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2004 MG1 Overspeed Inhibitor Relay

Discussion in 'Gen 2 Prius Technical Discussion' started by airportkid, Jun 11, 2011.

  1. airportkid

    airportkid Will Fly For Food

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    2005 Prius
    Friend of mine is having trouble that's baffled his mechanic. They think it's the inhibitor relay but the part is expensive enough they'd like to be sure before replacing it. PM me if you're an expert on this bit of electronic arcana so we can discuss by telephone - the circumstances are complex enough that trying to write it all down is excessively tedious for what we hope might be a quicker & cheaper fix than replacing the relay. Hopefully somebody on these boards knows all about this relay and its associated systems.

    Thanks!
     
    #1 airportkid, Jun 11, 2011
  2. seilerts

    seilerts Battery Curmudgeon

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    Unfortunately, this approach does not work very well here. If it is a well-known problem, someone here can help. Post as much detail as you can. The greatest benefit of this forum is that someone can post their obscure problem and then the eventual solution is available to the public. If you want someone on the phone, call Identifix.

    But, MG1 overspeed inhibitor relay? That's not anything I can find in the service manual. Are we really talking about a Prius here and not a Nissan? I don't know about anyone else here, but I'd need to see at least the potential replacement part number as well as the diagnostic trouble code and 3 digit information subcode. Generally speaking, problems with MG1 are solved by replacing the transaxle -- is this the expensive proposed replacement part? The only other thing related MG1 speed is a TSB regarding 2004/5 HV ECU where a certain combination of ICE and MG1 speeds can cause a phony trouble code, P0A7A.
     
    #2 seilerts, Jun 12, 2011
  3. andyprius

    andyprius Senior Member

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    Plug-in Base
    Not knowing any symptoms it is impossible to diagnose! However, REBOOTING often helps many problems. That is: disconnect the neg connection on the 12V for a few seconds, then reconnect. May have to be done 2-3 times and recycle power mode also 2-3 times. On rebooting sparks will occur, but don't worry about it.
     
    #3 andyprius, Jun 19, 2011
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