86 testarossa | FerrariChat

86 testarossa

Discussion in 'Technical Q&A' started by jerry v, Jul 21, 2019.

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

  1. jerry v

    jerry v Rookie

    Nov 15, 2010
    16
    Cant find brake light switch. Please help. 86 testarossa
     
  2. ago car nut

    ago car nut F1 Veteran
    Silver Subscribed

    Aug 29, 2008
    5,246
    Madison Ohio
    Full Name:
    David A.
    Lift carpet under front trunk. Next to master cylinder.
     
  3. jerry v

    jerry v Rookie

    Nov 15, 2010
    16
    Thank you so much.
     
  4. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,040
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    If your brake lights aren't working, the trouble can also be a bad connection in the w or y white connector on the fuse-relay panel (the brake light current is surprisingly high -- like 8~10 A -- and can frazzle the terminals). Here are some photos showing the location David mentioned and diagnostic information that you may find helpful:
    Image Unavailable, Please Login

    Image Unavailable, Please Login

    A good reliability improvement IMO is to add a jumper wire to directly connect the red wire in the w connector to the red wire in the y connector.
     
  5. xplodee

    xplodee Formula 3

    Jan 3, 2017
    1,101
    Allentown, PA
    Full Name:
    Tim
    What about an LED brake light with lower current draw?
     
  6. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,040
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    Sure, using LEDs instead of incandescents would help a lot, but it doesn't stop someone from putting incandescent bulbs back in. Adding the jumper increases the reliability of the chassis regardless of the bulb type (that brake light signal needlessly just passes thru the fuse-relay PCB -- it isn't connected to anything else at all).
     
  7. ago car nut

    ago car nut F1 Veteran
    Silver Subscribed

    Aug 29, 2008
    5,246
    Madison Ohio
    Full Name:
    David A.
    Steve, what about a separate relay near the M/C from the (blue/black) wire 12VDC. to red wire to brake lights. I burned thru 2 brake like switches.
     
  8. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,040
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    Yes, using the red wire in the w connector (from the brake light switch) to close a relay connecting the blue-black wire to the red wire in the y connector would greatly reduce the current in the brake light switch (but I'm not a fan of adding complexity). Have you ever measured the actual current in your brake light circuit? I'm at 84K miles, and still on my original brake light switch so you seem to be cursed ;) Maybe someone has done something like replaced the brake light bulbs in the chiclet with some much higher wattage bulbs and this is over stressing your brake light switch contacts or made some other bizarro modification. Another possibility might be your LH rear bonnet gas spring body (which conveys the brake light signal up to the bulbs on the chiclet) might be occasionally shorting to the engine bonnet, and if this coincides with the brake lights being "on" could give a big current spike (look for a wear scar on the gas spring body). Just some random thoughts...
     
  9. ago car nut

    ago car nut F1 Veteran
    Silver Subscribed

    Aug 29, 2008
    5,246
    Madison Ohio
    Full Name:
    David A.
    Thanks Steve!
     
  10. jerry v

    jerry v Rookie

    Nov 15, 2010
    16
    Thank you guys. It was bad contacts in the brake switch. Took it apart cleaned them works perfect.
     

Share This Page