Suddenly hit with multiple warning lights!

I drive my 2005 Prius 40+ miles each way for my commute. I bought it in the fall of 2007 with 56k miles already on it, and with my commute I'm up to 140,000 miles already.

This morning I was about 5 minutes from work, cruise control on, and deeply absorbed in listening to a podcast. I was startled out of my reverie by several things happening simultaneously. The car beeped, the cruise control kicked off, and multiple warning lights lit up on the dash, with a warning icon of some kind also on my MFD.

(Once stopped, I looked up the warning lights. They were: Master warning light; Check engine light, or "malfunction indicator lamp", according to the manual; YELLOW Brake system warning; VSC warning light. On the MFD, the Hybrid System Warning Light was on.)

I was on the highway doing about 70 and I had just crested a hill, so I allowed the car to coast on the downside while trying to assess the situation. I cautiously pressed the accelerator, and though the road noise made it impossible to hear the engine, the car seemed to still be driving normally. The Energy Monitor still showed normal flows between battery, engine, and wheels. I had one final, short uphill climb before my freeway exit, so I chanced it. I took it easy and allowed my speed to decrease on the uphill so as not to push too hard, just in case. Once off the freeway, most of the remaining mile is downhill or flat - I can often make it to the office without the engine, and in fact I did so this morning.

Once at the office, I put the car into Park and grabbed the manual so I could identify all the warning lights before powering off the car. I turned off the Prius, let it sit for 5-10 seconds, and powered it back on. The brake system warning and VSC lights did not come back on - only the master warning light, and "check engine" lights reappeared, and "Problem" on the MFD was again replaced by the Hybrid System Warning icon. After the usual 10 seconds, the engine started normally and responded to the accelerator.

One additional note:

After the freeway exit, my car is usually at 1 green bar or just below on the hybrid battery. Immediately following the freeway exit is a steep downhill that usually puts the SOC to completely full. That was the case again today, and as often happens, that full charge was able to take me the rest of the relatively flat, distance to the office at my usual 25-35 mph. I mention this because whatever might be setting off the warnings, the Prius still seems to be managing the charge level normally; at least in the admittedly short period I was able to observe it after this occurred.

I'm a bit freaked out, being out of warranty and not knowing how bad this could be. I haven't called the dealer yet this morning because I want to be armed with as much knowledge as possible before engaging them. Based on other form members' experiences with dealers, it's apparently possible for the dealer to be even less informed than the car owner, if the dealer is lousy - and I don't know enough about my dealer to know how much I can trust them. Better safe.

So - any ideas? I've been trying to think of a single point of failure that could cause all these different warnings. No clear thoughts on the matter yet, except for the 12V battery, which I'm going to go test now.

Thanks for all responses in advance. This community rocks!

 

Follow-up: Just tested the battery. It reports 12.5V in ACC. Powered on, it dropped only slightly (I think 12.4V) - still strong. In Ready mode, went up to 14.1V. Everything indicates it's right where it should be and going strong. I tested a second time and placed a load on it in Ready mode by turning on headlights and rear window defrost - dropped to 11.4V, also where expected based on what I've read here.

I was kinda hoping the battery was the problem since it's an easy fix and known expense, but the battery seems to have exonerated itself.

Damn.

 

Thanks to USBSeawolf2000 for the quick reply and excellent video, and to Patrick and derkraut for the confirmations. I've checked the reservoir level - it's below the "full" line, but appears to be just above the "fill" or "low" line, though it's hard to tell (some kind of seam in the reservoir is preventing a clear view). With the car powered on, and the cap off, I see no movement in the fluid - it doesn't appear to be circulating. I hear a whine, but it doesn't sound like a running pump - it sounds more electrical in nature - perhaps like a pump that's getting power but has seized and is not moving?

My main concern and question at this point is whether the approx 7 minutes it took to complete my drive to work might have already caused inverter damage. OAT was probably 65-70 degrees. Note from my original post the heavy regenerative braking and electric-only operation over the last five minutes of my drive. At the time I was happy the engine wasn't used much, fearing an engine mechanical problem. Now I'm wishing the engine had been used more and not hit the inverter so hard.

 

Yeah, the fact that I rolled into work just fine gives me a bit of comfort and hope. The good downhill slope is actually immediately after the freeway exit. The remaining half mile or so is mostly flat, with slight rises and falls - my battery was at 8 green bars at the bottom of the big hill, still 7 green bars pulling into my parking lot. It is usually at 7 green or 6 blue pulling into the lot, 50/50.

Insurance reimburses for towing, and DOESN'T cover auto rental if there was no "incident" or collision. That sucks.

Now my only real problem to solve is how I'll get into my house. My keys and garage door opener are all locked inside, since I programmed my car to open it. Car is going straight to the dealer, and I don't think a drive-by of my house first is in the towing budget. :-D

 

Many thanks Patrick, usbseawolf2000, and derkraut. I was paranoid about driving it any more, due to even the *possibility* that a $500 repair might become a $5000 repair. Luckily I didn't need to do the drive-by or risk driving the car. I literally just moved into my house over the weekend, and as it happened, the seller had another key she'd found that she needed to hand off to me. I had my car towed the 40 miles from work to dealer -- there was no way I was gonna chance driving it THAT far thru the Ozark hills -- and the seller met me there and gave me the key.

The punch line? I got home and found I hadn't locked the back door. Glad I didn't pay for the tow-truck drive-by or a locksmith.

UPDATE: The dealer just called. You guys all nailed it. Confirmed a failed inverter coolant pump - inverter itself not reporting any codes and apparently still fine. Patrick: my car actually never stopped operating - it was still working as I pulled into the parking lot.

Towing charge: $115. Insurance covers: $100.
1 day car rental: $35.
Repair parts: $153 pump, $20 fluid
Repair labor: $212.

Total out of pocket: $15 tow + 35 rental + 385 repair = $435.00.

I'll happily pay that vs. the 10x cost of a new inverter. <deep sigh of relief>

My rental turned out to be a 2010 Prius. I spent most of my drive down pausing and rewinding my podcast because I kept losing myself in studying the new display options and controls. I can't decide how I like the new layout compared to what I'm used to, although I've found a couple of things to like already.

Thanks for the tips about popping the hood and using a bag of ice. I'll keep that in mind the next time my inverter coolant pump goes south. Hopefully the next failure will be the *winter* of 2015.

Makes me wonder how expensive/difficult it would be to engineer a fail-over coolant pump for critical systems like this. An extra $100 or so seems like a small additional price to pay to protect a $5k component.

 

2009 Prius: yes, it was in stock. I'd originally been told by the dealer on Monday that they were pretty booked and wouldn't be able to even look at my car until Wednesday. I called the parts department on Monday and they said they had 1 pump in stock. I dropped of my car after-hours, and went in Tuesday morning to pick up the rental and set up the repair. The tech told me they'd be able to look at it the same day, and when they called me later they confirmed that it WAS the pump, they DID have one in stock, and they'd have my car ready by end of day. I'd planned to rent a car for at least 2-3 days, so this was welcome news.

My car is slightly quieter at "idle" now, with no A/C running. Can barely hear the car now.

I love happy endings too - but that's a topic for another forum... :-D

I was contacted by the dealer yesterday to be sure I was happy with my experience in their service dept. They hit me up to see if I'd be interested in trading up to a 2010. I'm considering it, since I've put almost 90k miles on the car in under 3 years. I have 2.5 years of payments left, so I'll be approaching 250k by the time its paid off. Paying a bit more for the peace of mind of a new warranty and fresh new car is kinda tempting, I must admit. Not sure yet which trim line I'm interested in - I'm just now starting to do my homework. I have the nav package and upgraded stereo in my 2005, so I don't really wanna take a step backward in features.

Glad this forum is here - this community is top-notch. A pleasure to be here.

B