410 windscreen washers

[livermoreb]

Does anyone have a wiring diagram for the windscreen washer on a 410, or indeed does such a thing exist?

I have a diagram for the 407/8 in the manual but that doesn't seem to have a screen washer, and I have one for the 411 but that doesn't appear to be the same.

The 411 diagram shows a green wire going from the switch to the motor and a black wire going to earth/ground. My motor has a green wire to the + terminal and a black and green one on the other.

The washer is not working so to test it I disconnected both wires and attached one terminal direct to earth and the other direct to the + side of the battery. Hey presto it worked so the problem is not the motor. I tried it again with the black and green wire connected and the + side fed direct from the battery and it did not work.

From this I concluded that the earth was at fault so connected the black and green terminal direct to earth and reconnected the green wire to the + terminal on the motor. When I turned on the ignition to test if it now worked, the washer sprang into life and would not stop!

Has anyone else had this problem?

[guymd]

I'm afraid your explanation isn't clear to me. For example, the third paragraph mentions parts without being specific enough for me to see the picture.

Perhaps you could attach a specific "label" to each part. Is a terminal part of the washer motor, or is it a battery terminal? Is a + terminal on the switch, the motor, or the battery? Do terminals on the switch and motor both have + and - markings?

I'd like to help, but when I tried to sketch it out following your description, I got lost.

Thanks,
Alexander

[livermoreb]

Thanks Alexander. I agree it is a bit complicated. I have tried to amend my description to give a more comprehensive explanation below:-

The 411 diagram shows a green wire going from the switch to the motor and a black wire going to earth/ground. My motor has a green wire from the switch to the + terminal and a black and green one on the other.

The washer is not working so to test it I disconnected both wires from the motor and connected one of the terminals on the motor direct to earth and the other direct to the + side of the battery. Hey presto it worked so the problem is not the motor.

I then disconnected the wire I had put on the earth terminal on the motor and reconnected the black and green wire to it and kept the terminal on the motor marked + directly connected to the + terminal on the battery and it did not work.

From this I concluded that the earth was at fault so connected the black and green terminal on the motor directly to earth again, disconnected the wire from the + terminal on the battery and reconnected the green wire to the + terminal on the motor. When I turned on the ignition to test if it now worked, the washer sprang into life and would not stop!

I hope this makes it clearer.

Bob

[PEU186F]

The 410 windscreen washers are actuated by a simple push switch which is mounted on the back of the fiendishly complicated wiper switch (which by the way has to achieve a polarity reversal to the wiper motor so that it reverses to the park condition)

My memory tells me that this push switch applies an earth to the black and green wire that you mention coming from the washer pump, so if I'm correct there should be a black wire (to earth) and a black and green wire (to the washer pump) coming from this push switch. There are inumerable wires coming out of the wiper motor switch itself

The normal colour coding convention on vehicle wiring is that green wires are normally live when the ignition is on. So it appears to me that there is a live supply to the washer pump all the time the ignition is on. The colour coding of the black and green wire implies that it is earthed, via the push switch, when the washers are required, which completes the circuit.

Your description of the 411 wiring diagram, that the green wire to the washer pump comes from the washer switch, and there's a black wire from the pump to earth suggests that the 411 arrangement is entirely the other way round, i.e.
its the feed that's switched on the 411, not the earth.

It is relatively simple to get to this push switch if you need to. First remove the padded strip that runs across below the dashboard. Most of the screws are fairly obvious but my memory tells me that there are two that are not so obvious at each end of the strip towards the front of the car. A slight complication is that the fresh air inlet control is mounted on this strip, so you have to take that off the strip as well if you need to remove the strip completely, but you may be able to work round it.

It's also, from memory, relatively easy to take the whole wiper/washer switch out, if you need to. The knob is, I seem to remember, held on to the shaft by a spring loaded plunger, which you press in with a nail or whatever from underneath and the nut that holds the switch on will then be obvious to you. But don't do this before you take aforementioned padded strip out as you need to take careful note of what wire goes where on the switch as soon as you possibly can as the 407/8 wiring diagram is no help whatever if in this regard.

If you need to get your head under the dashboard I would counsel removing the drivers seat AND both its runners, which are otherwise inclined to attack you.

I hope this is a help

Roger Morrall

[livermoreb]

Many thanks for your comprehensive response Roger. This explains why the pump was on continuously when I turned on the ignition having connected the earth side directly.

I will have to investigate further but, if the switch is at fault, do you think it would be possible to repair it or are there new ones available? If not it might be simpler to install a new, separate switch for the washers.

[PEU186F]

Bob

Quite so

My 410 parts manual tells me that the Lucas part no for the wiper switch is 31847 and that for the washer switch is 31513. They also bore the Lucas designations PRS9 and 15SA respectively

I attach a screen shot of a Lucas catalogue which show what they both look like. It appears that put together they also bore a composite part no 31940.

I recall the washer switch as a very simple cheap looking item, with screw terminals. Just as depicted. The wiper switch shaft passes right through the switch and is spring loaded to act on the press to make switch when pushed in. Any simple push to make switch would probably suffice as a replacement if you can mount it.

Rovers, Rolls Royce and others used similar reverse to park wiper motors and presumably similar wiper switches, so replacements may be available. But I seem to recall that my Pa's Rover 90 had a separate washer switch so that may be rarer

Note the anti twist "wings" on the wiper switch, I think these go behind the metal framing of the dashboard ( as opposed to the wood side) but I cannot really remember.

Good luck

[livermoreb]

Wow, what a Heath Robinson-esque contraption!

I will obviously have to remove the switch as you suggested and try to work out if it is that which is malfunctioning or if there is a problem with the earth or live feeds. Maybe just a loose connection to the washer switch.

Thanks again for your help.

Bob Livermore

[Giles]

Is it something like this?

SWITCH (Windscreen wiper & washer) (UD4667U)

This worked with a 408, obviously converting the vacuum switch to electric

[livermoreb]

That's exactly it.

Thanks Giles