, with the tone. What is that light, and what does it mean? Why would it flash on now, given that it has never come on before? We're going to hook up an OBDII scanner and see if any codes have been thrown. To our knowledge, the only unusual thing the dealership did was run the AC on full for over an hour with the car parked.
is the icon in the o/m? all the warning lights come on for a minute when you boot up, it's part of the self test process.
My guess: Low oil level. Between the attitude of the car and the turn the oil sloshed away from the sensor and triggered the light. Is the dipstick dry?
BINGO! You win. Well, most likely (see below). Shortly before we read your post, we decided to check the dipstick: bone dry. It's amazing that the Prius just spent 5 days at the dealership and they never checked the dipstick as a courtesy. So now, the question is: did the technician who performed the last oil change ~2000 miles ago "forget" to add enough oil... or do we have a leak... or are we burning oil? No evidence of a leak on the ground. No plumes of smoke out the exhaust. A kind friend delivered some 5W20 Mobile 1, and it took about 3 quarts to get the dipstick to the midpoint between the two measurement dots. Is that the correct level? We previously had 0W20 Mobile 1 in it... so now we have a bit of a mix of 0W20 and 5W20. Is that ok until the next full oil change? We just drove the vehicle about 80 miles and the warning light never came on, so that most likely explains it. What's also weird is that the oil level was under 50% and the light only came momentarily during a couple turns.
Without checking your oil frequently the first question is an unknown. If it’s a 2010 and high miles oil burning is a well known issue. Im not sure in fairness why they’d check your oil if it’s booked in for ac. They probably assume the owner checks every now and again. The issue now is if you’ve had to put that much in to get it to the halfway point there was probably between 0.5 to 1l left in there. The mix of oils will be fine.
Dealers here usually do a fairly extensive check, hoping to make a service sale. The shop I use checks oil level and other fluids, looks for leaks, and other basic stuff. Unfortunately, when I took my wife's Prius in for a recall on the steering, they rotated the tires while they were at it ... two days after I rotated them. So, to me, it does seem odd that your oil would be so low right after service. But then again, standard procedure is to check it every time you get gas. That 5W20 oil might actually help you burn less since, I'm pretty sure that's what's going on. Keep a close eye on it.
Thanks for your reply! It's a well known issue? That seems like good news. It's a 2010 with over 125K miles, so that seems like fairly high mileage. Is it simply a common practice to put in a half-quart every month? What is the appropriate level to fill it to on the dipstick? Half way between the first and second dot, or all the way up to the second dot?
Anywhere between the dots is "good enough" but since you are there might as well get the level closer to the top. At least you won't have to add as much "next time". The dealer's employee may have checked the oil or may have simply checked the box on the list. I've had tires grow tread and the tire pressure recorded at factory spec. When I checked the pressure sitting in the lot I was relieved to see it was "normal". I want to believe the employee was accommodating me by not deflating the tires and not triggering grief from the boss.
solid YELLOW TRIANGLE.....however, the light did go off after I pulled over and checked oil and got back on the road.......hmmmmmm So, this yellow symbol just happened to me this morning, 30 mins into my drive....(I had just changed oil yesterday)....so, I had all sorts of images flying thru my head of oil filters falling off....or the oil plug leaking.... I pulled off to a gas station and everything checked ok....dipstick had oil....filter and plug both intact.... Started back up and no yellow triangle... now this kinda leaves more questions than answers.
I wish all the questions here have the same particular description as yours with weather conditions and so on. You never know what is goin on and why