Warning dashboard lights on Prius 2010

First thing to check is condition of 12V battery.

 

probably the brake actuator going out, but you'll need to read the codes

 

I've had brake warning lights, coupled with weird brake feel. The brakes worked, got you stopped, but definitely did not feel normal, lacked modulation. I also had "CHECK HYBRID SYSTEM" warning.

In my case it was apparently to constant connection of a ScanGauge to the OBD port:

I had 3 instances thus, and each time brought it to the dealership, had it checked over, codes read and dismissed. Everyhing would go back to normal, then a year, a month, and finally a week later the problem would come back.

The last time, the mechanic showed me how his Techstream connection was dropping, every time he wiggled the cable, and speculated the SG connstant connection might be the culprit.

I took his advice, that was at least 4 years back, no further occurrences.

Your case sounds simliar, but no "CHECK HYBRID SYSTEM" warning. Still, might just be an electronic communication problem. I would take it in to dealership, have them read the codes, see what they say. Around here that typically costs $75.

It might be the accumulator going, it could be electronics, either way you get the ball rolling.

 

Some folks, ya say your back hurts, they tell you it's probably cancer.

Yeah, read the trouble codes. That's what the warning lights mean, by the way: read the codes. There are too many possible issues (around a couple hundred that the brake ECU can detect), so it's not like they can put enough lights on the dash to tell you what's up with the car. They put lights there so you will read the codes and look them up in the repair manual.

There is one computer in the car that coordinates several different functions: the electronically-controlled braking (ECB), the anti-lock braking (ABS, when you're trying to stop and wheels slip), TRACtion control (when you're not trying to stop, and wheels slip), and vehicle stability control (VSC, when there are skid-inducing forces on the car and strategic braking of certain wheels can help cancel them). In a way, those are separate functions that share a lot of data and happen to run on the same ECU. They have their own sets of trouble codes, and they light their own lights on the dash. But they also gossip a lot, which means any time, say, the ABS logic stores a trouble code, you'll almost certainly have an ECB code that means "hey did you hear ABS stored a code?" and a VSC code that means the same thing, etc.

Hence it isn't unusual at all to get those warning lights coming on together. Once you have read the codes and sorted out the "hey did you hear?" ones, the remaining ones indicate where to start looking for what's up with the car.

 

Chapman F
How do we get to see these trouble codes?
Is there an OBD reader that we can trust?
I have a HV charging problem but no idea why!

 

You can get a bluetooth dongle and use a phone app (I use carista) to read the codes, you could check with autozone or similar to see if they could read out the codes

 

This points to the hybrid battery going bad. I have the very same issue. It is the hybrid battery.

Posted via the PriusChat mobile app.

 

It isn't possible to say person A and person B have the "same problem" because they have dash lights lighting up.

Behind those dash lights are trouble codes that can be retrieved, amounting to hundreds of possibilities.

In the original post of this thread, there is nothing described that points to the hybrid battery specifically.

This thread's a few months old now, but anybody with similar dash lights or symptoms should simply collect the trouble codes, look them up in the repair manual (more info) or post them here, and troubleshoot whatever problem their car is really having.

 

With those lights on, the regen of the hybrid battery will not happen and the battery will fail.

Posted via the PriusChat mobile app.

 

Given the lights in the original post, there is no indication of any current problem with, or risk to, the traction battery. Even when the brake ECU disables regen for most reasons, regen braking is certainly not the only way the traction battery gets charged. The engine will run and charge it just as in any other circumstances. Unless there is a battery-specific trouble code indicating otherwise.

Dire prognostication without knowing the trouble codes won't help anybody. Reading the trouble codes will.