205 Fan module
  • Register
  • Help
Results 1 to 5 of 5

Thread: 205 Fan module

  1. #1
    Member mbyok's Avatar
    Join Date
    Jul 2001
    Location
    Sydney, NSW, Australia
    Posts
    97

    Default 205 Fan module

    My blower fan has been behaving erratically: cutting in and out; blowing at a high speed and then unexpectedly dying down. The fan itself seems fine. I am expecting it may have something to do with the blower module.

    Advertisement


    I have pulled the module out and cannot see that there is anything I can actually do to it. Is there anything that can be done? Can you bypass it? Do you just replace them. Any idea what they cost?

    Thanks

    Maurice

  2. #2
    Fellow Frogger!
    Join Date
    Dec 2003
    Location
    Sydney, southern suburbs
    Posts
    184

    Default

    I'm not quite sure what the difference is between the fan and the blower? Anyway I replaced my blower / fan unit a few weeks ago as the squeak had finally got to me. It was about $330 (and worth every cent! - a squeak may not sound serious but try enjoying the drive with hour after hour of 'squeak, squeak, squeak').

    I've still got the old one so you could try it in yours and see if it makes a difference before buying one. If you're interested pm me a contact evening phone number.

    Also there was a recent thread on blower fan problems that may help 205 Heater fan - how to re-lube?
    unfrogged (for now)

  3. #3
    Fellow Frogger!
    Join Date
    Jun 2001
    Location
    Sydney NSW Australia
    Posts
    137

    Default

    There is a technical difference between a fan and blower ... blower is a later term used to describe the heater 'blower' (or fan) where for many years now, fan motors in cars have been fitted with tangential blowers (as distinct from axial fans). But it's just terminology really .. correct term would be heater blower.

    [Contrast with the radiator fan .. still an axial type].

    And you're probably right - the control module is the likely culprit .. here are two additional threads..

    1988 205 CTi Heating fan not working

    306 heater/air con fan

    Denis

  4. #4
    Member mbyok's Avatar
    Join Date
    Jul 2001
    Location
    Sydney, NSW, Australia
    Posts
    97

    Default

    Thanks for the offer 106 Rallye and the links Denis.

    My fan is OK but it behaves erratically. I have been through this before in an earlier 205 and the problem was fixed by a new blower module.

    The blower module is separate to the fan/blower. It sits further toward the firewall and to the right of the fan (as you face the passenger's footwell) and is just as easy to remove as the fan (pull an electrical plug out and in this instance remove 2 screws that hold the base of the module in the ducting). It is a circuit board sandwiched together with what looks alike a large flat aluminium heat sink. When fitted this aluminium piece projects into the airstream inside the ducting. I guess it acts as some sort of thermal sensing device. (There has been discussion about it before). The circuit board part disappears into the base of the module which looks like it might be embedded in something like a white epoxy.

    Thanks for the threads Denis - in the latter thread you mention improving/repairing the earth to the module in your daughter's 205 (what did this actually involve?) and many of the other comments talk about cleaning up contacts (which I have tried to no avail)

    My actual problem is that I can feel my aircon gets down to a low temperature at the vent but I suspect the fan is not blowing hard enough to make the most of it (compared to say our MI16 which has exceptional aircon). The previous owner spent a fortune on the aircon (I don't want to start another 205 aircon thread)

    I have been quoted $130 to replace the module.

    Thanks for the offers and suggestions. Any thoughts? Does any one know if there any way to repair/bypass the thing and is the module absolutely necessary for the aircon to provide cold air?

    PS In terms of the semantic argument (Denis) the module is listed as an aircon rather than a heater spare. Strange huh?

    Maurice

  5. #5
    Fellow Frogger!
    Join Date
    Jun 2001
    Location
    Sydney NSW Australia
    Posts
    137

    Default

    Maurice

    Quote Originally Posted by mbyok
    ... It is a circuit board sandwiched together with what looks alike a large flat aluminium heat sink. When fitted this aluminium piece projects into the airstream inside the ducting. I guess it acts as some sort of thermal sensing device.
    (There has been discussion about it before). The circuit board part disappears into the base of the module which looks like it might be embedded in something like a white epoxy.

    Thanks for the threads Denis - in the latter thread you mention improving/repairing the earth to the module in your daughter's 205 (what did this actually involve?) and many of the other comments talk about cleaning up contacts (which I have tried to no avail)

    My actual problem is that I can feel my aircon gets down to a low temperature at the vent but I suspect the fan is not blowing hard enough to make the most of it (compared to say our MI16 which has exceptional aircon). The previous owner spent a fortune on the aircon (I don't want to start another 205 aircon thread)

    I have been quoted $130 to replace the module.

    Thanks for the offers and suggestions. Any thoughts? Does any one know if there any way to repair/bypass the thing and is the module absolutely necessary for the aircon to provide cold air?

    PS In terms of the semantic argument (Denis) the module is listed as an aircon rather than a heater spare. Strange huh?

    Maurice
    The module is a simple thryristor or power transistor voltage controller connected to the blower motor. It is operated simply by the slide control on the dash which is a varible resistor (this increases the bias on the power transistor which then turns on). At full speed, i.e., full volts, a relay on the control module board picks up and connects the fan directly to the battery bypassing the controller.

    The module is positioned in the air stream for cooling purposes only, i.e. to allow air across the aluminium heat sink to cool the unit.

    If you think the fan is not blowing sufficiently (at full volts) you could try connecting it directly to the battery to see how it performs.

    As I said in the previous thread, the problem with the control module will most likey be corrosion on a number of rivets in the printed circuit board that from part of the electical earth connections. All I did was check out the whole unit with a multimeter and solder across the head and connection of some of the rivets and also install a short jumper wire in one instance where I couldn't get a good connection.

    The module is an essential part of the speed control of the blower motor, but has no other function. And the reason it fails is that it is continuously in an air stream that is often very damp. You should be able to bypass it by opening the relay on the control module printed circuit board and closing the contacts, so a couple of wires, a remote switch and a battery supply to control that relay would work to bypass the controller... if you must!

    cheers

    Denis
    Last edited by Denis; 17th January 2005 at 01:59 PM.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •