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From these lights on console: should I take it to dealer?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Toyotally04, Mar 13, 2021.

  1. Toyotally04

    Toyotally04 Member

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    I was at a stop light when this appeared for the short duration I was driving. It only happened twice yesterday.

    Past several weeks, the maintenance light has been on. But I thought that might be related to needing an oil change soon in one month or 2,000 mi. (based on 6 month/ 5,000 mi. reference).
     

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  2. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Car needs brake service. Toyota dealer is probably not the best choice for a 2004, they're just going to tell you "everything is wrong trade it for a new one."

    There are some great hybrid-focused independent repair shops in Southern California, you've got some good options among them.
     
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  3. ChapmanF

    ChapmanF Senior Member

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    The ((!)), ABS, and VSC lights are all controlled by the braking ECU, and they can indicate problems with the brakes. But the braking ECU also has regular chats with the Hybrid Vehicle ECU and can also set those lights because of something it heard from the HV ECU. (They have these chats because if anything is up with the HV ECU so that it won't be able to do regen, the braking ECU needs to know that, so it realizes it has to do all of the braking.)

    So if you take the car to any shop worth its salt, the first thing they will do is read the trouble codes from the braking ECU to find out why it has lit those lights. If they get codes like C1259 or C1310 (which mean "I turned my lights on because of something I heard from the HV ECU"), they will of course follow up to get the real trouble codes from there. (It doesn't even always end there: sometimes the code from the HV ECU will mean "I heard something from the battery ECU" or "from the engine control module"....)

    Reading the codes is also something you can do yourself. A full-fledged scan tool that can read all codes from a Prius is very handy to have (and many threads here describe inexpensive options), but in a pinch you can even get the codes from the braking ECU using nothing but a short piece of wire, by counting light blinks.
     
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  4. Toyotally04

    Toyotally04 Member

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    Thanks for the wise advice.
     
  5. Toyotally04

    Toyotally04 Member

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    Thanks for the detailed explanation. Those lights turned on momentarily on two occasions on the same day. Maintenance light has been on for a while, as I've mentioned before.

    Today, I heard some brakes squeaking as I backed out of my garage.

    Since it's my first Prius, I'm not well-versed in how to find and choose a good mechanic. I'm always under the assumption that a mechanic will try to deceive or cheat me in some way.
     
  6. ChapmanF

    ChapmanF Senior Member

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    That's an excellent incentive to make sure you are able to read trouble codes from your car yourself, so that at least you have that much information when you approach a mechanic.
     
  7. Toyotally04

    Toyotally04 Member

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    So I used Torque Pro app AND Car Scanner app on Android.

    All I did on Torque app was click on Faulty Codes on the main page after bluetooth was connected and the car model selected.

    After the app scanned (I did this a few times), no codes showed up. Car Scanner app also had the same results.

    I did this correctly, yes?

    Would OBD2 scanners really know if there was some physical wear and tear on brakes?
     
  8. Toyotally04

    Toyotally04 Member

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    Once I connected my Torque Pro app to my OBD2, I clicked "Faulty Codes" on the app's main page. After the app scanned everything, it shows nothing wrong.

    Did I use the app right?

    Can OBD2 scans pick up physical damage or wearing of brakes?
     
  9. ChapmanF

    ChapmanF Senior Member

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    The scanner can only retrieve information from the car's computers, therefore can only tell you what the computers know about, which can only be things they have sensors for. That's not everything in the car, of course; there aren't any sensors for the thickness of the brake linings or condition of the grease, for example. That's why I physically inspect my brakes each time I rotate tires.

    On the other hand, any time the car's computers illuminate warning lights on the dash, that tells you the computers do know something about something, and a proper scanner will tell you what they know about what. If you have a situation where warning lights are illuminated but the scanner you are using retrieves no information, generally that puts the scanner you're using in question.
     
  10. Toyotally04

    Toyotally04 Member

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    Thanks.

    But it's a standard BAFX

     
  11. Toyotally04

    Toyotally04 Member

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  12. Toyotally04

    Toyotally04 Member

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    Eh... tried linking the BAFX product on Amazon.. but I don't see it on my posts
     
  13. ChapmanF

    ChapmanF Senior Member

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    People report using a lot of different scan tools on these forums, with a lot of different success rates.

    Toyota Techstream on a Windows laptop with a J2534 dongle generally retrieves all the information needed.

    I am happy when people report success using other things, but there's not much I can add when they don't.
     
  14. Toyotally04

    Toyotally04 Member

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    I'm subscribed to this popular independent car mechanic YouTuber who uses a scanner worth a few k.