How Do I Check Protection Relay | FerrariChat
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How Do I Check Protection Relay

Discussion in '308/328' started by Lawrence Coppari, Sep 2, 2009.

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  1. Lawrence Coppari

    Lawrence Coppari Formula 3

    Apr 29, 2002
    2,192
    Kingsport, TN
    Full Name:
    Lawrence A. Coppari
    #1 Lawrence Coppari, Sep 2, 2009
    Last edited: Sep 2, 2009
    My 328 is not running properly. At first it was an intermittent thing. Now it runs poorly all the time and I have noticed that the frequency valve is not vibrating. The last time it ran well intermittently I noticed that when the valve vibrated, it ran fine. Now it does not vibrate ever and engine runs pooly all the time. So the valve or the control of it is the problem. I have cleaned all the contacts in the trunk area. The fused relay that controls the frequency valve is on my desk.

    I'd like to test the relay to determine if it indeed is the problem. How can I do this? BTW, the relay rattles when shaken.
     
  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,854
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #2 Steve Magnusson, Sep 2, 2009
    Last edited: Sep 2, 2009
    Post #9 in this thread describes how the 328 protection relay should work:

    http://ferrarichat.com/forum/showthread.php?t=229660

    i.e., terminal 30 should be at +12V (always); terminal 31 is ground; whenever the engine is cranking or running, terminal 15 should be at +12V, which (if terminal 31 is at ground) closes the relay switch contacts and connects terminal 30 to terminal 87 -- i.e., when the engine is running terminal 87 should be +12V.

    The "rattle" certainly isn't a good sign. I assume that the 10A fuse is not blown, but it still might be a good idea to confirm that your alternator is OK by measuring voltage between the battery terminals when the engine is running (even if now running poorly) and make sure that it isn't a crazy high value. Give a shout if you need something more.
     
  3. Lawrence Coppari

    Lawrence Coppari Formula 3

    Apr 29, 2002
    2,192
    Kingsport, TN
    Full Name:
    Lawrence A. Coppari
    #3 Lawrence Coppari, Sep 2, 2009
    Thanks Steve for the information. I rigged the relay up to a car battery according to your electrical description. It did very little. Terminal 30 occasionally connected to terminal 87 (digital ohm meter) with 12v across terminals 15(+) and 31(-) when I thunked on the case. Power is reaching the terminals at the plug in the car so that appears ok.

    I'll order a new relay. You've been a real help.
     

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