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Master Warning, ASC, Hybrid System Warning light on 2007 Prius

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Axekicker, Jul 22, 2016.

  1. Axekicker

    Axekicker New Member

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    Did all your warning lights go off? Mine did. I was driving on the highway and pretty much every warning light went off. It was like the space shuttle crashing back to Earth. Freaked me out. Cruise control stopped working also. But I was able to get home safely. I found similar posts on Priuschat, saying that it's probably the inverter coolant system failing. So first, I tried AAA just to see if the guy would know something, but it was way over his head. He did notice my aux battery was failing, but not much else. Then I found a service online that comes to your place to do the work, and they sent a guy out on a Saturday for $70 and he read the codes, and did a full visual inspection, and yes, something was up with the cooling system. He suggested I have the dealer look at it because flushing the system is VERY important apparently. Should be done every 50,000 miles. I had no idea. I was so worried it was the hybrid battery; we all know what that means! So I had the car towed to the dealer (don't drive if your Master/Hybrid light comes on!) and they said, indeed, the pump was gone. And, of course, they found a number of other things included the dying aux battery. It took them 4 days to get the damn part in stock. At least they covered the car rental for me. Fixing both was $600. They also said I need spark plugs and something to do with the fan ( don't have it in front of me). But I will the online service do a quote as well. Not to be shill or anything, but my first experience with them was great since they came out on weekend, and it was half the price of having the dealer run the codes. And it gave me the info I needed to take to the dealer so I wasn't going in blind. They come to your place and do the service there. I highly recommend it for basic stuff. And they were honest enough to tell me to take it to the dealer for the repair. Also got $10 off next service. Dealing with car repair is SUCH a hassle; it's about time something like this existed. Message me if you want the name. Anyway, shout outs to Priuschat also for cluing me in to the issue!
     
  2. JC91006

    JC91006 Senior Member

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    Most likely the inverter pump had failed. I had a friend that had this happen. All lights went off after a little while (I guess when the car cooled).
     
  3. Axekicker

    Axekicker New Member

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    Yes, it was the pump. Appears to happen to a lot of people with an older Prius.
     
  4. JC91006

    JC91006 Senior Member

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    so even after the recalled electric pumps, they still fail.....so it was a wasted recall
     
  5. ericbecky

    ericbecky Hybrid Battery Hero

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    Unfortunately I still see plenty of pumps that fail over time.Just had one that was replaced within the last two years that failed again.
     
  6. bisco

    bisco cookie crumbler

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    might depend on how hard you drive it.

    anyone who said flushing the system every 50,000 miles is very important, would be flushed from my system. not only is it unimportant, i've never heard of it in 11 years.
     
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I am on the third inverter coolant pump with the 2004 (221K miles). The original was replaced as a preventive measure by me prior to the recall taking effect, ~90K miles or so. The second pump didn't last as long as the original, 40K miles or so, and was replaced under the recall. The third pump is still working well...

    The factory fill coolant has a 100K mile service life. Subsequent fills have a 50K mile change interval. It is not necessary to "flush" but it is necessary to periodically drain and replace the coolant.
     
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  8. bisco

    bisco cookie crumbler

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    would you say the old coolant was the cause of the pump failure?
     
  9. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Well, considering the G3 Prius has a 150K service life on the factory fill inverter coolant, I would say that changing the inverter coolant is not a terribly high priority compared to other maintenance that might be needed. I don't believe the OP indicated the odometer reading of his car.
     
  10. JC91006

    JC91006 Senior Member

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    I wonder why the gen 2 had a 100k miles service life in the coolant and gen3 is 150k. Maybe this could be a lifetime fluid?
     
  11. bisco

    bisco cookie crumbler

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    or maybe they just finished a study showing the longer interval wasn't a problem. couldn't be marketing like engine oil, who would know or care?
     
  12. andrewclaus

    andrewclaus Active Member

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    This would be my first guess. Second is that there's better metallurgy at work in the inverter, assuming the chemistry of the coolant is the same.