WHAT TERMINAL ON THE MAP SENSOR PLUG IS GROUND?

  • Tiny
  • Eddietomas
  • 1995 MITSUBISHI MIRAGE
  • 120,000 MILES

My check engine light came on throwing a code 105 which is map/barometric pressure circuit malfunction. I ran through the tests but I cant figure it out because I dont know what the terminals are. The thing that puzzles me is all of the terminals have some kind of voltage its a 3 bar connector, the first wire (green) has 5.3v second (black) has.04v and third (white with red stripe) has.04v I checked for resistance in the plug and it shows none. I dont know where to look from there? I also changed the map sensor and reset the ECU but it threw the code again after driveing a few miles. Thank you I appreciate your help.

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Wednesday, August 29th, 2012 AT 1:20 AM

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  • Tiny
  • Wrenchtech
  • EXPERT
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http://i1198.photobucket.com/albums/aa448/Wrenchtech/118945725.gif

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Wednesday, August 29th, 2012 AT 1:41 AM
  • Tiny
  • Eddietomas
  • MEMBER

Thank you sorry im not to good at reading the diagrams are 2&3 both grounded?

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Wednesday, August 29th, 2012 AT 2:04 AM
  • Tiny
  • Wrenchtech
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None of them are externally grounded. They all go through the PCM but the PCM supplies ground to #3 to read the signal return of #2. #1 is a 5v reference.

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Wednesday, August 29th, 2012 AT 2:07 AM
  • Tiny
  • Eddietomas
  • MEMBER

Ok does that meen my readings look alright? Thank you again for your help

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Wednesday, August 29th, 2012 AT 2:25 AM
  • Tiny
  • KHLow2008
  • EXPERT
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Terminal # 3 is the ground wire through the PCM but it is also linked to the other sensors such as TPS, IAT, ECT.

There must be continuity between the black wire and body ground.

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Wednesday, August 29th, 2012 AT 11:02 AM
  • Tiny
  • Wrenchtech
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As stated earlier, that ground is controlled by the PCM so the PCM has to be powered for testing it.

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Wednesday, August 29th, 2012 AT 11:06 AM

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