Gen 3, 2010, Traction Control, ABS, ECB and Brake lights on

Discussion in 'Gen 3 Prius Main Forum' started by yak76, Feb 1, 2025.

  1. yak76

    yak76 Junior Member

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    I had these lights come on. Not sure yet if regen is affected as I was in a rush to get to work in the morning. Browsing through here, it seems like I should short CG/TC pins on the OBD II and read the codes. I do not have the manual to match up the codes, however.

    Can some gentle soul point me to a link or give me a PDF to refer?

    I did have the front brakes done last month so will be checking there as well.
     
  2. yak76

    yak76 Junior Member

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    OK, got back home last night and shorted the pins - getting Traction - 43, ABS - 34 and ECB - 36. Browsing threads here seemed to be the LH rear ABS sensor. C0215/34.

    Took the wheel off and the wire looked good, tried wiggling and tapping hoping that would do it but no go (short drive after, lights remained.) Also checked the repair manual and it has the 6 possible reasons below for C0215/34, with the first 5 pointing to the hub.

    I'm thinking I'll try changing the LH hub as a first course of action. Can someone advise on best place to procure?
    Amazon has hubs starting at $45 which I don't trust. it's cold here so I might have the local shop do it - I worry that I won't be able to get the old hub off, worse, get stuck doing it.

    I also wonder how long I can drive in case its something more serious like the Brake booster thingy...

    ---
    C0215/34 - Rear Speed Sensor LH Circuit

    1. Open or short in speed sensor

    2. Improperly installed speed sensor, or abnormal clearance between sensor and rotor

    3. Open or short in wire harness

    4. Improperly connected connector, deformation or corrosion of terminals

    5. Rear speed sensor LH

    6. Brake booster with master cylinder (Skid control ECU)
     
  3. MAX2

    MAX2 Active Member

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    Why change the hub if the fault is in the sensor circuit?
    Inspect the sensor, its connector, and the wiring to the sensor.
     
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  4. yak76

    yak76 Junior Member

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    I did inspect the connectors and wiring - looks good. How do you inspect the sensor? Isn't it built into the hub?
     
  5. MAX2

    MAX2 Active Member

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    Checking electrical parts is done according to the manual using measuring instruments.
     
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    The rear speed sensor connectors are a real pita to disconnect. We had a rear axle replacement (way back), and I noticed more recently the driver's side connector lock mechanism was broken, likely by the body shop's suspension sub-contractor. I looked at the other one for comparison, and managed to break it as well. So for ours now both rear connectors are held in by friction only. And so far no problems. But something to check.

    I've also seen South Main Auto videos: if he's got an issue with one side, he'll run jumper wires, to effectively reverse their signals, and see if the code follows.

    I've also read more than one rear bearing replacement story, where the speed sensor connector was so troublesome they left it connected while banging on the bearing, and when bearing finally came out the harness was torn.

    Definitely leave bearing replacement to the last, especially in New England: it's reportedly a fight (never had to one personally).
     
  7. Jossa

    Jossa New Member

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    Hi @Mendel Leisk , your posts have been incredibly helpful on all the threads I’ve looked at. I wondered if you might be able to spare a moment with a concern I’m having? I’m new here and couldn’t figure out how to message you directly, I’m sorry to put it here on this thread.

    I’ve been getting the ‘death rattle’, big shakes, on my 2010 gen 3 combined with loss of coolant. I’m trying to stay optimistic and hope for it not to be the head gasket. With that in mind there are some curious symptoms that suggest it may NOT be head gasket:

    1. No white smoke out of exhaust
    2. No milky quality to oil on dipstick
    3. No light coming up for engine/coolant overheating

    I’ve read and seen videos suggesting it can be a few other issues potentially that sync up with these symptoms:

    1. Egr and manifold need to be cleaned (would this account for coolant loss though? Could it be a combination of this and something else ie possibilities below)
    2. Coolant leaking into exhaust via heat exchanger on the catalytic converter
    1. Water pump leak
    • I understand if this is the case people also recommend replacing the thermostat?
    1. Hidden hole in the tubing. This I confess I understand the least - maybe the person is referencing their water pump also? Here’s the Reddit link to their thread if it helps
    2. Burp it/bleed it - to remove air bubbles which may be creating shaking feeling in car - seems least likely? Any correlation to coolant loss?

    My thoughts at this point are to do a basic test for head gasket issues to better rule that out or in. I’m not that handy with cars, so after going through the options of combustion test, compression test, leak down test, it seems combustion leak test is most user friendly for my skill level.


    I’ve read a failed combustion leak test won’t differentiate between a busted head gasket, cylinder head or a cracked block, but for my purposes that seems okay because if it’s either of those which as I understand it are major/expensive damage, I will just go with the option of cutting my losses and getting a second hand motor replacement.


    All said and done, I’m holding out hope I can remedy this with an egr clean, water pump change or tackle coolant leak into exhaust. First I want to rule out major damage of busted head gasket or cracked block.


    Two main questions I want to ask you:


    1. will combustion leak test be adequate to test for the major damage described above (given my very limited skills with cars)?

    1. If you have to put your optimist cap on, which alternate solution, other than a head gasket problem, seems most likely to you, given it’s the combo of shakes and loss of coolant, but the lack of other busted head gasket common symptoms?

    Thank you for your response,


    Josh
     
  8. yak76

    yak76 Junior Member

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    @Mendel Leisk thanks for the south main auto pointer. I found the video. That solution is genius. If it was summer I’d be all over it, and do it myself. Regardless, it gives me something to discuss with the local shop.

    Overall the car seems ok to drive. No regen so poor mileage, and no abs obviously but that can be endured. The bigger concern is the inspection coming up for March and if the repair is not a reasonable cost it will be curtains for this one. Sinking more money into a 14yr/170k car is folly.

     
  9. Mendel Leisk

    Mendel Leisk Senior Member

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    @Jossa I’ve sent you a private message.
     
  10. Mendel Leisk

    Mendel Leisk Senior Member

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    @yak76 do you have anything constantly plugged into obd port?
     
  11. yak76

    yak76 Junior Member

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    I do not, sir. Why’d you ask?
     
  12. yak76

    yak76 Junior Member

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    Just wanted to leave this here for closure - the shop in my town replaced the rear left bearing and all lights are off. Back to normal I would say with regen abs stability control working. They would only use their parts though, and 2 hrs labor, so out $550.

    But I have functional transportation back.
     
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  13. Mendel Leisk

    Mendel Leisk Senior Member

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    I had similar symptoms with a ScanGauge II constantly plugged in. Apparently the plug and cord weighing on the obd port was the culprit. Dealership mechanic noted his techstream-connected laptop was losing connection if he tapped it. He suggested to cease using the SG and see if it helped. It did: no more occurrences.

    The "symtoms" were:

    pretty much same lights as your case, plus "CHECK HYBRID SYSTEM" notice, and brakes felt odd, at first like they were not working, then seeing they're working but taking more effort, not as linear.
     
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