Where in the world, aside from a stroke of luck at the pick and pull, could I find a non-sandblasted, good condition W114/115 rear window with working defogger elements?
Does such an animal even exist anymore?

Phil Forrest

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1972 220D "Trudy," named by a friend.

"The 220D sounds good... I suspect it is the only car that you need a calendar for, rather than a stopwatch, when doing acceleration tests."
Tom Abrahamsson

good luck, I know where there is a good condition rear widow in a 76 300D
at a pick and pull in Oregon by where is live, defroster condition???

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MAKDUFF3

1975 300D, Feuerrot and Parchment interior

1971 220D (RIP)

I've got a friend in Vancouver, WA who could check it out and pull it for me if it's in the greater Portland area.
I'm going to check the P&Ps in the Albuquerque area this week to see if i can score one. W114/115 cars seem really uncommon around here though.

Phil Forrest

__________________
1972 220D "Trudy," named by a friend.

"The 220D sounds good... I suspect it is the only car that you need a calendar for, rather than a stopwatch, when doing acceleration tests."
Tom Abrahamsson

Shipping a windshield is a pain in the ass and quite prone to breakage.
Finding one is easy in Los Angeles. Testing the defroster? What do you do, measure the resistance between the terminals on the sides?

I'm not sure how much resistance each grid line needs to work in the W115/114 chassis but since all of the grid lines are connected through the strips at the sides, putting an ohmmeter against the lines wouldn't necessarily work. I'm not sure how to really test them individually.
My 220D was stored for over a decade in California and Pennsylvania then the previous owner cleaned the rear window and scraped off the grid almost completely. I have half a mind to delicately scrape off the adhesive lines then make it completely clear and just deal with the frost like I used to on my old VW beetle. With an ice scraper and the car's heater. The problem is that I don't live in an area where daily use of the defogger isn't necessary.

Phil Forrest

__________________
1972 220D "Trudy," named by a friend.

"The 220D sounds good... I suspect it is the only car that you need a calendar for, rather than a stopwatch, when doing acceleration tests."
Tom Abrahamsson

I don't think you can test the individual lines. I thought you could test the end points as a whole to see if there is a measurable resistance. That won't tell you which lines work and which don't. But it should tell you something.

The correct term for testing a rear window grid is to test for Brilliance. In reality you are testing it like you would any other wire, but in the early days of window grids, like the late 60's, the term Brilliance was introduced and is still used by some.

Using this term in a Google search will return a number of sites.

But this video is a good place to start. You can use any voltmeter for this; a Fluke is not necessary but it is an easy instrument to work with.

How to use a Fluke 233 to test a rear window defroster - YouTube

It's still very difficult to test for breaks in the grid since no matter which line one is testing there are always other parallel circuits which could give a false reading.
Aside from a brand new grid or installing a window and testing it on a moist cool day, I don't know of a way that I could test the grid at the pick and pull before taking the rear glass out.

Phil Forrest

__________________
1972 220D "Trudy," named by a friend.

"The 220D sounds good... I suspect it is the only car that you need a calendar for, rather than a stopwatch, when doing acceleration tests."
Tom Abrahamsson

it is at this place,


Classics U-Pull It U-Savemore info‎
30545 Southeast Compton Road
Boring, OR 97009
(503) 663-2211
boringauto.com‎

__________________
MAKDUFF3

1975 300D, Feuerrot and Parchment interior

1971 220D (RIP)

I have some in SLC UT. condition of defroster UK. They have articles on how to repair them if googled?

My rear window grid can't be repaired, since it has all been scraped off.

The problem with a window with defogger grid of unknown condition is that the only real way to test it is to install it and wait for a day where condensation and/or frost exist.

The Permatex repair kit barely works as well. I repaired my grid in my '78 300D and only gained function in two more of the elements out of the dozen or so that are in the window.
Yes, I did it according to the instructions.

My only sure-fire option may be to get the window from Mercedes Benz, in which case, I'll live without the defogger grid. Either that or find a car that has a known working grid and take that window (if it's available.)

After my two-day ordeal with that rear window seal, the next time I install a seal, I'm going to have a guaranteed working window defogger because I don't want to do that again in the next decade.

Phil Forrest

__________________
1972 220D "Trudy," named by a friend.

"The 220D sounds good... I suspect it is the only car that you need a calendar for, rather than a stopwatch, when doing acceleration tests."
Tom Abrahamsson