Elan Sprint Intermittent Wiper Control

[stugilmour]

I don’t have a Sprint diagram to hand so cannot be sure, but I would think the Sprint and Federal Plus 2 would be wired in a similar fashion. My understanding is the flat switch configuration is the same. To clarify, my car has one momentary-on switch for the window washer and a separate three position switch to control the standard Lucas two speed wiper motor.

One thing to watch for is on various models Lotus strayed from what became the British Standard AU7a 1983 wire colours in the two speed wiper circuit. They also changed the wire colours over the model range. This makes tracing the circuits and/or using general references for other British cars a bit challenging. IIRC one of the original wires may even have changed colour at the main firewall bullet connector located down by the pedal box; can’t 100% if this was in the wiper circuits but you get the idea. I ended up using the standard colours when I re-wired the car.

The SmartScreen is set to intermittent mode exactly the same as Gherit described for his Golf 2. When I was looking around the ‘net for this feature I saw several folks had used a VW/Hella relay to add this feature. Pushing the window washer flat switch produces three wipe cycles, which is perfect. If it is just a very light shower I often press this switch quickly to just get three wipe cycles without the squirter pump putting anything on the windshield.

The biggest wiring hassle for my LHD car was running a new wire from the squirter pump across the firewall to the SmartScreen mounted on the right (passenger) side of the firewall by the wiper motor. All the other required wires were accessed within the wiper loom. Pretty easy and no behind the dash stuff.

Lastly, a top tip. If your wiper motor connections are just separate female spade connectors, this plug prevents any future wiring errors.

http://www.britishwiring.com/Wiper-Moto ... p/c805.htm

[miked]

From an old post on most satisfying upgrade.


Wipe using Light Stalk!
Last night I did a job that I think will be handy. Rather than fit a timed wiper control that you keep fiddling with, I made the flash function on the dip/main beam stalk to carry out a wipe. It has been discussed before about making this work. I pulled the standard switch out to find a 4 wire device with flash function throwing a positive signal in the dip position. So you would need to have the light wedge switch (fully) operated and side lights on (if you did not pull the vac switch). Perhaps no bad thing having side lights on in the rain?
Looking closely I could have carefully cut the link and soldered an extra wire to create an isolated independent switch. However, looking in my spares box I found a Triumph 5 wire stalk unit with separate flash circuit. Using this I powered a relay with changeover contacts (common, NC and NO). Using just 3 wires you can break the park circuit on the dash switch (electric brake) and feed a low speed positive. When operated this flick puts the wiper motor onto its park circuit supply to complete the wipe. So now, without taking my eyes off the road I can give a swish by just a pull on the stalk under my hand.
In the past when I have fitted timed controls they have had two relays or two switches. One for breaking the dash park circuit and one for the pulse to power up. It can however be done with the single relay.

Mike 

[RichardS]

Thanks for posting that Stu. I actually found your post when searching previously.

It does look a great option - I really like the idea of being able to combine it with the wash switch, as well as the fact no additional switches are required so the dashboard looks stock.

I note that you have rigged it up on a +2 which has slightly different wipe/wash switch configuration - yours is a combined switch unless I'm mistaken. The differences shouldn't be insurmountable, and it looks like SmartScreen may have good technical support. I think I'll give them a call tomorrow to discuss.

Thanks again.

Did you manage to contact Smartscreen? I looked into intermittent wiping a few months ago, and liked the look of the Smartscreen as it doesn’t need a separate switch to operate. However I tried ringing and emailing Smartscreen on several occasions but had no reply so hesitated in ordering from their website. I think their website looks like it’s been updated recently so perhaps all is ok? Holden etc are out of stock apart from the positive earth version.
Richard

[stugilmour]

Quick Followup.

Checked my notes and noticed the SmartScreen installation instructions are not on their web site. I found a pdf here

https://www.moss-europe.co.uk/media/pdf ... ctions.pdf

Maybe Moss Europe would have stock?

From my notes the model I purchased is SS05/P. IIRC the P means the squirter pump is switched on the power or positive side. I do not recall if this is the same with stock Lotus wiring, but that is how I rewired my car. Maybe check that before ordering.

Dr Google freaks out a bit as apparently there is Microsoft software with the same smartscreen name.

Their web site is here with a hyphen…

https://www.smart-screen.co.uk/product- ... pe-on-wash



HTH

Stu

[RichardS]

I sent an email to Smartscreen and had a prompt reply to say their units are made to order and take about a week.
Might add to my list of winter jobs!
Richard

[Bodmin]

From an old post on most satisfying upgrade.


Wipe using Light Stalk!
Last night I did a job that I think will be handy. Rather than fit a timed wiper control that you keep fiddling with, I made the flash function on the dip/main beam stalk to carry out a wipe. It has been discussed before about making this work. I pulled the standard switch out to find a 4 wire device with flash function throwing a positive signal in the dip position. So you would need to have the light wedge switch (fully) operated and side lights on (if you did not pull the vac switch). Perhaps no bad thing having side lights on in the rain?
Looking closely I could have carefully cut the link and soldered an extra wire to create an isolated independent switch. However, looking in my spares box I found a Triumph 5 wire stalk unit with separate flash circuit. Using this I powered a relay with changeover contacts (common, NC and NO). Using just 3 wires you can break the park circuit on the dash switch (electric brake) and feed a low speed positive. When operated this flick puts the wiper motor onto its park circuit supply to complete the wipe. So now, without taking my eyes off the road I can give a swish by just a pull on the stalk under my hand.
In the past when I have fitted timed controls they have had two relays or two switches. One for breaking the dash park circuit and one for the pulse to power up. It can however be done with the single relay.

Mike 

That looks like a great idea. Can’t quite get my head around the wiring though.

[miked]

No worries. I should have the diagram in my book with some notes. I will dig it out tomorrow.
Cheers Mike

[billwill]

Because windscreen wipers are (usually) designed to self park, which works by continuing to power the motor until a wiper reaches a "park-now" gap, when in the "gap" the car circuitry normall short-circuits the motor to make it stop quickly.

The basis principle of intermittent wiping is to power the motor for a short period (just long enough to move the wiper off the gap). This is usually done by energising a relay for a short period at the desired rate such as once every 5 seconds etc.

So the electronic circuit usually consists of a slow pulse generator, closing a relay for about a half-second at the desired interval.


So apart from power lines to the electronic board, it only needs three-wires (from the relay) going to the parking circuit of the car's wiper motor. the Normally closed position is inserted into the circuit that shorts the motor, and the normally open (closed by the pulse) feeds power to the motor fir that brief interval.

I see no need whatsoever to have other relays to make major changes to the wiper circuitry.

The electronic circuit is usually a simple NE555 chip (a timer) in a standard configuration.

[miked]

See rough sketch from my record book. 2017.
Shows one relay and 3 wires doing the task. Sends pulse to move wipers on to live park circuit to complete throw. Plus drops back to emf brake to prevent overshoot and park up. So does not alter the function of the circuit. Simples. Working since 2017.

[Bodmin]

I decided to go with the Retronics RWTM windscreen wiper module.

It wasn't the cheapest at £54.99 + £4.99 P & P, but I was very impressed with the technical help from Andy Winters who furnished me with the correct wiring diagram as well as assured technical support.

When I ordered the unit I requested he delay sending it for 10 days as I was off on holiday. When I arrived home it was waiting for me having arrived the same morning.

Fitting was very simple. Remove the Red/Light Green wire from the wiper switch, connect this wire to the Brown wire on the control unit. Connect the Orange wire from the control unit to the terminal on the switch where the Red/Light Green wire was previously fitted. That's about it apart from connecting the other control unit wires to earth and a convenient switched +ve supply.

I jury rigged the system to check it worked, and it worked perfectly. The rotary switch has discreet positions for 0ff, and sweep intervals of 2,3,4,6,8, and 12 seconds. The wiper switch itself still overrides the intermittent wipe on with low and high speed.

The rotary switch has an extended stalk which can be cut to any length. Im going to fit it to the under dash trim next to the transmission tunnel.

[slowsprinter]

Hi Guys
I just want to add my tuppence to this thread with my experience. I am just fitting a new dash to my project and wanted to future proof my car with an intermittent wipe upgrade (72 Sprint DHC).

As a result of this thread I placed an order with Smartscreen in mid November. Mainly because their solution did not require another switch. After about 3 weeks nothing had arrived so I contacted them. A Jonathan Stafford-Mills replied to my email (eventually) to say that it had been dispatched by Royal Mail and there was an issue so he said he would send a replacement. I replied that would be fine. Another 3 weeks passed and still nothing. I know there are strikes on at the moment so I thought I would give them plenty of time. I have just cancelled the order and asked for a refund which Jonathan replied straight away to say that a refund will take 5 days. I hope this is the case. Therefore, I have to report that I am very disappointed with this company. I don't mind if they have issues as long as they keep you informed. I had nothing from them until I prompted them.

I will probably now go for the option that Bodmin has reported on and fitted from Retronics. I will just have to find a place on my dash for the extra rotary knob this kit requires. Just my observations with Smartscreen!
Ian