Wiper electrics 1971-1973

[pehlivanov_tii]

I am trying to get my wipers to work correctly. This is the reassembly stage so I haven’t seen them working correctly from my side.

The car is 07/1973 tii, one of the last roundies. What is confirmed so far:

1. Motor is refurbished

2. The relay was bad and it was changed with working (tested) original 6-pin relay. 
3. I rang the wires to test them for broken ones and they are ok

4. I checked the fuse it is ok, contacts are cleaned, checked also with spare fuse - no issues there

5. The 2-speed switch on the dash is working good too.

6. Wiper/turn signal stalk is suspected, but it was cleaned from inside and lubed with electrical grease, wires are resoldered.

 

The problems:

Wipers don’t work (ignition is on), i am pulling the stalk, pushing that side button and nothing happens. 
My stalk is bought second hand and it seems to be the correct type for 71-73 cars, at least visually and comparing the wiring colors, everything matches.

But the disassembled wiring harness came with another stalk which is different type. This wiper stalk is broken. In the attached photo the stalk on the left is the good one that i bought additionally. The one on the right is the broken one which came with the car. The broken one that came with the car has the correct 71-73  plug and wire colors, but it is different, the type looks to me a little bit like the late type? On the second photo is the broken one again and its part number.

 

The odd thing is that when i connect the broken stalk and connect with hand the plates that connect the wires for the wiper, the wiper motor starts, but it doesn’t stop?

With the non-broken stalk nothing happens. 
=================

problem #1: why is my stalk not working

problem #2: when i manage to run the motor with my mystery broken stalk the motor doesn’t stop. What makes the motor to stop / turn the direction?

 

 

P.S. if that mystery broken stalk that i have is original it is very strange. Because wiper stalks with this number 1357008 that i have seen in ads are stalks with the same wire colors, but with late style plug. Since my last car is very close to the square tail lights era is it possible the car to was out of the factory with late style stalk, but with early style plug?
 

thank you guys

Edited May 15, 2023 by pehlivanov_tii

[Mike Self]

Those wiper assemblies are way more complicated then they really need to be...

 

A couple of thoughts:  with your broken switch, I think the wipers won't stop because there are actually two circuits supplying current to the motor.  When you turn the switch on, you're supplying current directly to the motor.  When you turn it off, another circuit supplies power to the motor through the contacts in the little round can that's attached to the motor.  Inside that can are two brass rings, each with a contact riding on the ring.  One ring is interrupted by an insulating strip; when its contact reaches the insulated section, current is cut to the motor and the wipers stop.  That's how they manage to (hopefully) park at the bottom of the windshield after you turn the switch off.  If that is your problem, PM me for a column I did on troubleshooting that glitch.  

 

As for the switch:  I did another column on troubleshooting those '72-73 switches.  They're probematical, primarily due to the two tiny wires that lead from the wiper switch down the stalk--and flex every time you use the turn signal...And eventually break.  But to check the switch itself, with it disconnected or at least with the ignition off, put an ohmmeter across terminals W and 15, and then press the wiper on/off switch several times to see if you have continuity (0 ohms) when the switch is on.  If you want to delve further, I'll send you the column.

 

And if John doesn't reply with one of his wiring diagrams, I have that too.

 

mike

[pehlivanov_tii]

Hi Mike, 

thank you! Could you please send me both troubleshootings, i will probably need them.

 

As for the stalk i tested it with multimeter. When i pull the switch toward me i get connection only between these two points on the photos, this is when both plates are contacting. When i push the side button nothing happens and nothing rings. I didn’t see which are W and 15, i think 15 is the purple black wire and W should be the black one?

[Mike Self]

According to my diagram, the two wires at the wiper/turn signal stalk that control the wiper on/off switch on the stalk end are black, and black with a brown tracer.

mike

[pehlivanov_tii]

Tried to ring both contacts with the ohmmeter, nothing happened. I tried with pulling the switch, pushing the button, but nothing.

[jgerock]

Push the end of the stalk inward to turn wipers on/off.  

 

Pull the stalk towards you to activate the windshield washer pump and wipers.

 

Dash knob controls the wiper speeds.

 

As mentioned above, if the two wires going from the base of the stalk to the tip switch are broken, the wipers will not work. This is a common problem. Looks like a  Black wire and black/violet wire. This is the switch in my 73tii.

[pehlivanov_tii]

Thank you guys, i tried that and nothing happened. I resoldered the wires, but it doesn’t work. Probably i should try with another stalk

[pehlivanov_tii]

I tried with another stalk and the wipe function (push button in the end) works fine. However there are still two issues:

1. The motor doesn't park. I know the common issues, i checked them and it still doesn't park. What i tried:

- removed the tuna can cover and cleaned the tracks from the old grease

- i made sure that the contacts are touching the tracks, i literally see how the contacts from the cover are touching the tracks before i put the screws of the cover. I even bent the contacts a little bit down so they are making contact for sure

- i tested the continuity of the contacts (the end points which are contacting the tracks) with the multimeter - there is contact between the 5-pin plug of the motor and the end contacts which contact the motor tracks.

 

So what could be wrong with this thing?

 

2. The next issue is activating the washer pump with the new and old stalk. It doesn't activate with both stalks, so i will have to check the wires too. The washer pump is new.

 

@Mike Self do you have any suggestions? Thanks!

[jgerock]

You don’t want to spend this kind of money….but Maximillian recently advertised NOS wiper motors (both early and later versions).

 

BMW '02 Wiper Motors! | MIC

WWW.MAX2002STORE.COM

---

New old stock Genuine BMW wiper motors for early and late versions. We are getting these from Germany in a couple weeks. There are only two wiper motors used on 2002's: a three wire motor (early version) and a five wire (late version)...

 

[pehlivanov_tii]

Yes, i saw that, but i wanted to make sure that the problem is in the motor before at least start consider it. Anyways, thanks for sharing it @jgerock

 

I spent some additional time with the multimeter and the motor and i start to think there is some mess with the wiring.

So when you open the tuna can, there are three tracks for the three contacts.

 

Contact 1 - is the contact with the widest diameter / perimeter. There is white plastic section so the power for this contact should stop when the contact touches the plastic section. What i concluded for this contact:

- it is hot all the time when the ignition is on (even with wiper stalk turned off)

- it makes continuity with black wire from the plug

 

Contact 2 - it is the mid motor track which  is all metal and there is no plastic section (like it should be hot all the time). What i concluded about this one:

- it is hot only when the wiper stalk is on, which is the strange part because when you turn the wiper stalk it is powering a track without park plastic section

- it makes continuity with black-yellow wire (the black wire doesn’t have yellow stripe, but yellow dots???)

 

Contact 3 - it is the contact that works with the smallest diameter track (that track also has a plastic park section if i recall). What i concluded about this one:

- it is never hot. I tried also to activate the wash function but again nothing happens, there is no power on it. As i said the wash function also doesn’t work

- it makes continuity with brown-red wire on the plug. 
 

Do you have any thoughts, guys?

I think it is strange that when the wiper stalk is one it is sending power to motor track without park / plastic section and it sounds to me like messed wiring, but how this could be messed?

Edited June 4, 2023 by pehlivanov_tii

[TobyB]

So it kinda sounds like you don't have a ground somewhere.

 

The 'park' circuit, in addition  to cutting power also grounds* the motor

to brake it.  Without this, inertia keeps the motor spinning long enough to

overrun the small 'park' gap and make another swipe.

 

So the contacts in the gearbox go from supplying power to run the motor

to grounding it in the 'park' window to stop it from spinning.

 

t

*it's been so long... I'm pretty sure the wiper provides ground, 

but I forget if it switches ground or positive, so there may, instead, 

be a supply missing.  You'll see on your particular wiring diagram.

I've worked on lots of different make wipers since the 02...