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308 QV passenger side mirror diagnosis

Discussion in 'Technical Q&A' started by cecinestpasunjan, Jun 25, 2006.

  1. cecinestpasunjan

    Sep 15, 2004
    51
    Frankfurt, Germany
    Full Name:
    Jan
    #1 cecinestpasunjan, Jun 25, 2006
    Last edited by a moderator: Sep 7, 2017
    Having fixed the electric window today, I had a look at the mirror as well which doesn't move (see picture below).

    1) Does anybody know, how to remove the glas in this type of mirror ?

    2) I investigated the current to the four cables of the PASSENGER SIDE MIRROR in all different switch positions with a control lamp connected to the ground. Here are the results in a spreadsheet:

    There is always a current on the brown cable.
    Connecting the white cable via the control lamp with the ground always produces a weak light and a click sound on BOTH mirrors.



    Selected mirror: passenger side mirror

    cable blue cable black cable
    ----------------------------------------------------------------
    "multi-direction switch" :
    up off on
    down on off
    forward on off
    back off on



    Selected mirror: driver side mirror

    cable blue cable black cable
    ----------------------------------------------------------------
    "multi-direction switch" :
    up off on
    down off off
    forward off off
    back off on


    Is this the response you would expect? How can I check if the mirror motor is still working?
    What I don't understand is why I get a current on the black cable of the passenger side mirror in the up and forward position when in fact the driver side mirror is selected. Furthermore, what's the role of the white cable?

    Any comments are appreciated!
    Jan
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  2. wolftalk

    wolftalk Formula Junior

    Jan 27, 2004
    367
    san franciso area
    Full Name:
    phil
    disclaimer - this is talking about a USA 328 mirror, but it's probably the same as the 308/euro mirrors.

    1] the mirror glass is stuck to a plastic backplate that is mounted to the pivoting motor assembly. Press an edge of the glass inward to pop the opposite edge out as far as possible. You'll hear a ratcheting sound as some gearing jumps teeth. That's ok...it has to do that.

    An edge of the mirror is now exposed enough to force a feeler gauge (or something else as thin as possible) between the glass and the plastic backplate. I think they used double-sided tape to stick the two pieces together, so you are slicing into it/scraping it off the backplate. Once you get started, squirting an adhesive solvent like goof-off/goo gone between the pieces may help, but I separated them just by "sawing" my way around the mirror perimeter with the feeler gauge and a thin putty knife.

    2] There are 4 wires going to the mirror assembly. Inside the thing is a motor and a solenoid. The motor spins both directions depending on the polarity of the 12V/gnd applied to it, and the solenoid changes which axis the backplate is pivoting around.

    On the 328 mirror, the black and blue wires are the motor winding, and you should measure something around 45 ohms across those two wires. The white and brown wires are the solenoid, and should be around 60 ohms.

    To test the motor, unplug the connector and measure the resistances. You can also jumper power to the wires.

    For example, putting 12V on the black wire and grounding the blue wire will make the mirror pivot one way around the vertical axis. Swap the 12V/gnd and it pivots the other way aound the vertical axis.

    Put 12V/gnd on the white and brown wires and you'll hear the solenoid click.

    To pivot the motor around the horizontal axis, you have to power the motor and solenoid at the same time. e.g. connect white and blue to 12V, brown and black to gnd.

    In the car, either the brown or white wire is tied to ground - depends which mirror. The non-grounded white or brown wire is switching 12V on/off to the solenoid.

    Most of the wiring from the switch goes to both the mirrors. Ferrari just plays games with how those wires connect to each mirror so circuits are only completed to one mirror at a time. That's why the wire colors don't match between the chassis wiring harness and the wires on the mirror at the mirror plug.

    btw, when reinstalling the mirror glass, make sure to use something strong enough. I used a silicone adhesive instead of double-sided tape, which works fine. You just want something that you can cut/scrape/peel off again if needed. Make sure whatever you use sticks well, otherwise at high enough speeds the air suction will pull the glass off (I'll invoke the 5th amendment on how high a speed :)).

    The mirror glass itself is blue-tinted vitaloni glass. I never could find a source for it in the US, so had to have a glass shop cut me a replacement from normal mirror stock until I got hold of a scrap mirror and stole the glass off it. Oddly, the blue-tinted glass may be illegal in some/all of the US these days, which made finding even the aftermarket vitaloni mirrors difficult at the time. The glass in them was too small anyway for the US mirror, but is plenty big enough to cut down to the euro sized one.

    On an even more unrelated side note, using a test light can create some confusion. Recommend buying a cheap multimeter. The test lights can put loads on the circuits and cause them to function differently. The meters won't do that....and you'll be able to measure voltage and resistance values directly.
     
  3. cecinestpasunjan

    Sep 15, 2004
    51
    Frankfurt, Germany
    Full Name:
    Jan
    Thanks very much Phil for your comprehensive reply - very helpful!

    I just saw that my spreadsheet got totally screwed up during the posting process. Unfortunately the resulting mess is not really understandable.
    From what you said I conclude that the solenoids are okay and I got an idea how to check the motor.
    Nevertheless, what I still don't understand is why I get a current on the black cable of the PASSENGER SIDE mirror in the up and forward position of the "direction switch" having actually selected the DRIVER SIDE mirror. This should result in two mirrors moving at a time, right?
    Latest on the next weekend I will try to further nail down the problem. With all the available information my guess is that the motor is out of order.
    Let's see...

    Jan
     
  4. wolftalk

    wolftalk Formula Junior

    Jan 27, 2004
    367
    san franciso area
    Full Name:
    phil
    hi jan,

    they way you are checking is getting you messed up. Sounds like you are providing your own ground connection for the test light rather than tying to the wires that ferrari is using.

    I don't know how familiar you are with circuits, but just in case...you can think of the motor as a two terminal device. You must connect one terminal to 12V and the other to ground so current can flow through the motor.
    If you disconnect either terminal, current can't flow.

    depending on the position of the switch, 12V may be getting connected to both mirror motors, but the switch is only grounding one of them, so only that motor spins. It's just a side effect of the way the circuit is designed. It's done to minimize the number of wires you need.

    the 328 schematic shows that the black wire is the same wire running to both mirrors, so when the switch puts 12V on it, you'll get the 12V on both mirrors at the same time. The blue wire to each mirror, however, is individually controlled by the switch, so it can operate the motors independently.

    like the windows, which wire has 12V and which one has ground changes. The switch swaps them to reverse the direction the motor spins.

    It's very common for 12V to always be applied to one side of a device, and the circuits are mucking with the ground side. Finding 12V on one side doesn't mean that the device is powered - the ground side needs to be connected also for the current to flow.

    anyway, you need to connect your test light between the black and blue wires to check that the switch is working correctly, though I'd still strongly recommend you get a multimeter (often generically called voltmeters). They are available for under $10.

    although not relevant in this case, a test light can be dangerous with transistorized circuits because a lot of current can flow through it, so you wouldn't want to go poking around the engine or injection ECU circuits with one. A meter won't have that problem.
     
  5. cecinestpasunjan

    Sep 15, 2004
    51
    Frankfurt, Germany
    Full Name:
    Jan
    Phil,
    I used the lamp because my last multimeter only survived half a year or so but I got your point regarding the ground connection and will invest in a better instrument.
    Additional results hopefully by Sunday.

    Jan
     
  6. cecinestpasunjan

    Sep 15, 2004
    51
    Frankfurt, Germany
    Full Name:
    Jan
    Here are the results from my recent measurements:

    mirror cables blue vs. black --- 77 Ohms
    mirror cables brown vs. white --- 60 Ohms

    Secondly, I tried to run the motor by connecting the black mirror cable with (+) and the blue cable to the ground (and vice versa). Nothing happened in both cases apart from a little spark at the ground connection.

    Is this in your mind sufficient proof for a motor malfunction?

    Jan
     
  7. wolftalk

    wolftalk Formula Junior

    Jan 27, 2004
    367
    san franciso area
    Full Name:
    phil
    hi jan,

    when you did the measurements and jumpering power/gnd, you are doing it directly to the mirror, right? (unscrewed the mirror from the door and pulled apart the connector plug, then measured/jumpered directly to the plug).

    If you are measuring/jumpering anyplace else in the harness - like at a switch connector - then both window motors could be in the circuit and you may be shorting 12V to ground through one of the switches.

    measuring 77ohms on the motor is a little odd. Usually when a motor goes phut the winding either opens or melts into a blob, resulting in infinite or zero ohms.

    if you are poking around directly at the mirror connector and the motor is not working, then yeah, either the motor is seized, or the mechanism is jammed.
    Worth popping off the glass to take a look inside.

    The mirrors were probably made by vitaloni, and lots of other manufacturers used vitaloni also. The US spec 328 mirrors are much bigger, but the motor may be the same. If you do take off the glass, take a pic/measurements of the motor and I'll open up my spare and compare.
     
  8. cecinestpasunjan

    Sep 15, 2004
    51
    Frankfurt, Germany
    Full Name:
    Jan
    So far, I did the measurements at the wires outside the mirror housing. I simply disconnected the 4-way connector between the mirror cables and the rest of the harness and measured on the side of the mirror cables.

    Based on what you wrote I will try to remove the glass and hopefully dismount the motors (in order to measure them separately), initially without unscrewing the mirror from the door.

    Thanks for the crash course in Car electrics and for your patience!
     
  9. wolftalk

    wolftalk Formula Junior

    Jan 27, 2004
    367
    san franciso area
    Full Name:
    phil
    #9 wolftalk, Jul 1, 2006
    Last edited by a moderator: Sep 7, 2017
    hi jan,

    attached is a picture of the inside of a US spec mirror. There just one motor, which is the bigger can on the bottom. The smaller can on the top is the solenoid which changes the axis of rotation. The black surface is what the mirror is stuck to, and the white part is the gimbal (if that's the right word) which allows the black piece to pivot on two axis.

    if the mirror is still screwed onto the door, I'd take it off first before removing the mirror glass. The spare mirror I have has sliced up wiring between the connector and the mirror which you couldn't see with the mirror still mounted.
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  10. cecinestpasunjan

    Sep 15, 2004
    51
    Frankfurt, Germany
    Full Name:
    Jan
    #10 cecinestpasunjan, Jul 2, 2006
    Last edited by a moderator: Sep 7, 2017
    Hi Phil,

    Yesterday, I took the motor out (see pics).
    It looks like the one you posted.
    I repeated the resistance measurements on the actuator shown with the following results:
    br. / white : 68 Ohms
    black / blue: 150 Ohms

    Since I wasn't alble to further dismount the assembly in order to isolate the different motors I will try to purchase the complete actuator unless you have a different advice.
    I found out that it was made by
    Eaton IKU Montfoort BV
    Netherlands
    Since your US mirror contains the same device I am confident that it has been used broadly. Furthermore, the company still exists.

    Btw: Although I removed the glass with a solvent which I injected with a syringe it turned out that the actuator can easily be removed together with the glass in one piece by just removing two screws in the bottom of the mirror.

    Havagooday!
    Jan
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  11. wolftalk

    wolftalk Formula Junior

    Jan 27, 2004
    367
    san franciso area
    Full Name:
    phil
    hi jan,

    sorry about the disassembly. On the US spec mirror, you have to take out the glass to get to the internals.

    If you find a source for the actuator, please let us know. You also have the option of getting a salvage mirror in bad cosmetic condition that you can take the motor assembly out of and swap it into yours.

    I got my spare on ebay that way.

    phil
     

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