So The Frost is Here Where is the rear Window Defrost
#1
Junior Member
Thread Starter
So The Frost is Here Where is the rear Window Defrost
Morning all, so new to me 2010 S550 has a defrost issue apparently. First frost of year, start car click on switch for rear defrost and light on switch is on but seems rear window defrost does not do anything reclicked switch after its first 10 minutes same result nothing... some sort of magic I'm missing? Any help would be great.
#3
Out Of Control!!
Join Date: Jul 2003
Location: North Scottsdale, AZ
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'71 Pinto
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#6
Not up my 2010 if they made a change, but yeah the defroster is laughable. One of the first things I noticed as in a "Really?" moment.
Microscopic filaments in the back glass that do basically nothing compared to the big ones on you dad's Chevy.
Microscopic filaments in the back glass that do basically nothing compared to the big ones on you dad's Chevy.
#7
Member
Something is apparently wrong with yours. Mine works very effectively. Just a couple of minutes from frosty to clear.
Have you scanned for codes?
Have you scanned for codes?
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#8
Junior Member
Thread Starter
So ignored the terrible defrost till just this week, relay good (swapped from other MB) so has power just unbelievable how poor this system is saw no temp increase on window with laser thermometer, have now chased wires that connect to glass but don't want to blow a couple hundred for some MB Service writer to explain it works fine
#9
The rear defrost does work well on mine - however the service literature also points out that the illumination of the rear defrost light may be deceptive. Depending on ambient temperature, and main bust voltage, the system may not immediately activate the rear defrost even though the light is illuminated. What this magic formula is remains undocumented in the literature.
#10
MBWorld Fanatic!
The rear defrost does work well on mine - however the service literature also points out that the illumination of the rear defrost light may be deceptive. Depending on ambient temperature, and main bust voltage, the system may not immediately activate the rear defrost even though the light is illuminated. What this magic formula is remains undocumented in the literature.
#12
Junior Member
Thread Starter
The rear defrost does work well on mine - however the service literature also points out that the illumination of the rear defrost light may be deceptive. Depending on ambient temperature, and main bust voltage, the system may not immediately activate the rear defrost even though the light is illuminated. What this magic formula is remains undocumented in the literature.