355 Suspension Light | FerrariChat

355 Suspension Light

Discussion in '348/355' started by Mazzie1983, Dec 17, 2023.

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  1. Mazzie1983

    Mazzie1983 Rookie

    Nov 13, 2019
    33
    Full Name:
    Caleb Ross
    Looking for help tracking down an intermittent suspension light. Recently had both the rear dampers rebuilt and the left side is producing and intermittent suspension light. It strangely started going on and off when it feels like it.

    I pulled the actuator and firmly re seated it which made the light go out. When going over a series of rough bumps the light came back on. I parked it in my garage for a week, returned to the light on, drove it for 30 minutes and the light disappeared after pulling out of a parking lot.

    It seems unlikely to be the actuator, all the gears look intact on inspection and I went two years with no fault on a leaking damper. It only appeared intermittently on the new rebuilt damper. The rebuilt damper on the opposing side is not causing the light either. Any thoughts on where to start with this?
     
  2. fboutlaw

    fboutlaw Formula Junior

    Dec 3, 2014
    260
    Woodside, CA
    That light is tied to the actuators. They go through an initialization procedure when powered on. It involves full range of motion in both directions. If they fail that, light goes on.

    It can fail because the gears are worn, the motor is worn, or the suspension twist valve is too stiff.

    To check the actuator itself, pull the one in question off the shock. Start a video filming the unloaded gear. Turn key to accessory position. Stop Video. Compare to the rest.
    ().
    I'm currently uploading what a good one looks like. If your actuator fails this on its own or is very sluggish, you need an actuator rebuild.

    If it passes, your shock valve could be too stiff.

    I've noticed on mine that if it's below 40F I do sometimes have a fail on start. If I let the car warm up a minute then restart it will go away.
     
    Mike Morrissey likes this.
  3. Qavion

    Qavion F1 World Champ
    Silver Subscribed

    Feb 20, 2015
    14,283
    Sydney
    Full Name:
    Ian Riddell
    How do you know the left side is causing the suspension light? The system doesn't tell you which side/actuator is faulty unless you have a Ferrari SD tool.

    The actuators break all the time. The gears may be ok, but how about the other pieces in the actuator?

    Image Unavailable, Please Login

    Unless you have a known serviceable actuator to interchange with a suspect actuator on the car, you won't know which actuator (if at all) is faulty.
    Just take it to a dealer or independent with an SD tool. It could be anything, including a brake pressure sensor or an accelerometer issue.
     
    fboutlaw, 308 GTB and Mike Morrissey like this.
  4. Mike Morrissey

    Mike Morrissey Formula 3
    Silver Subscribed

    Nov 2, 2018
    1,143
    Denver, Colorado
    Full Name:
    Mike Morrissey
    If you find the problem is with the actuator, Captain Z rebuilds them with metal parts. Excellent Work and fast turnaround.

    https://www.captainzcnc.com/
     
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  5. ferraridriver

    ferraridriver F1 Rookie

    Aug 8, 2002
    4,152
    Bay Area Calif.
    Full Name:
    Dave
    Qavion and taz355 like this.
  6. taz355

    taz355 F1 Veteran
    Owner Silver Subscribed

    Feb 18, 2008
    6,016
    Indio Ca/ Alberta
    Full Name:
    Grant
    I had 2 like that
     
  7. zstyle

    zstyle Formula Junior

    Jun 28, 2007
    552
    Tempe
    Full Name:
    Jon
    Be careful removing and replacing the motors without a SD2 for they are positioned and calibrated to know where the end of travel is due to amperage spikes and hard stops.
     
  8. taz355

    taz355 F1 Veteran
    Owner Silver Subscribed

    Feb 18, 2008
    6,016
    Indio Ca/ Alberta
    Full Name:
    Grant
    The motors being replaced I am unsure of but the whole units can be removed and moved around as much as you like
     
    WATSON and Qavion like this.
  9. WATSON

    WATSON Two Time F1 World Champ
    Owner Rossa Subscribed

    Sep 9, 2010
    23,684
    WI
    The ecu turns each suspension unit across a full stop from one side to another.

    Consequently it does not matter where they initially start.

    I have pulled mine numerous times without any issue or need for an SD computer.
     

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