Quote:
Originally Posted by archwerks
xDrive50i;
do u mean that u just disengage the nav dvd by pushing the eject button on the dash but leave the disc partly sticking out?? & u get faster response on the rrview cam?
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If you leave the disc halfway in the drive, as soon as you 'power up the car' it will load the disc which puts you right back where you started. You need to take it out of the drive, THEN 'power up the car'. Every optical drive first needs to bring the disc up to speed (that can take anywhere from a second or two to a couple of seconds depending on the drive), then it needs to calibrate it's optics before it can be used (which can also take a few seconds and may even take longer in cold weather). The processor usually has to wait for the drive to finish it's boot up process (and may not do anything else depending on it's OS implementation). After the drives boot up process, the processor than has to load whatever it requires of the disc. In the case of the Navigation system, it first needs to acquire your current GPS location (again, this takes a second or two), then search for the corresponding data on the disc, load and process the map data before it can display it. These embedded processors usually have limited processing power and or memory and hence their ability to multitask is very limited. So when you put the car in reverse, the camera may be ready and has the video available, but the processor is still busy booting and loading or waiting on the optical drive or other systems within the cars network to complete their boot up/diagnostic sequence and indicate their readiness status. I have found that the optical drive is by far the worst culprit of them all taking the longest to boot and be available to the navigation/on-board computer.
Another contributing factor I found is if you put a CD into the CD drive that contains MP3s. The processor first has to load the directory structure, scan the disc for sub-folders and process it. This takes away processing power that would normally be available to the processor to handle other tasks. The same goes for USB connected devices, although the process is a bit faster due to the access speed difference between the CD drive and the USB interface. There is also a big difference between playing back a regular music CD and a CD containing MP3s or playing MP3s from a USB memory stick since the processor needs to decode/process the MP3s versus simply forwarding the regular audio data to the D/A converters.
Also, keep in mind that the quality of the discs (either the navigation DVD or music CD) plays an important role in how long it takes the drive to calibrate it's optics. This is especially true for recordable discs!
Give it a try, remove the navigation disc from the DVD drive BEFORE you start the car. I would also suggest you remove any music CDs (or MP3 CDs whatever the case may be) as well as any USB connected devices. Lock the car and wait a bit. Then try to open the car with your comfort access and enter the car as you usually do and start it up and see how long it takes for the camera to come up when you put the car in reverse.
Hope this helps you...
Post some feedback if you do end up trying it.