Intermittent Wipers - intentional ones that is.

Post by **ColinChandler** » Sun Jun 14, 2009 10:01 pm

Hello all,
I'm in need of a bit of guidance if anyone can help please. Quite a few years ago, I bought a Hella "Screen Wiper Intermittant Control Unit" from a Minor trader who is now no longer in existance. I should have got round to fitting it soner but I didnt - until today that is. I cant get it to work so I wonder if anyone else has fitted one in the past and if they could tell me which wire goes where. The instructions are pretty simple. You basically connect the unit into the wire from the wiper motor to the switch, provide a suppy and an earth to another couple of wires and off it goes. Except in my case it doesnt. Switching the original switch provides continuous wiping as does switching on this control unit.
The unit is a Hella 12v 5WA 001 871 -04 unit with 2 black wires to terminals 53M and 53S, red wires to 2 other terminals and then one other brown wire.
Any help would be much appreciated.
Thanks, Colin.

Post by **MoggyTech** » Mon Jun 15, 2009 4:23 pm

Only thing I can think of, is your car Negative Earth? If not, there may be polarity sensitive components in the Hella unit.

Post by **ColinChandler** » Mon Jun 15, 2009 7:29 pm

Thanks Moggy Tech,
Yes mine is neg earth but I've already juggled the wires about in as many combinations as I can think of just in case the wiper unit was confused. I've Googled the unit too and there was someone else a few years ago who couldnt get his to work either although that wasnt on a Minor. I wonder if I've bought a unit that just isnt suitable for a Minor wiper motor. I suppose I was clutching straws in the hope that someone would say yes I've got one, I've had a look and this wire goes here, that wire goes there.
Thanks for your time though.
Best wishes, Colin.

Post by **PSL184** » Mon Jun 15, 2009 7:35 pm

Has the relay got a wiring diagram on the top of it - If so, can you photo it? The relay would need to be earthed (brown wire?) and would also need a switched live from the wiper switch and a permanant ign live (the 2 red wires?) The 2 black wires should give you pass through operation for continuous wipe and relayed operation for intermittant wipe but I would have thought that you would need a 2 position wiper switch to operate this. I can't see how you would do it from the standard wiper switch.....

Post by **ColinChandler** » Mon Jun 15, 2009 10:32 pm

Thanks PSL,
There's a wiring diagram in the instructions but its exactly as you say. The 2 black wires break into a wire between the motor and the switch so any current goes through the new relay, two red wires are piggy backed together out of the connector for the feed and the brown wire is the earth. In the instructions, it also shows other schematic wires between the switch and the motor and says to find and break into the wire so the low speed doesnt work. I guess all this means its for a twin speed motor and perhaps as you say, the current wiring or switch arent suitable. As I'm an electrical numbskull, do you have any suggestions over what switch I would need? A Minor headlamp switch perhaps with halfway for the intermittant and all the way for continuous? Apols if its a silly suggestion.
Thanks again, Colin.

Post by **PSL184** » Mon Jun 15, 2009 11:21 pm

Thinking a bit more about this, you will need a 3 position switch for this to work. 1 = off 2 = intermittant & 3 = continuous. A headlamp switch would be fine and in keeping with the dash layout as standard.

Post by **ColinChandler** » Tue Jun 16, 2009 6:18 am

That sounds good then. That will give me something to dabble with next weekend.
Many thanks for your help. Its much appreciated.
Best wishes, Colin.

Post by **catswhisker** » Tue Jun 16, 2009 10:38 pm

Just a small point, but worth considering.

I used a Minor light switch when I installed a velman intermittent wiper kit
( from Maplins )
but I wired it so that the first on position (side lights) gave normal wiper
operation , as per original switch, and the second (headlights) position
switched in the intermittent kit.
Keeps things a bit more ' as original'

Sorry I cant help with the Hella system.

BTW. The wiper switch operates in the earth circuit.
I used terminals 4,6& 8 on the side/head light switch. CW.

Post by **ColinChandler** » Wed Jun 17, 2009 9:19 pm

Thanks for that CW. It might be a shame if the MOT tester only pulled the switch to the first position and failed it because the wipers didnt work "all the time."

Thanks to everyone for their help. The forum's never let me down with help for any of my problems.
Cheers, Colin.

Post by **bmcecosse** » Wed Jun 17, 2009 10:30 pm

Just leave a note for the MOT tester - best written on the back of a £10 note!!