Bosch Relays all look the same. | FerrariChat

Bosch Relays all look the same.

Discussion in 'Technical Q&A' started by JohnnyS, Sep 11, 2008.

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  1. JohnnyS

    JohnnyS F1 World Champ
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    Having looked at the Bosch style relays found in 328s, they look the same but the different models seem to have different operating amp design. So, I think a 40 amp relay would be fine where an old 20 or 30 amp relay was origional.

    Am I correct on this?
     
  2. ferraridriver

    ferraridriver F1 Rookie

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  3. FandLcars

    FandLcars F1 Rookie

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    I think there are a few threads somewhere discussing replacement relays. Try a search... :)
     
  4. PAP 348

    PAP 348 Ten Time F1 World Champ
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    You are better off replacing the relays with the correct amperage relay that belongs there mate. ;);)

    Its just like fuses. You should never replace a fuse with a bigger one, that only leads to trouble down the track. :):)
     
  5. JohnnyS

    JohnnyS F1 World Champ
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    Did that first and didn't find the info I was seeking. Key words are so important!
     
  6. FandLcars

    FandLcars F1 Rookie

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    I certainly agree with Pap on this (as on most everything :D) Check the rating of the relays and make sure new ones are rated the same. You also might try posting in the 308/328/Mondial area if you haven't already.

    Here's a good thread about 328 relays from a couple months ago. It also mentions that Tyco Electronics purchased the Bosch relay business some time ago. So you might try searching also for Tyco relays, or something like that. You're right that keywords are very important ;)

    http://www.ferrarichat.com/forum/showthread.php?t=203396&highlight=328+relays
     
  7. miketuason

    miketuason F1 World Champ
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    #7 miketuason, Sep 11, 2008
    Last edited by a moderator: Sep 7, 2017
    There are few diff types of relay, this are just a few that I can remember on top of my head;
    1)normally open
    2)normally close
    3)double contact
    4)double throw
    Image Unavailable, Please Login
     
  8. JohnnyS

    JohnnyS F1 World Champ
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    #8 JohnnyS, Sep 11, 2008
    Last edited: Sep 11, 2008
    Yep, I think that if the type is same ( example Type A) the difference between a 20 amp and 40 amp is that the 40 amp is a like a "heavy duty" 20 amp switch that can handle the higher amp loading. Thus, as long as the type is correct, one can replace a 20 amp switch with a 30 amp or 40 amp switch.

    Unlike a fuse the relay is simply a switch and not meant to protect wiring.

    Am I wrong?
     
  9. GatorFL

    GatorFL Moderator
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    The proper relays are available from Ricambi, I think I did my 328 for less than $300 a few months back.
     
  10. WaltP

    WaltP Formula 3

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    I have to agree with you JohnnyS, the fuse protects the device being operated aand the wire to some extent, the relay is just a switch. Saying that I'd still go with what the factory put in but if needed I'd use a higher rated relay if I needed to but never a lower rated one.


     
  11. JohnnyS

    JohnnyS F1 World Champ
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    Thanks to everyone who posted to help out.

    Playing with the relays tonight I have found that both, yes both of them have failed in the "on" position. This is just too weird and I probably should have bought lotto tickets as some sort of weird luck has passed my way.

    Cheers!
     
  12. JohnnyS

    JohnnyS F1 World Champ
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    Nope, spoke too soon. Put the fuse panel back and the fans came back on. Pull panel out, fans are off. I think I have a short in the sensor wire going to the thermostat.
     
  13. JohnnyS

    JohnnyS F1 World Champ
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    Update for those that are interested:


    Poking around today and found the issue located on the right side of the fuse panel and with the middle vertical wire bundle connector. There are several "pink" wires that when moved, make/break contact and that makes the fans go on and off. No burn marks on the connector and no "bare" wires. I am not sure how I am going to "fix" this one.
     
  14. JohnnyS

    JohnnyS F1 World Champ
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    #14 JohnnyS, Sep 13, 2008
    Last edited by a moderator: Sep 7, 2017
    Nothing but rain today so decided to do some more on my 328.

    Here is a photo of the inside of a Bosch relay. Note that it is operated with a little electromagnet to close the switch. Contacts look good.
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  15. miketuason

    miketuason F1 World Champ
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    That's the Normally Open relay
     
  16. PAP 348

    PAP 348 Ten Time F1 World Champ
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    Sounds like there is a broken wire in there somewhere John. :):)

    If you can isolate which wire it is (I know it can be hard when they are closely bunched together ;);)), then hopefully you can cut out the damage section and solder in a new piece of wire. If its too hard to do, perhaps take it to a good auto-elec and let them sort it out. :p:p
     

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