Wiper Motor Control Circuit for 3 wire BMW wiper motors

[CMM3]

In getting ride of the wire harness and re-using the stock wiper motor it proved to be a challenge to get the motor to operate low & high and then shut off in the appropriate "park" position. A good friend of mine came to the rescue with this simply circuit made with two relays and a DPDT switch. After reading about other racers having to mess around to try and get the wipers to park by repeatedly turning a switch on off which is distracting and from what I've heard has actually caused a crash, thought I'd share this. Works like a charm.

[318 318]

Nice, doe this work with the E36, I have no idea if it has a 3 wire wiper motor, but mine only runs flat out and doesn't park automatically.

[CMM3]

I would think so the z3 shares a lot of parts with the e36 easy to check if the connector coming off the wiper motor has 4 wires total 3 thicker and one small then it should work

[Novablue454]

Posting for when I finally get around to wiring my wipers.

[CoMZ302]

Here's what I did:

http://www.bimmerforums.com/forum/sh...ighlight=wiper

It's basically the same as your diagram, without the relays.

EDIT: yours actually auto-parks, and offers high and low wipers.

So, yours is more complex, but better functionality.

Nice work.

[CMM3]

I'm not sure if your approach is switching the power feed to the motor but this is one of the things I like about the circuit my friend came up with. The power supplied to the motor is switched through the relays, which is a good thing and the DPDT switch is only switching the ground to the relays. Therefore all the wires I used going from the switch to the relays are small 22 ga. and the only heavier wire needed is to supply power to the relays. I used the stock wiring in going from the motor to the relays and from the motor to ground. I mounted the relays to a small piece of carbon fiber along with some terminal strips and made all the connections at the terminal strips and switch with spaded terminations on the wires and used sockets for the relays so I can replace any of the components easily without having to touch the wiring. I also used a push button reset circuit breaker instead of a fuse so I don't have to worry about carrying fuses around.

[EX27]

please reupload the photo. im doing the same thing and I'm stuck with wipers

[CMM3]

please reupload the photo. im doing the same thing and I'm stuck with wipers

BMW Wiper Control Circuit.jpg

Here it is

[jimmypet]

I did mine without replays I went the super simple way Chuck described in his 1st post.
Mine is a DP switch, up is fast, down is slow, Im switching power to the motor, motor is grounded, and I've had pretty good luck just stopping it out of my way if I wanted to.
The stopping out of the way is easier with a single wiper.
I dont stress over it, If i want to shut them off, I just wait for a straight away or other moment when I would otherwise have time to check my gauges and breath.
As the wiper moves to where I want it, I flick the switch off, its really not been an issue at all, not near the issue I was afraid it would be.

[aeronaut]

BMW Wiper Control Circuit.jpg

Here it is

If you want auto-park of wipes, why not just keep the original Wiper Control Module? It's lighter and and already wired up, compared to 2 relays, etc.

[BlackHawkRacing]

Gonna be that guy who bumps a 3 year old thread.

I am attempting to replicate the wiring diagram CMM3 posted, but have run into a potential issue given my wiring set up. I am running a Bussmann RTMR box that has all of the 86 pins for the the relays bussed to a single lug that provides power directly to those pins. In the diagram, it looks like the only purpose of having the 86 and the first 87 pin connected to the fuse is to provide power to the those items. If they are getting power independently, this set up should still work correct, yes?

Update: It works.