XPost: alt.home.repair, sci.electronics.repair   
   From: rod.speed.aaa@gmail.com   
      
   On Thu, 19 Jan 2023 02:16:22 +1100, Peter   
    wrote:   
      
   > MightyWannabe wrote:   
   >   
   >> There is a good possibility the rectifiers (diodes) in your alternator   
   >> could fry because it is recommended that your car be running when you   
   >> jump start another car. The rectifiers of your car is supplying electric   
   >> current from the alternator and can overload due to the jump start   
   >> operation.   
   >   
   > In the recipient car, when the engine finally starts, I was told since I   
   > was young that the best way to "absorb" some of the excess current in the   
   > first few seconds is for the recipient to turn on the headlights.   
   >   
   > This seems counterintuitive from the recipient's standpoint in terms of   
   > "using" current but the theory is that the "B" sense circuit of the   
   > alternator (which is just a coil of wire in the end) senses a "very low"   
   > battery so it tells the alternator to put out a "very high" current,   
   > whose   
   > initial burst could ("they say") fry the rectifying wheatstone diodes.   
      
   That makes no sense because it would happen with any very   
   poor battery which does eventually manage to start the engine.   
      
   > Maybe it makes sense to the electronics folks   
      
   Nope.   
      
   > who are asked to comment.   
      
   >> There is also the possibility of the voltage drop so low momentarily   
   >> that your car stereo's anti-theft system kicks in, and you'll have to go   
   >> back to the car dealership to enter the anti-theft code. The anti-theft   
   >> system detects the zero voltage when it is ripped from the dashboard.   
   >   
   > But what happens each time you replace the battery every few years?   
      
   The best way to change batterys is to keep supplying 12V with the original   
   battery removed until the new battery has been connected. Thats what the   
   pros do to avoid the antitheft system kicking in.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)