544 Wiper Info

First Published Apr2016, R. Kwas, updates on-going

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I have have never owned one of these fine vehicles, but thought it was time to collect what info I have been able to research and deduce on this page, to help my 544 owning friends. 

 

Wiper Systems installed on the 544 have less variations than those of the 122 and later models, but they are very different, as they use a Permanent Magnet Motor requiring Dynamic Braking.  This also makes them a bit more complex, to make things pretty interesting when servicing or troubleshooting.  Only single speed motors were ever fitted, (Reference:  Single Speed Wiper Motors) and although the four wires running between Switch and Motor Assy might suggest that a dual speed motor was installed...it wasn't!...and the electrically powered Windshield Wiper Pump shown on factory Wiring Diagram is quite rare. 
 


Picture of an SWF Wiper Motor Assembly.  Cover is held in place with a wire bale, and when removed, allows inspection/
replacement of Motor Brushes.  Gears and Park Switch mechanism is contained within die cast base of the assembly. 

 

The 544 Wiper Motor Assembly is a two stage Spur Gear design with Dynamic Braking.  It is a SWF (confirmed, or Bosch, this is not confirmed)  supplied unit, very similar to those fitted to Volkswagens of the era (Reference:  Thread at The Samba), or even SAABs.  The spur gear with Field Motor and Dynamic Braking design is quite different from later mechanisms fitted to 122s which had Field Motors and Worm Gear Mechanisms with no Dynamic Braking.  Later models after the 122 and early 1800s again had Permanent Magnet Motors requiring Dy Br (more on that in the Wiper Systems Tech Article:  Dynamic Braking).  Important point to note is that 122 Wiper Motors and mechanisms cannot be fitted in a 444/544, although through an odd sizing coincidence, the rear window wiper mechanism of a 245 apparently can be!  

Wipers for 12V sys are an Ignition Powered, Fuse 1 Circuit load, as the following Wiring Diagram excerpt shows.  Switch and Motor Assy are shown simplified in the factory manuals and without internal details.  Although four wires run between Switch and Motor, this does not mean Wiper Motor has two speeds.  It confirms that Motor is a PM type requiring Dy Br, and this is done with the Green wire.  This diagram also doesn't show the sequential nature of a multi-position pull-switch or Dynamic Braking contacts.  I will add further details on internal of switch and Motor Assy as I develop them. 

Excerpt of 12V Wiper System from 544 Wiring Diagrams showing Wipers and little detail (three Position Switch):   

 
 Extract from 12V 544 Wiring Diagram, showing Wiper related components and connections.  Four wires connect switch to Motor Assy to allow Dynamic Braking.  Electric Washer Pump version is shown, but this arrangement is rare. 

6v Wiper System looks similar to the 12V sys, but it is powered by Fuse 4 (Two Position Switch): 


Extract from 6V 544/210 Wiring Diagram , showing Wiper related components and connections.  Wire colors, terminals and connections between Switch and Motor Assy are similar to the 12V version, but wire gauge/cross-sectional area, is unsurprisingly double that of 12V sys.  Supply is also Ignition Power, but by way of Fuse 4 (...oh goody!...you get to have two 25A shorties!).  No electric Washer Motor is shown.  

Picture of SWF Assy, posted in a response by Eric H. on Brickboard thread:  https://www.brickboard.com/RWD/volvo/1630843/444-544/wiper_motor_wiring_q.html 
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After some research and input from experienced experts like Jack A. from the vintage SAAB world (...and we wont hold that against him!...they apparently also used a version of this Assy), the internal details become clear: 

 
From some SAAB manual (kindly provided by Jack A.) Switch shown in the OFF position.  Note closed 31 to 13b contact in this Switch position,
which routes chassis return path to Motor Assy (for Dy Br).  Note also, that Cam (3) which actuates Transfer Pin (4) and which operates the Dy Br contact,
 is shown in the mid-travel (not Park!) position, so terminals 53 and 53a are making contact and power would be routed to Motor to complete one wiping cycle.    

Incorporating this information gives this improved Wiring Diagram showing internal detail:  


Detailed 544 Wiper Wiring Diagram, contacts shown in the OFF and Parked condition 
(Terminal 53 is connected to 31b and Chassis by way of Wiper Switch.)  
Added Snubber Diode (green) found on later Motors*.

Snubber diode is effectively across the closing contact of "Parkswitch", and minimized its erosion. 


Switch position and function in original unchanged configuration: 

1.  OFF (Motor is powered by Park Switch and runs until Park Switch transfers to Dynamic Braking to aid Motor stopping).
2.  Wipe
3. 
Wipe Plus Washer Motor power

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Intermittent Wiper Control added.  It must be of the type having both a closing and an opening contact.  It cannot be the simple type having only a closing contact!  Understand, the author has spend significant effort considering the details of this, so this information will be forwarded only against an engineering charge.  Please contact SW-EM if interested in installing this feature. 

The 544 Wiper Motor design is a Permanent Magnet Motor with Dynamic Braking (unlike a 122 or 1800 which use Field Motors with no Dy Br)...this makes adding an Int Wip Cont more difficult, but not impossible, because with Dy Br, a chassis connection is made by way of the Wiper Switch in the OFF position, and this connection MUST be opened by Int Wip Cont when activated (otherwise there would be an inadvertent short to chassis on the incoming power).  This means that a typical Int Wip Cont with a simple closing contact is not suitable, but the Bosch 0 336 920 004 or Hella 5WA 001 871 04, which have separate closing and opening contacts, will play successfully with this system.  SW-EM does not supply these Int Wip Cont, customer must source these or a functional equivalent. 

Switch positions and function with Int Wip Cont wired: 

1.  OFF (If not in Park Position, Motor is powered by Park Switch and runs until Park Switch transfers from applying power, to Dynamic Braking and Motor stops.  After variable delay of Int Wip Cont, chassis connection is removed by opening contact, and closing contact applies power momentarily to Motor to move it away from Park position.  Park Switch then applies power to complete one cycle and Park it again.  Cycle repeats as long as Int Wip Cont is powered and cycling).
2.  Wipe (Normally, takes precedence even with Int Wip Cont powered and cycling in the background).
3.  Wipe Plus Washer Motor power.

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Service Note: 
The Motor Assy is difficult to remove from the Wiper mechanism while installed in vehicle!  It is simpler to remove the entire mechanism, then separate the Motor from the assembly. 

Installing a two-Speed Motor: 
Only single speed Motors were installed by Volvo (Reference:  Single Speed Wiper Motors), but I have one first hand account of a two speed Motor from a 140 being adapted and mounted on a 544 mechanism (Reference:  #Krarup_two_speed_140_wiper_motor_into_a_544).  An adapter mounting plate was necessary for the Motor Assy, shortening the bell-crank was necessary, and the Two-speed (plus Wash) Switch (Four Position?) obviously needed to come along also, but apparently it can be done!  The developer has sent pictures and details, and I have collected them in a separate page, linked at Reference.   

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Reference information: 

Spur Gears, from a popular reference source:  https://en.wikipedia.org/wiki/Gear#Spur

From the same popular reference source under Dynamic Braking:  "Dynamic braking can also be achieved by shorting the motor terminals, thus bringing the motor to a fast abrupt stop." 

Worm Gears, from the same popular reference source:  https://en.wikipedia.org/wiki/Gear#Worm

Only Single Speed Wiper Motors were ever fitted to the 544:  From Michael Krarup's posting:  https://www.brickboard.com/RWD/volvo/1631001/444-544/wiper_motor_wiring_q.html
"PV's never had two speed wipermotors, this was one of the reasons why the last 69 Duetts were sold as 68 models, because the law in Sweden was changed per January 1st 69 that all cars had to have two speed wipers."

Michael Krarup has also adapted a Two-Speed 140 Motor Assy into a 544!  I have collected all of this info here (republished with his kind permission), and he has also OK'd being contacted about it at the e-mail given, reader will have to correct his e-mail in the usual manner.

From our VW friends at the Samba:  http://www.thesamba.com/vw/forum/viewtopic.php?t=508707&view=next 
"The single speed wiring shows a turning switch and Park Switch I expect would be similar to the Volvo application."

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Links:  

Sw-Em Technical Article:  Windshield Wiper Systems

Thread from our VW driving friends at the Samba:  64 Wiper motor 6v to 12v build    http://www.thesamba.com/vw/forum/viewtopic.php?t=389208

Jack Ashcraft, of the SAAB world looks at an SWF Wiper Motor Assy:  http://saabjournal.blogspot.com/2015/01/volvo-544-windshield-wiper-motor-rebuild.html 

More here:  http://www.thesamba.com/vw/forum/viewtopic.php?t=509371

Brickboard Thread:  https://www.brickboard.com/RWD/volvo/1581428/444-544/wiper_motor_issues.html

In scanning for Intermittent Wiper Controls, the inexpensive Velleman K2599 kit would be suitable.  Delay timing is steps and not continuously variable.  It is a simple kit without an enclosure, but has the requisite opening and closing contacts required (actually two independent relays controlled by the same timer).   See:  http://www.velleman.eu/products/view/?id=9019   Internal Wiring Diagram at:  http://www.velleman.eu/images/tmp/K2599DIA.jpg

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Very good info from a Charles Greenlaw post on an older Brickboard Thread:  https://www.brickboard.com/RWD/volvo/690885/444-544/544_wiper_wiring_problem.html


 

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External material sources are attributed.  Otherwise, this article is Copyright © 2016-2017.  Ronald Kwas.   The terms Volvo, VW, Bosch, SWF and Velleman are used for reference only.  I have no affiliation with any of these companies other than to try to keep their products working for me, help other enthusiasts do the same, and also present my highly opinionated results of the use of their products here.  The information presented comes from my own experience and carefully considered opinion, and can be used (or not!), or ridiculed and laughed at, or worshipped, at the readers discretion.  As with any recipe, your results may vary, and you are, and will always be, in charge of your own knuckles, and future! 

You are welcome to use the information here in good health, and for your own non-commercial purposes, but if you reprint or otherwise republish this article, you must give credit to the author or link back to the SwEm site as the source.  If you donít, youíre just a lazy, scum sucking plagiarist, and the Boston Globe wants you!  As always, if you can supply corrections, or additional objective information or experience, I will always consider it, and consider working it into the next revision of this article...along with likely the odd metaphor and probably wise-a** comment. 

 

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