The Triple Threat: Triangle of Doom, Check Engine Light, AND Brake Light

Hi all,

Hoping you guys can help me with a problem I'm having. I've searched the boards and haven't been able to successfully find a problem similar to my own, but if you know of one please point me in the right direction.

To start off, here are my car's specs:
-2004 Prius
-172,000 km
-recently changed battery (not sure if this is the 12v battery I keep reading about, but the replacement cost me $400 CAD)
-Maintenance done regularly every year (although I'm currently due for an oil change)

So while driving yesterday, my master warning light along with my check engine light turned on while I was driving. I noticed that it felt like the engine was having a bit of trouble revving up to full speed after both lights turned on. Panicked and thinking this was the dreaded triange of doom that signaled the end of my HV battery, I brought it to the local Toyota dealership. While driving to the dealership however, I noticed the brake light turn on, only to turn onff shortly before my arrival.

They charged me a diagnostic fee of $150 CAD and weren't really able to tell me anything as they could not reproduce the error and that I'd have to bring it back if it happened again.

When I got back in my car, the warning light was off and all seemed fine. The car handled well, no issues with the acceleration. I went back home (15 min. drive from the house), shut off the car and went inside to get some of my things for work. Turned the car back on and left for work only to have the both lights turn back on after roughly 10 minutes of driving. This time however, the brake light also turned on and stayed lit for the duration of my 25 minute commute. Since the warnings went on, I've noticed a VERY noticeable lack of acceleration. Basically, even when completely depressed, accelaration is extremely slow--it takes a good 10 seconds to get up to 40/50 km and the engine sounds somewhat strained. I uploaded a video to better demonstrate this, check it out here:

A great example of the slow acceleration is at the 1:23 mark of the video; once the light is green, I actually depress the gas pedal down completely, only to get up to 40 km in over 10 seconds!

I don't know if I should go back to the dealership, so far they've proven to be pretty terrible in the customer service department. Hopefully someone here can shed some light so I don't have to go in and be blindsided by their assessment. I've heard some pretty terrifying dealership stories over the years.

Any help would be greatly appreciated!

 

I'm not sure to be honest with you. How many batteries are there in the Prius? I know my mechanic recently replaced a battery in the car that ended up costing $400 CAD). If that's the one, then it would be new.




Merged.

Yeah, the mechanic who worked on it could only explain it in French so I didn't catch 100% of what he was trying to say. He mentioned there was some communication failure which prevented them from seeing the codes. I think. I plan on returning, although I just want to know the possible issues before going in. I don't feel like being taken for a ride (pardon the pun!) and the dealership so far has failed to impress.

Question for you, if my oil was low, wouldn't the maintenance required light turn on instead? I'm going to check it with the dipstick anyways, just to be sure. And I'll try to put on the AC when the warning lights are lit to see if it works, thanks for the list of suggestions.

 

Thanks, that must be what they changed then. Given that, I guess that leaves the 12V battery out of the picture.

When I left work I noticed that the car was once again driving normally. The brake light was gone, but the check engine light and the master warning light were still there. Halfway through the commute it came back on and we heard a loud noise coming from the car. The acceleration problem began once again. I just home and here's what the car sounds like on idle:

It's so loud :-(