505 electric window spruce up
  • Register
  • Help
Results 1 to 4 of 4
Like Tree5Likes
  • 4 Post By robs
  • 1 Post By robs

Thread: 505 electric window spruce up

  1. #1
    Fellow Frogger!
    Join Date
    Nov 2010
    Location
    Blue Mountains, NSW
    Posts
    421

    Default 505 electric window spruce up

    A while since I posted anything here. Always juggling time.

    The windows in my '85 505 GTI (S1) had become slow/unoperational with the years and I spent a while this weekend looking into it. A few interesting things that might help other people.

    A number of people here have mentioned success with fitting relays, so I started looking into the switches and wiring.

    Advertisement


    Dismantling the switches was easy enough and they were in great shape -- nice clean contacts that are just like a hand-operated relay.

    The wiring was "interesting". I hadn't previously traced where they went. The wiring diagram shows them going to a "Connection board". Turns out that it's a big common "bus" for power and ground with 4 sockets in the top for accessory connections. It's not hard to get at -- the glove box light is mounted to the underside of the same bracket it's mounted to.

    The grounding from this panel all goes through a beefy wire (M92) that grounds to the chassis on a common grounding terminal just above the driver's left knee.

    Similarly, the accessory power all comes from wire 92 fed from a shared fuse (F2).

    Checking voltage drops along the wires showed I was losing about 1V from battery to switch, and 1V from switch to ground. A 12V motor running at 10V is hardly optimal. Further voltage drop tests implicated the fuse and relay on the feed side and the connection board on the grounding side. Installing a new fuse gained me 0.5V, so that was worth doing. I swapped the rear window demister relay with the accessories relay and that gained me another 0.25V or so. I unplugged and replugged the sockets and several of the wires on the connection board and that gained me nearly another 0.5V on the grounding side.

    This done, the back windows were now working tolerably well. Driver's window was still as slow as a wet week. Passenger window hummed, but didn't move.

    Took out the driver side door lining and hooked a battery directly to the motor. Still slow. Hmmm. Should have started with this.

    So out with the motor and regulator and, even with no load, it only moved slowly under battery power. Trying the window in its channels, all was smooth.

    The motor probably isn't officially serviceable, but there are 4 tabs that can be straightened to allow the brush holder to come off the end, and two pins holding the housing and magnets at the gearbox end. If you dismantle the motor, make sure you mark the body as it can go together two ways.

    It might be possible to dismantle the gearbox, but I thought I was already nearing my luck quota and didn't want to get too adventurous.

    With the motor apart, there was quite a bit of dry yellow "plastic" that once was grease. The motor did not turn easily by hand. Started by squirting a bit of oil into the gearbox end while turning the motor and it soon freed up nicely. A bit of grease on the bushing in the brush housing and a light buff of the commutator with wet and dry and it was ready to go together again. Now we're at the tricky bit because there isn't any provision for holding the brushes back for reassembly.

    Measuring things up, the brushes need to be pretty well all they way back. It took a bit of head scratching but, in the end, it worked out easy enough. I looped a fairly stiff cable tie (not zipped) on the bottom half of the brushes and it held them all the way out. There was room on the top half of each brush for the commutator to engage while there was still clearance for me to pull the cable tie out. Was kind of amazed that it worked, but it worked first go. It also worked second go when I realised I'd forgotten to install the wavy washer.

    Reassembled the driver's door and the window now fairly flies up and down. Great.

    Moved on to the passenger side -- which wasn't budging at all. Giving the window a helping hand between hums from its motor, I gradually got it down about 3" and suddenly it was able to go down and up to that point smoothly. Looking at the Bailey channel was not a happy sight. Rust was pinching the sides of the channel together at the mirror.

    Fortunately, it wasn't as bad as I feared. Nothing was rusted through, it's just that the scales of rust had nowhere to go and just 1mm of pinch is too much for a happy window. Have scraped the rust and hit it with some prep/converter. Have just applied some paint and thought I'd type this up while waiting for the first coat to dry.

    Morals:

    • 30+ year old connections might appreciate it if you give them a little activity -- i.e. the connection board. Side effects of my fiddling: the dashlight is brighter and the heater fan, which had been an on-again/off-again character, is now responding as it should.


    • The switches seem well made. If the connection board doesn't get your windows going, try hooking a battery directly to the motor. If that works fine, it's time to look at the wiring/installing relays, etc. If it doesn't work fine, time to test your luck with the cable tie dodge.


    Have fun,

    Rob.

  2. #2
    Member
    Join Date
    Oct 2017
    Location
    hawthorn melbourne
    Posts
    73

    Default

    Fitting relays worked well for me,but you say connecting the battery direct to the motor didnt make any difference so it wouldnt make any difference in your case .Glad you got it sorted in the end.

  3. #3
    1000+ Posts Beano's Avatar
    Join Date
    Mar 2004
    Location
    Brisbane
    Posts
    2,992

    Default

    Thanks for going to the trouble of posting that info, Robs. Very handy.

  4. #4
    Fellow Frogger!
    Join Date
    Nov 2010
    Location
    Blue Mountains, NSW
    Posts
    421

    Default

    No worries Beano, all that info wouldn't have stayed long in my memory. Might last a bit longer here.

    And yes, Julian, I'm very glad to have working windows all around. If nothing else, it saves embarrassment at boom gates and RBTs.

    Have fun,

    Rob.
    Doush_504 likes this.

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
  •