Fog light problem | FerrariChat

Fog light problem

Discussion in 'Mondial' started by Alden, Oct 23, 2015.

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

  1. Alden

    Alden F1 Rookie
    Rossa Subscribed

    Apr 25, 2010
    2,903
    Central Florida
    My fog lights only work when I pull the headlight stalk with the low beams on or off.

    When I push the fog light switch, the indicator lights up on the panel, but the lights do not come on.

    Fuse and relays are brand new and I even tried swapping the old relay back in just in case.

    I assume they are supposed to come on when the switch is pressed and go off when the high beams are turned on, right?

    Any advice on where to start looking?
    Alden
     
  2. theunissenguido

    theunissenguido Formula 3
    Owner Silver Subscribed

    Jan 21, 2004
    2,371
    Argent/Brasil
    Full Name:
    Guido
    What lights do you mean ?
    For the rear fog lights, its usual in Europe that they only work with low beam on.

    Guido
     
  3. MvT

    MvT F1 Rookie

    May 25, 2013
    4,248
    The Netherlands - NH
    Full Name:
    Tijn
    3.2 and T that are U.S. do not have fog lights, on the rear that is. Front are actually flashing lights, which is your current setting. The front fog light button works only if you rewire it to the fog light wires that are hanging lose on the front flashing light cable (Disconnected). They have white round casings around it. These lose hanging wires are usually cut away by previous owners.
     
  4. FamilyCar

    FamilyCar Formula Junior
    Rossa Subscribed

    Sep 26, 2007
    655
    Seattle, Wa
    Full Name:
    Peter Goodall
    My US spec car does have fog lights, although they only work when the parking lights or low beams are on. Try making sure those are on. They will go off if the high beams are engaged. They also do flash when the stalk is pulled back.

    If they still don't work it is probably a relay issue, since it has a rather complicated means of actuation.
     
  5. FamilyCar

    FamilyCar Formula Junior
    Rossa Subscribed

    Sep 26, 2007
    655
    Seattle, Wa
    Full Name:
    Peter Goodall
    Oops, didn't read carefully. Sounds like you're on the right path.

    Do your instrument and side marker lights work correctly?
     
  6. FamilyCar

    FamilyCar Formula Junior
    Rossa Subscribed

    Sep 26, 2007
    655
    Seattle, Wa
    Full Name:
    Peter Goodall
    Looking at a wiring diagram here. Since you have power at the switch, the wire path between there and the fog lights is likely the problem as it is pretty simple. It should go back into the fuse panel from the switch in position 8, connector K, then back out of Connector V in position 3. It then splits to the two wires. It appears each light is grounded at or near the light, no wire path back.

    Prior to getting to the switch, the power comes from position 3 on connector J, which is where my car cooked it, taking down the marker and instrument lights as well. I don't think the indicator switch would work if the problem where there, but I don't have time to look into it now since it's on a different diagram.

    I can send a pdf of the diagram with color traces over the wires I researched if that helps. PM me.

    This all comes from Table 10 in the wiring diagram.
     
  7. Alden

    Alden F1 Rookie
    Rossa Subscribed

    Apr 25, 2010
    2,903
    Central Florida
    Thanks for the replies, I would appreciate the PDF of the wiring diagram, thanks!

    Yes, the fog lights only work when you flash them with the stalk. They will not come on by themselves or with the low beam headlights.

    No rear fogs on most US cars, though I have them on my Jag, they are great when someone is tailgating you. On the Jag they are like super bright brake lights. Give them a fog light flash instead of tapping the brakes and accelerate away!

    Alden
     
  8. Alden

    Alden F1 Rookie
    Rossa Subscribed

    Apr 25, 2010
    2,903
    Central Florida
    Can you give me some more info about the location of the wiring you are talking about?

    Why would a PO cut the wires?
    Alden
     
  9. Alden

    Alden F1 Rookie
    Rossa Subscribed

    Apr 25, 2010
    2,903
    Central Florida
    Yes, all is OK except the fog lights.
    Alden
     
  10. MvT

    MvT F1 Rookie

    May 25, 2013
    4,248
    The Netherlands - NH
    Full Name:
    Tijn
    I'll make some pics tomorrow. It's now pitch dark here :)
    POs would perhaps not like lose hanging wires and often you'll see them hanging through the front grill. Not ideal for car shows I guess.
     
  11. Wade

    Wade Three Time F1 World Champ
    Owner

    Mar 31, 2006
    32,793
    East Central, FL
    Full Name:
    Wade O.
  12. FamilyCar

    FamilyCar Formula Junior
    Rossa Subscribed

    Sep 26, 2007
    655
    Seattle, Wa
    Full Name:
    Peter Goodall
    Send me an email address if you want the file. It is a 2-page pdf but is too large to upload here. It is figures 6 and 10 from the wiring diagram combined onto a single page (each) with the numbered key attached and some annotations.
     
  13. moysiuan

    moysiuan F1 Rookie
    Silver Subscribed

    Nov 1, 2005
    3,628
    Canada
    My Swiss car functions like yours, and is in accordance with how the owners manual says it is supposed to work for a Euro spec car.
     
  14. Alden

    Alden F1 Rookie
    Rossa Subscribed

    Apr 25, 2010
    2,903
    Central Florida
    PM sent, thanks!
    Alden
     
  15. dfranzen

    dfranzen Formula 3
    Owner

    Aug 31, 2013
    1,577
    Ponte Vedra Beach , FL
    Full Name:
    Don Franzen
    check the dash switch probably needs cleaning

    does the dash instrument fog indicator light come on when you push the button? if not most likely the button switch needs cleaning
     
  16. Alden

    Alden F1 Rookie
    Rossa Subscribed

    Apr 25, 2010
    2,903
    Central Florida
    Yes, the dash light comes on when the fog light switch is pushed.

    I will clean the switch anyway.

    Thanks
    Alden
     
  17. MvT

    MvT F1 Rookie

    May 25, 2013
    4,248
    The Netherlands - NH
    Full Name:
    Tijn
    #17 MvT, Oct 24, 2015
    Last edited by a moderator: Sep 7, 2017
  18. Alden

    Alden F1 Rookie
    Rossa Subscribed

    Apr 25, 2010
    2,903
    Central Florida
    Behind the fog lights?

    And if I connect them then the lights will come on when I push the switch on the dash?
    Alden
     
  19. MvT

    MvT F1 Rookie

    May 25, 2013
    4,248
    The Netherlands - NH
    Full Name:
    Tijn
    Yep that's correct. You can use a test listed and use the chassis as ground, then you will see that the test light goes on when the fog button pushed.
     
  20. BillyD

    BillyD Formula 3
    Silver Subscribed

    Feb 28, 2004
    1,774
    Pacific Northwest
    Full Name:
    Bill
    Anyone have a fog light/light flasher circuit that is readable. No matter how much I try it’s impossible to follow the wires to diagnose my no light problem.
    Thanks
    Bill
     
  21. theunissenguido

    theunissenguido Formula 3
    Owner Silver Subscribed

    Jan 21, 2004
    2,371
    Argent/Brasil
    Full Name:
    Guido
    #21 theunissenguido, Feb 2, 2019
    Last edited: Feb 2, 2019
    Bill what is the problem ? Are both fog light out of service or just 1 ? 90% fault at connection to chassis, so try connection to chassis first with an other wire.
    Included QV schematics...if opens anyway.
    Page 10, number 4 Auxiliary fog lights ?
    Connections = Black to chassis, SN color wire to upper connector white plug U (middle of vertical on left side FB)
    and also to 3e lower connector white plug V (right of vertical on left side FB). This goes internal to white plug K (5e from left) then to switch 37.
    White plug U (1e upper) goes internal FB to Relais R (87a middle connector) over 30 upper connector relais R, to White plug X (nr 11 counting from left)....than to switch 80 (lights on steering) wire color AN. From there it goes over Hazard light switch 59 ....did I tell how complicated this electric sistem is ?

    Guido
     

    Attached Files:

  22. BillyD

    BillyD Formula 3
    Silver Subscribed

    Feb 28, 2004
    1,774
    Pacific Northwest
    Full Name:
    Bill
    Thanks! That schematic is much better.
    I have no fog lights either via stalk pull or fog light switch on dash. The light on the dash lights up when I use the switch but no fog lights. I don’t hear or feel a relay energize when either stalk or switch is energized.
    And yes from the little I was able to see on my schematic it’s a crazy circuit. No wonder we have electrical problems.
     
  23. mike32

    mike32 F1 Veteran

    May 13, 2016
    5,828
    Isle of man- uk
    I can e mail you the complete wiring diagrams book for the car if you need it
     
  24. theunissenguido

    theunissenguido Formula 3
    Owner Silver Subscribed

    Jan 21, 2004
    2,371
    Argent/Brasil
    Full Name:
    Guido
    Are you shure the bulbs are ok ?!
    Guido
     
  25. BillyD

    BillyD Formula 3
    Silver Subscribed

    Feb 28, 2004
    1,774
    Pacific Northwest
    Full Name:
    Bill
    Thank you again, you were right on both accounts. Both lights have bad grounds, and one light has bad wire from fuse box to light. At least I have one working now. (0) (-)
    Sure makes it easy to just troubleshoot between FB and light.
    Thanks again you saved me hours of looking at diagrams and disassembling who knows what.
     

Share This Page