Speedo (odometer) failure | FerrariChat

Speedo (odometer) failure

Discussion in '308/328' started by johnvwatts, Apr 5, 2010.

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  1. johnvwatts

    johnvwatts Formula Junior

    Jul 7, 2007
    522
    England
    Full Name:
    John v watts
    #1 johnvwatts, Apr 5, 2010
    Done a search and found that the failure of the odometer in the speedo in 308's seems pretty common. The problem seems to be a failed capacitor (?) or whatever but these seem to be hard to get hold of. Is anyone now selling a permanent solution to this ie a new remanufactured board that could just fit straight into the old unit. Or the capacitors?

    I am in England and there don't seem to be any speedo firms fixing these . Otherwise it is post it to North Hollywood Speedos.
     
  2. Paul_308

    Paul_308 Formula 3

    Mar 12, 2004
    2,345
    #2 Paul_308, Apr 5, 2010
    I've never heard of a capacitor involved with the speedometer. But the speed sensor which is located on the engine at the gearbox atop or below the oil pump (depending on year), may require replacing. They go bad more than speedometers because of their harsh environment. And of course, poor contacts are always suspected in any electrical system.

    Can you list your car year etc in your profile?
     
  3. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    17,940
    USA
    #3 f355spider, Apr 5, 2010
    John,
    As Paul stated, the sender is the more common failure point. If you are sure the sender is working and the speedo is at fault, then yes, send it in for repair.
     
  4. johnvwatts

    johnvwatts Formula Junior

    Jul 7, 2007
    522
    England
    Full Name:
    John v watts
    #4 johnvwatts, Apr 6, 2010
    Last edited: Apr 6, 2010
    No its the speedo unfortunately. The speed is working ie the needle but the odometer does not. Normally I agree the sender does go bad but they are easy to change and available . The internals of the speedo are much more difficult to fix as its one of the chips (not capacitor - sorry) that go wrong and they are not easily available but I've had a very helpful pm from the USA if I can't get it fixed in England.

    Its on a 78 GT4.
     
  5. greyboxer

    greyboxer F1 World Champ

    Dec 8, 2004
    12,314
    South East
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    Jimmie
    #5 greyboxer, Apr 6, 2010
    Talk to Speedy Cables in South Wales
     
  6. johnvwatts

    johnvwatts Formula Junior

    Jul 7, 2007
    522
    England
    Full Name:
    John v watts
    #6 johnvwatts, Apr 6, 2010
    will do thanks.
     
  7. wakko

    wakko Rookie

    Jul 18, 2006
    35
    Chicago IL
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    Eric Becker
    #7 wakko, Apr 12, 2010
    what if the speedo comes and goes and the odometer never moves?
     
  8. Paul_308

    Paul_308 Formula 3

    Mar 12, 2004
    2,345
    #8 Paul_308, Apr 13, 2010
    Vintage Ferrari speedometer assemblies have IC circuitry which converts electrical pulses from the engine to electrical pulses to the odometer and also produces an analog voltage to the electrical meter called the speedometer. If one or the other output devices fail, that driver circuitry must be repaired by a shop with the proper equipment.

    I.e...it's not owner serviceable. There are those who have tried back engineering the assembly...I've seen references in other Euro car forums, but never in FChat. In the US we commonly use PaloAlto Speedometer shop as they are reasonable and do a quality job. If you find 'Speedy Cables' to be competent (their website is impressive), you might report back that information.
    http://www.speedycables.com/repair.html


    _______________________
    http://www.FerrariWiring.com
     
  9. BwanaJoe

    BwanaJoe Formula 3

    Oct 23, 2006
    1,764
    Former Space Coast
    Full Name:
    Joe Burlein
    #9 BwanaJoe, Apr 13, 2010
    Per a previous thread (mine) there are no IC chips left anywhere that anyone knows about. If you find someone who has them and is fixing the speedos please let us know!
     
  10. johnvwatts

    johnvwatts Formula Junior

    Jul 7, 2007
    522
    England
    Full Name:
    John v watts
    #10 johnvwatts, Apr 13, 2010
    Haven't posted it off yet but have spoken to them and they reckon 'no problem done loads' but I will let you know.
     
  11. gerritv

    gerritv Formula 3

    Jun 18, 2001
    1,400
    St Catharines
    Full Name:
    Gerrit
    #11 gerritv, Apr 14, 2010
    Hi Paul
    It depends on the owner :) There are a few threads here where myself and RJay reverse engineered the PCB. Sometimes it is not the chip, it is the transistor on the final odometer drive circuit (although it is usually the chip). While Veglia isn't the only company who used the SAY115Y, we never found a reference to another car that used the same chip. I have recently woken up my 'replace the whole board' project, I will be providing an update on that in about a month.
    Sooner or later there will be no chips left, probably sooner. The one source we had located ran out of their stock of 68 early last year.

    Gerrit

     
  12. 308geo

    308geo F1 Rookie

    Nov 13, 2002
    2,751
    Houston, TX
    Full Name:
    George Benton LaFleur
    #12 308geo, Apr 15, 2010
    Look up Hollywood Speedometer in (where else) Hollywood, Ca. They re-did mine (including a re-facing & recalibration for about $125.
     

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