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Gen 2 MFD Removal and Replacement - 12V Battery and Parking Connector

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Delegator2478, Nov 12, 2024 at 9:37 PM.

  1. Delegator2478

    Delegator2478 New Member

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    Hi all,

    Own a 2005 and I ran into loss of power to the multifunction display (MFD).

    I plan to pull it out and replace with a used unit. Lots of helpful threads on PriusChat but I have outstanding questions on best practices when removing and fully disconnecting the MFD.

    1) Should I disconnect the trunk 12V battery before disconnecting the MFD? New to the forum so I apparently can't post links, but the YouTube video /watch?v=8STVXsXpPxk (around 30 seconds) mentions disconnecting the 12V battery as a general habit:


    Is this necessary? If so, should I just disconnect negative cable from 12V battery under the right rear of the trunk? This thread indicates might run into some surprises if don't disconnect.


    2) In this thread (see post #10) someone mentions the red triangle of death coming on after they disconnected the MFD. Potentially because they disconnected the parking button when removing the air vent panel to the left of the MFD?


    Just want to confirm, should I just leave it connected when removing the MFD? What about if you also disconnect the 12V battery as question 1 asks... is this all avoided?
     
  2. Tombukt2

    Tombukt2 Senior Member

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    Nope I removed the two center vents the two 10 mm screws withdraw the MFD squeeze all the plugs leave them hanging and hopefully have the correct MFD not a base if it's not a base car going into the car and working on so there's always that the basic plugs that come in a basic Prius should be able to operate most of the MFDs realizing that a GPS MFD and all of that those functions are not going to work and the buttons will be weird so you don't want to do that if you're not well versed in some of that or you'll be having serious problems you'll never get straightened out basically without changing the MFD to the exact one you have.
     
  3. Delegator2478

    Delegator2478 New Member

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    Appreciate the response!

    Did come across quite a few warnings to not casually swap all the MFD models and full connectors. Good to get extra confirmation.
     
  4. Tombukt2

    Tombukt2 Senior Member

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    I have taken MFDs from other cars which have more plugs on the back and can take other options but the main plug that runs all the MFDs I believe is the same from 04 to '09 The extra plugs that go on back of certain models like for the backup camera If you don't have a backup camera and you're putting a backup camera MFD into a base car it will plug right in and work when you go into reverse it doesn't do anything except back up there's no picture no screen is lit up none of that You can see your heat and stuff while you're backing up in a base model car on the MFD but the plug that you need to have inserted on the back of the MFD is the same across the lineup even for the seven button MFD with GPS and all that I believe you can take a four button MFD from above a base shove it in a car that had seven button GPS and still have your basic four button MFD functions work The blue plug for the GPS antenna the backup camera stuff and whatever else off the seven button will be left hanging obviously.