Wiper delay - revisited and proposed option

Hi all,
I know there is much discussion with the wiper delay function and service guides for the OEM delay units on this site.

for years I have had no delay functionality on my P6 and now need it due to using daily and the current weather conditions.

Moving away from the OEM set-up, I propose to buy a small electronic delay unit (initially sold as a delay for turning on headlights after starting car) which has a variable delay setting and to introduce this in series with the connection from the 'Delay' setting on the dashboard switch to the wiper assembly.

I ask if there is any reason mechanically, that simply switching / delaying the power feed to the wiper motor won't permit intermittent operation. I presume the delay mechanism is broken and won't offer any mechanical resistance to the wiper operation.

That said I will also check electrical connections and earth points as well.

Appreciated,
Simon
 
Well, it might work once and then stop but you'll probably need a simple NE555 timer circuit running in astable mode (google it) and drive some kind of non-latching relay.

The very last 3500s and 2200s had some kind of electronic unit.
 
Yes understood - not knowing the details of the mechanism, my proposal was based on there being an internal cam or similar that returned the wiper back to the rest position with a continued voltage feed . Hence by just interrupting the circuit over regular time delays, you simply make the wiper action intermittent.

I thought it was too simple a solution.
Thanks
Simon
 
My wiper motor has a self park system inside it in the form of a cam which pushes a button in the attached wiring plug. You only need to turn the wipers on for long enough to get them going and the self park should stop it in the right place.

Richard
 
I might have a play and see if I can make something this weekend. You can certainly source the parts from Maplin for pennies.
 
Peter - that would be very interesting if not useful to have something to offer the community - this is a real Achilles heel for this car and no obvious workaround or replacement (to me). Most equipment can be replaced by a similar unit from another model or vehicle

Quattro - is your wiper mechanism original equipment or an aftermarket one. I would have thought that the Rover one should be interchangeable with other vehicles. This is where we need sometime who has crossed referenced P6 parts with other vehicles - someone must have more time than me.
Simon
 
Already been done: Automatic Wiper Control Circuit using NE 555 IC

This circuit uses a Darlington driver (pair of transitors) instead of a relay or a high current mosfet. So with a relay instead all need is an NE555, 3 capacitors, 2 resisors and 2 variable resistors. And of course some stripboard to build your circuit on.

The relay solution means you can simply wire it in parallel with your "high speed" wiper switch. It's literally switching it on and off for you.
 
Original -



The button (arrowed) is pushed by the little ramp on the plastic wheel as it goes round. The button operates a little switch in the wiring plug that will turn off the wipers.

Bit complicated that ?? erm.. When the wiper switch is off, there is still a live supply to the motor which will continue to turn the motor. When that little button turns it off, the power is cut and the wipers park at the bottom of the windscreen.

If the screws in there get loose, as they sometimed do, the motor will continue to turn and won't park. (Just in case anyone has that problem :) )
 
Peter,
What you say is Star Wars technology to me. I like nuts and bolts so that you can physically see the mechanism rather than electrical circuitry.

Could you produce a working example as there are many here that would take you up on it. I would commission you to build one , personally.
Much appreciated,
Simon
Alternatively is there another vehicle that has a similar wiper motor we can use instead
Simon
 
Original -



The button (arrowed) is pushed by the little ramp on the plastic wheel as it goes round. The button operates a little switch in the wiring plug that will turn off the wipers.

Bit complicated that ?? erm.. When the wiper switch is off, there is still a live supply to the motor which will continue to turn the motor. When that little button turns it off, the power is cut and the wipers park at the bottom of the windscreen.

If the screws in there get loose, as they sometimed do, the motor will continue to turn and won't park. (Just in case anyone has that problem :) )
So park is when the little ramp is over the button?
 
As long as your wipers have self park you only need to trigger them so they start the sweep and they'll stop by themselves when they get back so a simple delay relay would do the job.

There are many to choose from,

12V Universal Intermittent Wiper Timer Relay - 5 Sec Delay

Just wire it in so when you activate it with whatever switch you've decided to use the normal "wipers on" wiring is triggered, you can do that somewhere up near the switch, no need to go near the motor.

It'll start the wipers going then switch off and they'll self park, then at your desired timing it'll switch them on again. No need to get all complicated about it. :)
 

Without trying myself I couldn't say for sure. I'd say it's worth a punt for a tenner. I'm thinking 5amps will be enough but you might want to run it through a bigger relay as motors tend to have a large transient current when you first switch them on.

Remember what you're asking is very simple - switch on for say 1/4 second, then off and allow the wiper to self park. Then wait a bit and do it again.
 
It looks like the options proposed by Popuptoaster and smokin1942 are what we're looking for. There is another good option by 'smart-screen' and model SS01.

My concern has been whether the existing intermittent control (foam pad / vacumn assembly) is a hindrance to the operation if you introduce an electronic control devise, as above.
Mine is ineffective due to age/wear and the wipers park at mid position when using the 'Delay' option. Hence should they be stripped out or modified to prevent any mechanical restriction.
If not, the options suggested look a simple solution (especially 12V Universal Intermittent Wiper Timer Relay - 5 Sec Delay).
Simon
 
I don't know the P6 stuff that well yet, but I've fitted these on all sorts of things over the years, from Mk1 escorts to Minis. :)

Simple to test, if you can switch the wipers on and then off again and they do one sweep then self park the relay will work, it doesn't need to go near the the Rover intermittent set up, all it has to do is work as if you'd flicked the "Wipers on" switch and then turned it off again.

Alos I didn't relaise my post was duplicating advice already given for some reason my PC didn't load the bottom few posts!!
 
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