michael1972 Posted December 20, 2014 Report Share Posted December 20, 2014 WTF would cause this? I was sitting in my car this morning warming it up rear defroster was on. I hear a loud bang. Thought the car backfired. Go to back out the driveway and glass falls into the car from the rear window. Whole thing spiderwebbed. Quote Link to comment Share on other sites More sharing options...
ClassE Posted December 20, 2014 Report Share Posted December 20, 2014 I've heard if that before - I think the defrost button sticks on and the rear defrost keeps going until the heat difference cracks the glass?!?That really sucks tho! Quote Link to comment Share on other sites More sharing options...
Boris3 Posted December 20, 2014 Report Share Posted December 20, 2014 That's not good. Glad no one was sitting in the rear!Switch issue or replacement window install issue:http://www.bimmerforums.com/forum/showthread.php?1731572-Rear-Defroster-breaking-rear-window Quote Link to comment Share on other sites More sharing options...
jc43089 Posted December 20, 2014 Report Share Posted December 20, 2014 It is angry at being winter driven lol. Sent from my potato phone Chris Welter 1 Quote Link to comment Share on other sites More sharing options...
michael1972 Posted December 20, 2014 Author Report Share Posted December 20, 2014 Well I was supposed to get it replaced tomorrow at safelite but they screwed up and don't actually have the glass in the warehouse that the computer said they did. So now it should be Tuesday. Quote Link to comment Share on other sites More sharing options...
GB-335xiCoupe Posted December 20, 2014 Report Share Posted December 20, 2014 Well I was supposed to get it replaced tomorrow at safelite but they screwed up and don't actually have the glass in the warehouse that the computer said they did. So now it should be Tuesday.Bastages. Quote Link to comment Share on other sites More sharing options...
michael1972 Posted December 24, 2014 Author Report Share Posted December 24, 2014 Just a pic of my blow out. New glass is finally in. We'll see how it goes. Quote Link to comment Share on other sites More sharing options...
YoungCR Posted December 24, 2014 Report Share Posted December 24, 2014 that seems really odd to me being just a section that went out. You would think if it was heat related it would have spread all the way across. Quote Link to comment Share on other sites More sharing options...
B C Posted December 24, 2014 Report Share Posted December 24, 2014 There was probably a high resistance spot in one of the lines that became extra hot Quote Link to comment Share on other sites More sharing options...
patsbimmer1 Posted December 24, 2014 Report Share Posted December 24, 2014 that seems really odd to me being just a section that went out. You would think if it was heat related it would have spread all the way across. It looks like it shattered the entire window just coincidence that that exact chunk crumbled. YoungCR 1 Quote Link to comment Share on other sites More sharing options...
jc43089 Posted December 24, 2014 Report Share Posted December 24, 2014 There was probably a high resistance spot in one of the lines that became extra hot You mean low resistance? Not sure how that would happen when they are already just a thin wire. Sent from my potato phone Quote Link to comment Share on other sites More sharing options...
michael1972 Posted December 25, 2014 Author Report Share Posted December 25, 2014 Yea the whole widow spiderwebbed. I'm not saying it was or wasn't defrost related but the glass guy said he has seen it happen on other vehicles from the defroster causing a hot spot. So strange. It popped loud as hell. Quote Link to comment Share on other sites More sharing options...
B C Posted December 25, 2014 Report Share Posted December 25, 2014 You mean low resistance? Not sure how that would happen when they are already just a thin wire. Sent from my potato phone If the grid is wired in parallel then voltage is constant through the circuit but current is the independent variable. Ohm's law V=I*R Would say that you are right and that resistance would have to drop for current to increase for a given voltage. SO im thinking some of the lines no longer had a complete circuit/were bad and the remaining lines had to carry more current which caused the hot spot Quote Link to comment Share on other sites More sharing options...
jc43089 Posted December 26, 2014 Report Share Posted December 26, 2014 If the grid is wired in parallel then voltage is constant through the circuit but current is the independent variable. Ohm's law V=I*R Would say that you are right and that resistance would have to drop for current to increase for a given voltage. SO im thinking some of the lines no longer had a complete circuit/were bad and the remaining lines had to carry more current which caused the hot spot But if resistance remains the same on the individual wires (how would it decrease) then overall resistance increases when one or more breaks. Ohm's lawed like a boss. 1/(1/r1+1/r2 etc) formula might not be right, lots of eggnog with brandy today... Sent from my potato phone Quote Link to comment Share on other sites More sharing options...
B C Posted December 26, 2014 Report Share Posted December 26, 2014 So what REALLY happened is Mike chucked a mini-sledge through the window to attempt insurance fraud. i cant electrical maths F*** electrons I'll use an ice scraper faja92 and jc43089 2 Quote Link to comment Share on other sites More sharing options...
Boris3 Posted December 26, 2014 Report Share Posted December 26, 2014 I'm with Snap, though wondering about the mini-sledge scenario? Given the hole I'd start checking for shotgun pellets...have any irate neighbors, ex-s, etc. B C 1 Quote Link to comment Share on other sites More sharing options...
B C Posted December 26, 2014 Report Share Posted December 26, 2014 Or electrons that spilled out all over the back seat Quote Link to comment Share on other sites More sharing options...
GB-335xiCoupe Posted December 26, 2014 Report Share Posted December 26, 2014 Flashbacks to Pulp Fiction where Vince shoots Marvin on accident.www.youtube.com/watch?v=LBBni_-tMNs patsbimmer1 1 Quote Link to comment Share on other sites More sharing options...
patsbimmer1 Posted December 26, 2014 Report Share Posted December 26, 2014 Flashbacks to Pulp Fiction where Vince shoots Marvin on accident.www.youtube.com/watch?v=LBBni_-tMNsPulp Fiction has some of my all time favorite movie scenes! Good choice! Quote Link to comment Share on other sites More sharing options...
michael1972 Posted December 26, 2014 Author Report Share Posted December 26, 2014 No mini sledge I swear Quote Link to comment Share on other sites More sharing options...
andyhundley Posted December 28, 2014 Report Share Posted December 28, 2014 This exact same scenic happened to me in my e30 about 4 years ago. I got a new rear window and installed it myself. It took me a few hours to do but it wasn't very difficult. Used silicone spray and my Wisconsin I.D. Quote Link to comment Share on other sites More sharing options...
andyhundley Posted December 28, 2014 Report Share Posted December 28, 2014 Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
DevianceInDark Posted December 30, 2014 Report Share Posted December 30, 2014 Damn I'm disconnecting my rear defrost! That's crazy. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.