Just seen this on late bay...credits to the poster “Snotty “ on that forum....
Wiring: a diagram I'd previously done for Other Purposes shows the connections to the delay relay. You'll need to find VW relay "99" or "197", either from the scrapper or from fleaBay. There is a Bosch equivalent. VWH and JK appear to sell the fixed-delay "19" job. With the variable delay, you flip the switch to get the wipers moving, then turn it off, wait a bit, then turn intermittent operation back on again. It magically remembers the delay, at least until you disconnect the power. What could be simpler, eh, I ask you?
VW Wiper Delay XA.jpg
Everybody needs an intermittent wipe function (which was actually an option on some Bays, it seems), but equally useful is an arrangement that fires up the wipers while you're operating the washers. You squirt, the wipers run and keep running for a few strokes after you've let go of the washer button. No more stalk-fiddling.
For intermittent, I'd used a Hella delay wipe relay mounted under the headlight switch. This works really well, with its little twiddle-it knob, but it won't operate the wipers. An intermittent relay as fitted to early Golfs and the like will, and the later relays allow the delay period to be varied using the intermittent switch. Earlier ones have a fixed delay. I don't know what it is. If you're slick, you can mount the relay in one of the spare positions in the fusebox, as I did.
All of these fandangos need a few simple mods to the existing wiring. Specifically, you need to chomp through the +12V supply line to the motor "slow" winding (53). You'll then end up with two "new" connections: the end the goes to the wiper switch (53S) and the end that goes to the motor (53M). The reason for this is that you're going to be turning on intermittent operation with the wiper switch is "Off", which means the motor park switch is in charge. The park switch keeps 12V on the motor until it reaches the parked position. It then does two things: it disconnects the motor supply and then shorts the motor winding so that the motor stops quickly. If you don't mod the wiring, dabbing 12V on the motor line would just cause the motor fuse to pop. You'll get through one fuse per wipe. The intermittent units incorporate a changeover relay that disconnects the idle switch, gives the motor a 12V kick, then drops back to normal park operation so that the wipers stop in the right position.
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Sorry I couldn’t get the wiring diagram to appear.
Also just heard back fromRevolution electronics in USA ( so quick to reply) they confirm that their module could operate with an additional remote push button to give a single sweep, connected into 12 v slow speed wire. They say that the module would just think the power had gone on for a moment and then off again. Even I can grasp that
Apologies for lengthy post.