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After adding fogs --- get "check hybrid system" error

Discussion in 'Prius c Accessories and Modifications' started by tahoeRon, Jan 27, 2013.

  1. tahoeRon

    tahoeRon Junior Member

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    I added fog lights, and I removed the fuse box and body computer to do so. I disconnected the 12V battery for most of the work, but later I did pull a couple of under-the -dash connectors with the battery connected.

    Now I get the screen saying "check hybrid system", "don't drive". I've tried the turn-the-key-on-three-times technique, and I disconnected the battery for 30 mins. Still the message persists.

    Using my Torque app, I can clear the ECU fault and the message disappears. However, when I start the car the next time, the message is back. Everything else seems ok.

    I checked all the cabin fuses and most of the engine compartment fuses. I took everything apart again, and double checked the fit of all the connectors under the dash. It seems that I have thrown a code which keeps popping up every time I turn the ignition on.

    Is this something that only the dealer can reset. Will it possibly go away after a few more days. Any suggestions?
     
  2. TxTkd

    TxTkd New Member

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  3. tahoeRon

    tahoeRon Junior Member

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    Nope, I already read that, and I searched the forum for other solutions. I never touched the HV battery. The car starts and runs normally.
     
  4. kwhubby

    kwhubby Junior Member

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    tahoeRon, I believe we were discussing the wiring in the big thread a while back. How exactly did you end up doing the wiring? Did you connect the switch directly to the computer pin 13, or did you bridge pin 27 and 13 inside?

    I recall having this light come up when I was first testing out things. Interestingly, after a day or so it just went away. At the time my test wasn't producing any results, I may have actually been testing pin 27 at the time.

    I was really alarmed when I saw the message, but when it went away I wasn't able to conclude what had caused it.
     
  5. tahoeRon

    tahoeRon Junior Member

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    Kwhubby, yes I connected to pin 13. I double checked with an ohm meter that I had not shorted to any other pins. The fogs are working just fine.

    By the way, the two blue wires: only one goes to the fog lights. I don't know where the other goes, but I connected them together to the fog relay plug.

    The message has not gone away after several trips. It comes on whenever I first turn the ignition on. I then can clear the ECU codes with the Torque scanner (even though my scan show no ECU codes were thrown), and the message disappears and does not show again until I start up again.
     
  6. kwhubby

    kwhubby Junior Member

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    Interesting about the two blue wires on that hard to reach plug, which one goes to both fogs (outside or center blue wire)? I should correct my installation/instructions.


    Also, your fog switch only pulls down pin 13 to ground correct? Off should be floating, not +12V.

    I would probably try disconnecting harness taps, and removing the relay/computer assembly again.
    This time don't disconnect the battery at the source, try disconnecting the front connectors, the large front 12V connector, followed by the rear connectors.
    While you have it open you could disconnect the pin 13 tap, or at least carefully make sure it absolutely can't short out anything when the wire is compressed or torqued in the case- you wouldn't be able to test all the pins once the box is closed. Make sure there isn't some loose piece of metal or something floating around.

    Does the light still occur when you have effectively undone all your modifications?
    Can you try not using App to reset the code, and just drive it for a couple days and see if it goes away on its own?
    Can you reset the system?- I believe I've read about ways to reset the whole system, and I seem to recall wondering about a reset switch I noticed near the cabin fusebox.
    Finally, I hope you didn't zap the computer module with static electricity (basic ESD safety)? - the relay/fuse board wouldn't be sensitive once disconnected from the computer module.
     
  7. tahoeRon

    tahoeRon Junior Member

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    Thought it was fixed today, but it wasn't. I bought gas and started up. No "check hybrid" message for the first time in several days. However, it was back next time I started. Once I turn the ignition on and clear the ECU message, I can drive any distance without the message coming back.

    kwhubby, yes pin 13 floats when it is not pulled down. I don't think I made any wiring error and I have electronic experience. I took everything back out (quite a pain in the nice person) and looked for any problem and found none. Pretty sure nothing got "zapped" by static electricty.

    I think the reset switch near the fusebox is for the tire pressure reset. I don't remember which blue wire went to the fogs, but I tested with an ohm meter and noticed that only one responded.

    I really believe that everything is A-OK, except I can't clear the "check hybird" message permanently. It is so anoying that I hesitate to drive around with it on, but I might try it if nothing else is suggested.
     
  8. KK6PD

    KK6PD _ . _ . / _ _ . _

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    I would take it to the dealer with your mod off the car and see what they say.
    Hopefully they do not read Priuschat.com!

    Let us know what they find!
     
  9. kwhubby

    kwhubby Junior Member

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    I hope you can figure out something conclusive. Now that you mention it, the time I saw the light come on- it went away after filling up gas and never came back. I had believed the light came on because I had accidentally toggled the wrong pins. It was a few restarts later before I had a chance to fix my first attempt.

    If everything was done right, all is secured, and driving it around for a while doesn't just clear it up (without interaction), KK6PD suggestion seems like the next logical step. It is a big pain to take things apart again, I think I took that interior fuse-box assembly out and apart at least 4 times.
     
  10. tahoeRon

    tahoeRon Junior Member

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    I have my one year service coming up in five weeks. If nothing is resolved by then, I will let them look at it.
    My only reason for posting here was to see if anyone has the sufficient technical know-how or info to tell me what's happening. Appearently not.
    By the way, I am not trying to hide my fog light installation from the dealer.

    What I was looking for is something definitive like:
    (a) Only the dealer can clear this, even if there is no problem now.
    (b) It will go away by itself unless there is a problem still.
    (c) The technique to clear this is ... (something I haven't tried).
     
  11. wmo168

    wmo168 Member

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    Any updates on this?
     
  12. ursle

    ursle Gas miser

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    This sets off red lights for me, you have an electrical gremlin.... and you have an unidentified blue wire hooked into the circuit, I'd unhook the unidentified blue wire.
     
  13. ROLOPR

    ROLOPR Member

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    kwhubby can you tell me where does this computer pin 13 and 27 is located (if you have a pic of this pin better)
     
  14. kwhubby

    kwhubby Junior Member

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    Unfortunately these pins are only located on the connector between the main body ECU and the relay/fuse box. Normally in the upper trime levels the ECU should functionally bridge these two pins, but unforunately it does not.

    You must seperate the two units (they are attached as you can see the black box on the cream colored box: http://kwhubby.com/foglights/rearfusebox.jpg).
    Since you won't be able to crimp to these connections, soldering the pins together with a short wire inside the relay box (cream colored one) seems to be the only reasonable option. Here is the picture of the connector on the pcb board removed from the cream colored enclosure:
    http://kwhubby.com/foglights/computerheader.jpg

    I did not open the main body ECU to see how it was built, but it's possible a depopulated part may be responsible for this- in which case another solution might be to repopulate the ECU board. Due to the fact that having various population configurations on a board costs more money- and the relays were not depopulated, I'm more likely to suspect a software tweak from toyota is to blame.
    It might be eaiser to only remove the ECU in order to make this modification, if I get the time I may investigate this further.