Dead when key is on | FerrariChat

Dead when key is on

Discussion in '308/328' started by Tony K, Aug 5, 2008.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. Tony K

    Tony K Formula 3

    Jun 7, 2006
    1,771
    Toledo, Ohio
    Full Name:
    Tony K.
    #1 Tony K, Aug 5, 2008
    Last edited: Aug 5, 2008
    Hello all,

    I'm hoping to save an hour or so with the multimeter in the hopes that maybe this is a common problem. I have NOT checked it out yet -- hoping maybe someone can tell me where to look first:

    Car is a 1980 308 GTBi. It has Birdman's fuse blocks. When it was about 70 miles into a 100 mile freeway trip, everything electrical died, and the car shut off. Cursory inspection revealed the following:

    - Fuel pump fuse blown
    - Everything associated with the ignition key is dead. In other words, everything that is supposed to turn on or happen when the ignition key turns on is not happening. i.e., Headlights/tail lights work, as they can be any time. Dome light works, as it can be any time. Hazards work when key is off, but not when key is on (I believe they operate on a different circuit with the key on because of the turn signals). Radio, starter, wipers, power windows, etc. etc. etc. don't work; nothing that works with the key comes alive. Basically, it is like there is no connection at the ignition key. Dead at the start position, too.
    - Replaced fuel pump fuse, everything is still dead.
    - Battery drained from full to dead in about 8 days with car parked in garage waiting for me to look at it, nothing left on. (I've been away on a business trip.)


    So, the obvious thing for me to check is if there is a burned contact on the ignition switch. . . . But I thought I would ask the experienced folk here for other possibilities, such as:

    - is there a main circuit (like the #1 fuse that excites all of the relays) that can kill all of the function of the "on" and "start" position of the ignition switch? i.e. where do those wires from the ignition switch go, before I go blind looking at the diagram in the owner's manual . . .

    - does a blown fuel pump fuse or break in that circuit kill everything, or just the fuel pump?

    - are the ignition switches known to burn contacts?

    - any specific circuits or places to check?


    I appreciate all of your input. :)


    Thanks,

    Tony K.
     
  2. GatorFL

    GatorFL Moderator
    Moderator Owner

    Nov 18, 2005
    16,376
    Wellington, FL
    Full Name:
    Duane
    Had a similar problem with my '86 328. The "All keys" relay went bad. Not sure if the early 308's had similar relay setup but if so you might want to check it.
     
  3. smg2

    smg2 F1 World Champ
    Sponsor

    Apr 1, 2004
    15,511
    Dumpster Fire #31
    Full Name:
    SMG
    the key 12v+ switch power relay is most likely bad, the run/on position powers the relay and the circuits from it along with the fuel pump relay and coils which feed the FI sensors too. to access the relays you'll need to drop the fuse panel as they are at the top on the left side.
     
  4. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,123
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    You guys are thinking "too modern" on this one -- there's no "key services" relay on a 308-2Vi.

    The +12V food chain is battery -to- 4-way connector -to- ignition key switch, and another food chain is battery -to- 4-way connector -to- fuel pump fuse #3. Measure the voltage on the large red wire connected to the top of fuel pump fuse #3 relative to ground -- should always be +12V (even with the key "off"). If it's not +12V, you need to check for +12V power at the 4-way connector (sometime called the AMP terminal board) which is behind the relay panel IIRC.
     

Share This Page