Wiring of window motors

[John Larkin]

I had my window motors rebuilt a few weeks ago, and I tested them today before re-installing them. I cannot get them to work. It's a public holiday here in Ireland today so I cannot contact the electrical engineer till tomorrow.

Can anybody explain the wiring to me? The Lotus workshop manual shows three wires:- brown/green, brown/red, and an earth wire. I have four wires:- brown/green, green, a second green wire, and an earth. Buckland's book, in describing the original Ford wiper motors, instructs that the two wiper parking control wires emerging from under the brown cover be removed as they are not required when the motors are used for the windows. However, one of them is still in place in each of my motors. I assume that the two wires emerging together from the plastic capping are the motor wires.

I tested the motors by connecting the earth wire directly to the negative terminal on the car battery, and each of the other two motor wires separately to the positive terminal expecting that the motor would spin one way and then the other. Nothing happened with either motor.

Can anybody please advise me on how to wire these up?

John Larkin

[garyeanderson]

The greens get tied together on the motor and well the black is ground and the brown/green is by itself.

[SADLOTUS]

Hi John,
I too had great trouble getting my motors to work properly, it nearly drove me NUTS!!.
There are lots of threads telling how people ran thick braided earths back to good ground points. For me this made no difference, as I believe the earth changes from the black to another wire when the switch is pushed up or down.
The motors worked perfectly on one side of the car but not on the other or on the bench - as I thought they should! It was down to a dodgey switch and my missunderstanding of how I thought they should logically work.
Yes, for one side I removed the wire from under the brown cover - made no difference. All I can do for you is tell you how mine are wired and hope that helps a little.

Sorry there's a yellow wire! I blame it on the previous owner.
You can swap the wires if your switch is upside down - mine was.

Good luck... although this may just makes things more confusing!

Paul

[John Larkin]

Thanks for the quick replies!

I wired the two greens together as a pair. When I connected the paired greens to one battery terminal and the brown/green wire to the other terminal the motor ran. When I reversed the connections the motor ran the other way. The earth/ground wire does not seem to do anything.

Gary, I notice that there is no earth/ground wire on your motors. Were they wired into the car without such a connection?

I cannot reconcile the arrangement on the Lotus wiring diagram with the actual wiring for these motors.

John Larkin

[garyeanderson]

The wiring in the door is the same on both sides. N/G goes to N/G and N/R from the switch goes to Green.

[garyeanderson]

The black wire (earth) goes to the spade conector on the fiber board cover. This is the same location that you are using for the black wire. Three wires with one of them ground is not that difficult. The black wire is the ground and used in conjunction with the switch.

Gary

Thanks for the quick replies!

I wired the two greens together as a pair. When I connected the paired greens to one battery terminal and the brown/green wire to the other terminal the motor ran. When I reversed the connections the motor ran the other way. The earth/ground wire does not seem to do anything.

Gary, I notice that there is no earth/ground wire on your motors. Were they wired into the car without such a connection?

I cannot reconcile the arrangement on the Lotus wiring diagram with the actual wiring for these motors.

John Larkin

[John Larkin]

Thanks again Gary.

I see a black cable coming from the loom in your last two photos. It seems to connect to the motor. Does it, and where? I also see what looks like white cable. What is that for?

Regards,

John Larkin.

PS I'll be in Boston/Cape Cod areas between August 19-24. Like to meet for a beer?

[garyeanderson]

The white wire is a rig for the earth wire I think, its not on your window motor so its not of concern. more photos

Right side motor

Left side motor


I live about half way between the Cape Cod Cannel and Boston, 7 miles east of the Route 3 highway. Stop by and see the collection if you have time. I don't drink at all any more, I gave it up and took up the Lotus adiction full time 24 years ago. we can go and get steak tips at Jamies Pub though, they serve beer too, and may even have something fair along those lines.

[nhhiker]

I can tell you the steak tips at Jamies Pub are just great. This seems to be Gary's place of choice. The trip to his home will be well worth it.

Gary, the plus 2 has almost 1000 miles on it! I am driving all the time now. It is only getting better!

Bill Fralick

[garyeanderson]

I can tell you the steak tips at Jamies Pub are just great. This seems to be Gary's place of choice. The trip to his home will be well worth it.

Gary, the plus 2 has almost 1000 miles on it! I am driving all the time now. It is only getting better!

Bill Fralick

Bill

Please stop rubbing it in, I know a mistake when I make it.

Gary

[CBUEB1771]

I'll be in Boston/Cape Cod areas between August 19-24. Like to meet for a beer?

Several of us get together for lunch in Ayer, about 45 minutes drive WNW of Boston, at noon on Wednesdays. In addition to Elans we count a IX, a few XIs and a gaggle of Elites in the "collective" ownership. We'd be happy to have you visit. If that doesn't work I'll try to stop be Jamie's Pub.

[John Larkin]

I have my windows working! I am really grateful for the help that I got from Gary and Paul.

I will not be able to make it to Ayer, but I'll definitely meet up with Gary in Jamie's Pub. Gary, I'll telephone you from New York over the weekend of the 9th/10th August.

Again, thanks for the help given.

John Larkin.

[billwill]

Surely Windscreen Wiper motors do not have the extra reversible winding (3-wire arrangement), so would need a double pole changeover switch to actually reverse the polarity of the two effective wires.

The extra wires on a Windscreen Wiper motor are for fast & slow, not for forwards & backwards.

[oldelanman]

The extra green wire was for self parking when used in it's original role as a wiper motor - I think self parking predated 2 speed operation. The motor was earthed via the wiper switch when running and when switched off the earth was maintained via the extra wire through a slip ring on the output gear until the wipers reached their park position. (See attached photos). In this application as a window motor the extra geen wire is redundant as is the black earth wire connected to the tag on the gear casing. In it's original role this earth tag was probably used as a piggy back for the parking earth wire emerging from the slip ring. Here the supply and earth are connected to the window switch which reverses the polarity to achieve raise/lower operation.

[John Larkin]

I noticed "POS GRD" stamped into the outside of the casing of one of my window motors. Upon further examination I found "NEG GRD" stamped in also at a position 180 degrees around the casing. In the attached photo the "POS GRD" stamp is beside the plastic boss through which the main power cables emerge from the body of the motor. On the other motor the stamp "NEG GRD" is in this location, with "POS GRD" 180 away.

The casing appears to be mountable on the motor base in either of two positions 180 degrees apart in rotation. Does this mean the the casing performs some sort of switching function to change the polarity, or is that a silly question?

My car is negative earth. Can anybody tell me which arrangemnt of motor casing is correct? Both motors work by the way.

John Larkin