Well, I pulled my wiper motor apart today. Took iPhone photos (old iPhone 3G - not high quality, but good enough if anyone wants them), but I'm not keen on setting up an image hosting account.
The long and the short of it is that my wiper motor looks great inside, but still doesn't self park.
I pulled the motor off. Undid the three screws through the firewall first, then undid the nut on the cable. I found the circlip on the back and managed to remove it. Used a 1/4 socket as a drift to knock the shaft back through, then undid the 4 bolts on the case cover. Found it handy to do it in that order - it was much easier to get at the bottom 1/4" bolts on the cover.
With the cover off and the wheel knocked free, I discovered some quite extraordinary things. First off, my park ring was almost spotless, and practically brand new.
Secondly, one of the three prongs (brushes?) was bent badly away from the ring.
In order, from the prong/brush closest to the centre of the ring out (so, from the park prong/brush out) , the park ring was definitely contacting. The next brush/prong was bent away, and was also a bit black/greasy (I sanded it a touch to restore that coppery shine). The third one wasn't near contacting the park ring. I bent all three out, hoping they'd touch the ring (I'm pretty confident they're touching - I'm sure that at least the inner two would've been pushed down by the park ring when it was reinstalled).
There was another surprise. There was old grease in the bottom of the motor, but no tide mark, and no rust.
Regardless, I still drilled a small hole in the bottom to ensure that I don't have water pooling in there.
So, feeling encouraged, I reinstalled everything. I put the wheel in the body (a little grease to help it in), I put the cover on (heaps of grease at the top end), I put the thrust washer and circlip on the back of the motor (to hold the wheel in), I screwed it to the fire wall, and I did up the cable nut. I put the bonnet down, jumped in the car, and promptly found that nothing had changed.
I'd wasted two hours.
So... Going through the checklist Mr Smidt's given on page 4, I've got everything right. Ring's good, connector's working, wiper motor is earthed (well, I believe it's earthed! It runs!), and I'm using a single speed motor (it's not a light switch). The only thing I can think of now is that it's wired incorrectly. Which, given my experience when adding relays to my headlights, should probably have been my first suspicion.
When I bought the car, it only had two wires on the wiper motor. I added a third wire, hoping it would self park, but that didn't work. Using the Doc's sketch and orientation, and but knowing it's only a single speed motor (so there are only 3 connectors on the motor), I've got permanent power at the top left connector, the switch is wired to the top right connector, the bottom left connector is a little pig's tail earthing to the wiper body, and there is no bottom right connector. I've looked at the schematic, but it doesn't seem to give any clues as to which wire should connect to which pin...
drmini in aust wrote:
Any tips would be appreciated! And any photos
can be emailed.
I do know that the power is coming from the switch to the wiper, rather than to the wiper then earthing through the switch, as most of the wiring diagrams I've looked at seem to indicate as the preferred method...