Intermittent wipers, with wash wipe too !

[Steves_TR6]

Somewhat bored that the freezing cold weather has been replaced with very wet weather..... I thought i’d mess about with TR wipers!

a few years ago i built and fitted a maplin intermittent wiper kit to my TR6 which worked quite well

however i saw a VW99 intermittent wiper relay seemed to offer programmable wipe delay AND wash wipe..... so an experiment was in order :-)

bought an aftermarket Cargo relay that replaces the vw99 and read how it works.

all good except the trigger for the 99/Cargo is a positive pulse which starts the delay function

the TR park switch goes to 0v at park and 12v during the wipe stroke, so i added an opto-isolator to take this 0v at park and turn it into a 12v at park ‘pulse’

thus the Cargo can ‘hear’ this and start a delay period, after which it can deliver a 12v pulse to the low speed coil to set it in motion, the park then finishes the sweep

next challenge is that that with the wipers turned off the park switch shorts the wiper motor slow coil to earth to stop the motion dead, but the Cargo has a set of n/c contacts to accomodate this

prototype completed and it works !

the last aspect is a wash/wipe input on the Cargo that provides 7 secs of wiper power when the washers are activated, not tested this on the car yet but does appear to work on the bench

total cost of the kit is under £15, and no permanent mods to the original wiring !

so that was my morning in the workshop ..... i’ll report back after further testing ....

 

 

[Richard Pope]

Sounds really great. Don't suppose you can blow up the paperwork so one can read it and / or chop int exploded sections.

Thanks.

[Steves_TR6]

The paperwork was not for the relay but just an explanation of how the standard TR6 wipers operate.

i’ll see if i can post a link....

[Andy Moltu]

Could you have used a relay to make an earth  connection  when it pulses?

[Steves_TR6]

2 minutes ago, Andy Moltu said:

Could you have used a relay to make an earth  connection  when it pulses?

Yes i did consider that Andy, but preferred the ‘no moving parts’ opto-isolator

steve

[Lebro]

A transistor would also do the trick !

Bob.

[Steves_TR6]

10 hours ago, Lebro said:

A transistor would also do the trick !

Bob.

Good point Bob!, i might experiment as that would be simpler

 

steve

[harrytr5]

That sounds just the thing I would want Steve. If you do a kit I will buy off you.

Regards Harry

[Steves_TR6]

40 minutes ago, harrytr5 said:

That sounds just the thing I would want Steve. If you do a kit I will buy off you.

Regards Harry

I do need a new hobby so of it works well and reliably i’ll make you one Harry!

[cvtrian]

1 hour ago, Steves_TR6 said:

I do need a new hobby so of it works well and reliably i’ll make you one Harry!

And if you make several, please add me to your customer list!
Thanks
Ian

[Bfg]

Very clever indeed. I wouldn't know where to start do such a thing. My dad was an electronics engineer but he never taught me about such things, so I was planning on finding and swapping out to another make of wiper system that already had the intermittent feature and different speeds.

Bottom line ;  I'd be very interested too if you reckon it would work with 4A wipers.

..which sounds like you'll soon have enough orders for a first batch. 

Thanks, Pete 

.

Edited February 18, 2021 by Bfg

[Alfrom]

Looks a great idea and simple too.  What's not to like?  And yes please if you go down the kit assembly route.

Pierre

[Steves_TR6]

Haha, i was not planning to make these for others but .... maybe !

weather set to improve this afternoon and be positively nice on Sunday, so i’ll install the unit and see how it performs in the car

if all is well then i’ll consider making a small batch.

i’m just an enthusiast in a shed so any units would be provided on a ‘cost plus a pint’ basis without warranty :-)

steve

[Richard Pope]

Or perhaps just a list of parts and a simple wiring diagram for those that can do it themselves .... thanks in antocipation.

[Steves_TR6]

29 minutes ago, Richard Pope said:

Or perhaps just a list of parts and a simple wiring diagram for those that can do it themselves .... thanks in antocipation.

Yes, i’ll certainly do that once it’s tested Richard

[Richard Pope]

Thanks again.

[Steves_TR6]

Fitted and tested the Intermittent WashWipe unit this morning and Success!

i did consider wiring the unit to replace the ‘slow’ wipe setting but decided instead to add a toggle switch at least initially.

so the original wash and wipe switch(es) work as originally intended but new functionality is added via the toggle switch

with the wipers off the toggle switch turns on intermittent wipe

with intermittent wipe turned on operating the washers also provides 4 or 5 wipes

perfect!

here’s a video of the testing :-)

https://1drv.ms/v/s!AhDJKiWSrX7_v32wp60-j5CGk2WB
 

steve

[Richard Pope]

7 hours ago, Steves_TR6 said:

perfect!

here’s a video of the testing :-)

https://1drv.ms/v/s!AhDJKiWSrX7_v32wp60-j5CGk2WB
 

Agreed.

[Steves_TR6]

Thanks

i’ve also tried wiring the unit to replace low speed with intermittent, this work perfectly too and in fact i prefer it as there’s no additional switch needed!

i’ll test some more and then post details or order parts for a few ‘kits’ 

steve

[harrytr5]

Well done Steve. My TR5 is crying out for one of those. My switch has three cables attached to it and the TR6 has four so might be a problem.

Looking forwards to your testing results and maybe a kit from you.

Regards Harry

[Kevo_6]

On 2/20/2021 at 10:10 AM, Steves_TR6 said:

Fitted and tested the Intermittent WashWipe unit this morning and Success!

i did consider wiring the unit to replace the ‘slow’ wipe setting but decided instead to add a toggle switch at least initially.

so the original wash and wipe switch(es) work as originally intended but new functionality is added via the toggle switch

with the wipers off the toggle switch turns on intermittent wipe

with intermittent wipe turned on operating the washers also provides 4 or 5 wipes

perfect!

here’s a video of the testing :-)

https://1drv.ms/v/s!AhDJKiWSrX7_v32wp60-j5CGk2WB
 

steve

Excellent project Steve, well done. I would be interested in this also, in either list of products and diagram or purchase a unit from you.

Many Thanks Kev.

[Steves_TR6]

Thanks guys

i already realised that the tr4/5/cp/cr variations might be a challenge

but i’m confident this unit will work with them all as long as the park switch arrangement work the same way

i plan to investigate this week and report back !

steve

Edited February 21, 2021 by Steves_TR6

[Steves_TR6]

Whilst out cycling this morning i though to myself ‘if i take Bob’s suggestion and use a TRansistor i might be able to fit it internally in the relay box’......

so that’s the next experiment as it would yield a much neater solution :-)

i need to research a suitable transistor , i’m thinking pnp to take a negative trigger and switch a positive output, any suggestiins Bob?

steve

Edited February 21, 2021 by Steves_TR6

[Lebro]

Either NPN or PNP can be used to invert an input signal, it rather depends on what the transistor is driving.

Can you show how you have wired in your opto as the output stage of an opto is really just a transistor.

Happy to do a sketch of a transistor circuit, just need to know what it will be driving.

Bob.

[Lebro]

Something like this -

 

Diode is to protect base emitter junction from transients. 1N4004 etc.

Any similar PNP transistor would do, this was just one I knew about. IC max 1A, HFE 50

Bob.