Tach can problems

Early A-Body Discussions

  1. DECIPHER

    DECIPHER Well-Known Member

    Messages:
    244
    Likes Received:
    28
    Joined:
    Jul 27, 2015
    Location:
    Denver
    Local Time:
    6:57 AM
    does anyone know why my tech can with new digital insides doesn't want to work when the can body is grounded / mounted to body on kick panel where it belongs?
     
  2. chryslerfat

    chryslerfat Well-Known Member

    Messages:
    12,970
    Likes Received:
    6276
    Joined:
    Aug 23, 2008
    Location:
    Monroe,Michigan
    Local Time:
    8:57 AM
    Not sure as I have not used mine yet but you say when it is mounted to ground it stops working?
     
  3. DECIPHER

    DECIPHER Well-Known Member

    Messages:
    244
    Likes Received:
    28
    Joined:
    Jul 27, 2015
    Location:
    Denver
    Local Time:
    6:57 AM
    Yep if I un screw it and sit it on the carpet it works if I ground it to the body it does but severely drops to nothing and doesn't show correct rpm on rev
     
  4. 440DART1970

    440DART1970 1970 Dart 446ci Swinger

    Messages:
    589
    Likes Received:
    153
    Joined:
    Nov 9, 2016
    Location:
    NJ
    Local Time:
    8:57 AM
    Is the car and dash grounded?
     
  5. DECIPHER

    DECIPHER Well-Known Member

    Messages:
    244
    Likes Received:
    28
    Joined:
    Jul 27, 2015
    Location:
    Denver
    Local Time:
    6:57 AM
    Yep don't have problems with anyrhing else on car
     
  6. 440DART1970

    440DART1970 1970 Dart 446ci Swinger

    Messages:
    589
    Likes Received:
    153
    Joined:
    Nov 9, 2016
    Location:
    NJ
    Local Time:
    8:57 AM
    Try to run a wire directly from the battery ground to it and see what happens
     
  7. TrailBeast

    TrailBeast AKA Mopars4us on Youtube

    Messages:
    21,356
    Likes Received:
    8898
    Joined:
    Mar 11, 2011
    Location:
    Arizona
    Local Time:
    5:57 AM
    Ask whoever did the new digital insides.
    Sounds like they got the polarity reversed, or the case is in contact with the power supply for the electronics.
     
  8. DECIPHER

    DECIPHER Well-Known Member

    Messages:
    244
    Likes Received:
    28
    Joined:
    Jul 27, 2015
    Location:
    Denver
    Local Time:
    6:57 AM
    I Installed the guts in the can. Purchased a Formula S Cluster from a fellow member last year. Purchased a can that was no good and got the insides to put in. I used the wiring listed on the electronics i will verify my wiring again but it was pretty straight forward on the pcb silkscreen. Grounded out the tach works just very low, as in idle shows about 100 rpm and 2-3k is about half at 1500 readout. noticed when i would bump it with my left foot it would work for a couple days so i pulled the can from the kickpanel. Then running not attached it seemed alot more correct. I am sure i still need to adjust / verify with a under hood tach but non grounded case was better.
     
  1. This site uses cookies to help personalize content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.