Courtesy Light Assembly 122/544 Notes
Dec 2023  R. Kwas  (Updates on-going!)  [Comments Added!]

544 (6V) Courtesy Light
140 Courtesy Light

Courtesy Light 1800 Information and Notes

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The courtesy Light in 122 (also 544) vehicles is a simple arrangement located in the front and center roof area between driver and passenger.  It features a three-way switch with the positions:  Door-OFF-ON. 

A ~3mm chromed ball, held into three depressions by a spring in the pivoting Handlever, provides the mechanical detented positions as well as the electrical contact necessary for function.  A weakness in this implementation is that after many years, if left unlubricated, the mechanism gets gritty and sloppy and the fact that the Ball has no lube, allows the Ball to pop out of place, resulting in loss of the mechanical detent and the Handlever feeling floppy, and no electrical contact.  Complete non-function results......


122/544 Courtesy Light assembly with snap-on Lens.  [...phonecam seems to have played with color-temp of lighting...]

 


Detail of Courtesy Light Switch as found...exhibiting pretty a crusty (originally) chromed (but not anymore!) Detent Ball.  The Handlever is actually metal on this example, leading me to believe this assembly, sourced from the SWedish-EMbassy Random Used and Abused Parts Hoard (SW-EM RUaAPH) is originally from a 544...those of the 122 however, are substantially similar, with the Handlever being of plastic. 

 

The wire terminations and pivots get a drop of Tri-Flow!


Lubed, awaiting reawakening!

After only 2 minutes of soaking, and with the use of a needle-nose pliers on the metal Handlever to help with the leverage  [DO NOT try this on the plastic Handlever of the 122 version!!], the Switch is persuaded to budge through the three positions...

 

Conical Contact ends of original lamp (41mm X 10W "Festoon" [...what ever that is!?!]) are cleaned, anointed with a dab of ACZP, and reinstalled into a cleaned holder. 

 

Power-up Test: 


Supplied with bench power, the Ball-Detent/Elec-Contact has the desired effect, even grody as it is! 

The assembly in this condition is not quite ready for prime time! ...a lot more clean-up would clearly be in order, but the reader should hopefully get all the important and necessary information here, with which to return their intermittent or entirely non-functioning 122 Courtesy Light to reliable service!  
 

Wiring Diagram Detail Excerpt:  

The Glove Compartment Light is on the same Fuse4 Load circuit as the Courtesy Light, so it is included here for completeness: 


Excerpt of 122 Wiring Diagram showing supply of power to Fuse4, and downstream protected circuit. 
 

[A quick look at the (12V) 544 Wiring Diagram shows only one Door Contact, but the Courtesy Light is still supplied by Fuse4!]

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My Response to a question about a non-working Courtesy Light in an Amazon (info would be directly applicable to a 544 also!)

"Courtesy Light in an Amazon is supplied by Fuse4! If it's not blown and simply spinning it restores function, see:  https://www.sw-em.com/anti_corrosive_paste.htm#ACZP_on_Eurofuse_ends

...if that still doesn't restore function (even in the Always-ON position), remove Lens (carefully, they are brittle, and may have caught the little 3mm ball bearing I speak of next!), and check to to see if the little Ball Detent/Contact of the Switch has not become dislodged and fallen out of place, resulting in no contact [...and the Handlever being floppy and without detents!]. If the later is the condition, replace the BD,with a little lube so it rolls better on the contact and doesn't instead fall out of position again. Good Hunting! "

 

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544 (6V) Courtesy Light: 

Courtesy Light is supplied by Fuse6, and note that there is only one door switch, located on the driver's side.  There is no door switch on the Passenger's side!

 

Here we see a 544 CL with a plastic Handlever, so the plastic vs. metal Handlever seems not to be a function of model, but the fact that they were supplied by different manufacturers. 

 

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140 Courtesy Light: 

While the Lens is a "more modern" square design, the works below [...or above depending on your point of view!] have a similar design of the Switch, but with the ball doing the duty of a mechanical detent only.  The electrical duties are performed by a separate formed copper contact, but the BD can still use a dab of light grease to keep the action smooth! 

Zoltán Makovsky pictures, permission requested.

 


Ball Detent, Electrical Contact  

 

The side seldom seen when installed in a car! 

 

This style was also fitted to the 1800ES models since the B-Pillars are of a much smaller design than those of the non-wagon body-style. 

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Links: 

The Courtesy Lights of the 1800 models are of a different design, located on the B Pillars, and covered separately here: Courtesy Light 1800 Information and Notes

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Reference Information:

 

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External material sources are attributed.  Otherwise, this article is Copyright © 2023.  Ronald Kwas.  The term Volvo, is used for reference only.  I have no affiliation with this company other than to present my experience, and highly opinionated results of the use and care of their products, for the purpose of helping other owners keep their vehicles on the road, safe and reliable.  ...and I sure as hell don't have any relationship with Lucas, except to give the all the grief they so fully deserve (see for instance:  Proving Everything Bad you Ever Heard About Lucas).  The information presented is my own, 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 Sw-Em site as the source.  If you don’t, you’re just a lazy, scum sucking plagiarist…so 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 maybe wise-a** comment. 

 

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