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348 Mystery - Case of the Chattering Relay

Discussion in '348/355' started by D-348, Mar 30, 2010.

  1. D-348

    D-348 Karting

    May 6, 2004
    179
    Full Name:
    Dave Cochran
    Hi All,

    I've pretty much exhausted research on this site and on the car so I'm forced to "phone a friend", as it were. Here's the scoop:

    I have a 1994 348 Spider, and neither my fog lights or turn signals work although I've had the car for years and they've always worked in the past. Everything else in the car appears to work normally. One clue that I've been focused on is that whenever the lights are on and I press the switch on the center console to activate the fog lights, I hear a high pitched chattering coming from the relay for the turn signals/fog lights (I think it covers both and it is the top, left relay in the fusebox in the passenger foot rest).

    This behavior at the relay leads me to believe that the two problems, turn signals and fog lights, are related. I pulled the fuse box yesterday and all connections look good. I've checked every fuse in the car 5 times. I've also replaced and exchanged relays to ensure the relay isn't the problem. When I began to get desperate, I replaced the flasher for the turn signals, but no bueno.

    At this point I'm humbly asking for any thoughts our suggestions on what might be going on. I don't have the schematics for the car, but something is interfering with the voltage going into the relay to make it chatter.

    Has anybody out there had a this problem or know what I should do next in my troubleshooting? I've read a lot in the other posts about similar problems, but they tend to be on slightly different models and are slightly different problems. In this case, they used to all work fine, but suddenly went away and were replaced with the chattering from the relay, which is much less helpful for both seeing in the fog and indicating the direction of a turn to other motorists. For clarification, I get absolutely nothing with the turn signals, and the chattering with the fog lights.

    Any help would be greatly appreciated because the weather is getting nice and I can't really drive the car without the signals working.

    Thanks!
     
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  3. hotrod406

    hotrod406 Formula Junior

    Sep 18, 2007
    540
    Grand rapids area,MI
    Full Name:
    Tim
    I had a chattering relay that turned out to be a bad ground wire to the coil. It wouldn't pass enough current for the coil to generate enough magnetism to hold the contact to the 87 terminal. Not sure if that will help but it is one cause of a chattering relay. Either the power to that coil or the ground is marginal/bad.
     
  4. Miltonian

    Miltonian F1 Veteran

    Dec 11, 2002
    5,964
    Milton, Wash.
    Full Name:
    Jeff B.
    This sounds like a challenge! Couple of questions:

    First, what happens when you turn on the hazard flashers? Do they flash at all, and do you get an illuminated bulb at each of the four corners, or are one or more of them dead?

    Second, can we assume that you know where the turn signal flasher is located (under the carpet at the left side of dash)? Just want to make sure, since it isn't in the fuse panel area.

    You could do a test jumping the fog light relay to see if that engages the lights, and would help to narrow down the problem.

    By any chance did your car come from Canada, where the car may have been modified to include daytime running lights, and perhaps some sloppy electrical work may have been done?
     
  5. D-348

    D-348 Karting

    May 6, 2004
    179
    Full Name:
    Dave Cochran
    Thanks for the quick replies! And you honor me, Miltonian, O solver of the toughest problems.

    OK - on to your questions:

    - Flashers are completely dead also (I tried the trick of running them to get the turn signals working, but didn't get very far when they wouldn't come on). I don't get chatter with either the turn signals or the flashers - just silence and darkness...

    - yes, the flasher I replaced is the one at the top of the carpeted area on the right side of the drivers foot well on the side of the center console. I replaced it with an equivalent one from a local auto parts store (a trick that came from another thread on this site) but it didn't change anything

    - Haven't yet tried jumping the relay, sounds like that's next. Do I have to worry about shorting anything else out if I do that?

    - The car is a US car and is remarkably clean from a wiring standpoint (except for the 'ol door jamb problem, etc.)

    I'm off to short the relay and will report back.

    Thanks!
     
  6. Miltonian

    Miltonian F1 Veteran

    Dec 11, 2002
    5,964
    Milton, Wash.
    Full Name:
    Jeff B.
    Dave, this sure sounds to me like your switch panel on the center console is unplugged! It's easy to check, just pull back that panel that has the hazard and fog light switches and the fuel/oil temp gauges, and make sure that the gang plug is properly attached.

    I'm confused by your description of the location of the turn signal flasher relay. As far as I know yours should be in the same position as mine, which is just in front of your LEFT knee as you sit in the drivers seat, right next to the handle for the back-up front trunk release. There are two relays, the one on the left is for the turn signals AND hazard flasher. It's just behind the top edge of the carpet. The one on the right is a chime, as I recall.

    We'll get 'er fixed.
     
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  8. D-348

    D-348 Karting

    May 6, 2004
    179
    Full Name:
    Dave Cochran
    Well, thanks everybody. Miltonian, you nailed it again. I feel pretty silly, but I pulled out the side panel of the center console on the passenger side to have a good look at the wiring, and I immediately noticed a pretty large connector unplugged. It belonged in the back of the panel with the switch for the fog lights, so when I plugged it in, my car all of a sudden went back to "all systems go"! Thank you very, very, very much!

    I believe what happened is that when the radio, which died of old age, was replaced, someone (and quite possibly me) bumped the connector and caused it to come undone. It hadn't occurred to me because I knew when I pushed the button for the fog lamps, the relay chattered so I assumed that the switch was connected to something to cause an effect in the cars electrical system. Evidently, that's not so, and turned out to be the problem.

    Thanks again for the help, and I'm glad it turned out to be something simple like that. It was a wonderful/terrible feeling to fix the problem because I realized how much I can fix on the car and how much more I have to learn - even after living with this amazing machine all these years.

    Problem solved - chalk up another one for FerrariChat and Miltonian. Thanks!

    P.S. Miltonian, you're right on the flasher - I was going from memory because it had been a while since I exchanged the flasher and it is by the LEFT knee of the driver at the top of the carpet. I'm learning quickly that at my age, going by memory may not be the best strategy!
     
  9. Miltonian

    Miltonian F1 Veteran

    Dec 11, 2002
    5,964
    Milton, Wash.
    Full Name:
    Jeff B.
    #7 Miltonian, Mar 31, 2010
    Last edited: Mar 31, 2010
    Thanks for the credit, all aboard for the ego trip! Another one solved without spending any money, I love to hear that. Your good explanation of the problem provided the solution.

    Edit: Now, are you going to get in there and fix that door jamb problem?
     
  10. FandLcars

    FandLcars F1 Rookie

    Aug 6, 2006
    3,043
    Tempe, Az
    Full Name:
    Rick Schumm
    +348!!
     
  11. D-348

    D-348 Karting

    May 6, 2004
    179
    Full Name:
    Dave Cochran
    Yes, the 'ol door jamb. I fixed that years ago because when I bought the car, the passenger window could not be operated from the switch on the driver's side. So I got in their and fixed that one by adding a little extra wire to the harness and futzed with the connector - it's been working great ever since (knock on wood).

    Other than bulbs, that's all my car's really needed in terms of electrical work. And then there is this old one where I put the front bumper back together:

    http://www.ferrarichat.com/forum/showthread.php?t=66576

    Other than that, these are great cars with a few quirks, but heck - that makes them more loveable! Speaking of which the next thing on deck is to clean up the melting black center console panels, but I think I'm just going to enjoy it this summer, then use that as a winter keep-in-touch kind of thing. :)

    Thanks again for the help!
     
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