Electrical problem in the ignition area

Discussion in 'Electronics Q&A' started by HughJ, Jan 23, 2023.

  1. HughJ

    HughJ New Member

    5
    Dec 29, 2022
    Australia
    2004 Sea Ray 270 Sundeck
    6.2 MPI Bravo |||
    6.2 MPI Bravo |||
    Hi all, I am restoring my 2004 Sundeck 270, purchased as a part finished project. Most of the systems are now up and running after converting the electrics from the original EIU micro processor and peanut switch pad to amore simple and reliable fuse block andswitches from FP Marine (thanks to the ownerthat posted that supplier, great qualityreplacement kit)

    I am hoping that someone has come acrossanother electrical issue I have that is giving me grief, being no power to the ignition coil,hi pressure fuel pump and fuel shut offsolenoid and non of the instruments show any sign of powering up! All circuit breakers on the engine have power to both terminals andthere is power to the ECU but no spark out ofthe coil and no instrument activity!
    The alarm check function is working and thestarter motor cranks the engine.

    Could it be the relay adjacent to the ECU???

    Appreciate any help/info on this problem.

    Cheers Hugh
     
  2. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx 502 mag
    2005 Baja 242 islander 496
    502 mpi Bravo 1
    496 mag B1
    Main power relay? They're cheap enough
     
  3. HughJ

    HughJ New Member

    5
    Dec 29, 2022
    Australia
    2004 Sea Ray 270 Sundeck
    6.2 MPI Bravo |||
    6.2 MPI Bravo |||
    Thanks Scoflaw, could you please give a hint on where the “Main power relay” can be found?
     
  4. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx 502 mag
    2005 Baja 242 islander 496
    502 mpi Bravo 1
    496 mag B1
    Very close to the ecm on top of motor
     
  5. Lazy Daze

    Lazy Daze Well-Known Member TECHNICAL Contributor GOLD Sponsor

    Apr 21, 2009
    PA
    Various
    Various
    Follow the load side of the battery switch. Does it go right to the starter on your engine? If so, look for a square, tan fuse attached to the starter post. I "believe" if that is blown that it would still allow the engine to crank, but there wouldn't be power to gauges/most switches. Check for 12V on both sides of the fuse. In lieu of that starter fuse, look for a black, square breaker with a little arm that swings out - it would relatively close to your battery.
     
  6. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx 502 mag
    2005 Baja 242 islander 496
    502 mpi Bravo 1
    496 mag B1
    If there is power to the breakers and ecm it's not the 90 amp fuse on the starter.
     
  7. HughJ

    HughJ New Member

    5
    Dec 29, 2022
    Australia
    2004 Sea Ray 270 Sundeck
    6.2 MPI Bravo |||
    6.2 MPI Bravo |||
    Thanks Scoflaw,
    Think I may have found the problem, I traced the ignition power wire to the relay that sits along side the ECU, power in but nothing coming out, removed it and tested on the bench and found it faulty, have ordered a new one.
    Thanks for your help
     
    Nater Potater likes this.
  8. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx 502 mag
    2005 Baja 242 islander 496
    502 mpi Bravo 1
    496 mag B1
    Good job
     
  9. Lazy Daze

    Lazy Daze Well-Known Member TECHNICAL Contributor GOLD Sponsor

    Apr 21, 2009
    PA
    Various
    Various
    Good point - I read too fast.
     

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