This message is marked as Important.

Subject: Genuine BMW Rear View Camera Retrofit (Part 3) Author: farnarkler : member since February, 2004 : 1308 posts Posted on: 2006-10-20 01:38:37

I know I said that
Part 2
was the final post on the matter - but I have some more to tell you that may be of interest.
Basically, my camera works only when I pre-select the TV. That really won't change until I get a later TV module. But I still had the problem of activating the camera when I was driving. Something I needed to do to check on my trailer.

So I fitted a switch.

At first I wired this switch to take Pin 17 of the TV module to ground. This selects the signal from the reversing camera. But it didn't work. It seems that my camera module needed power not only from a 12 volt feed but also from the reversing light circuit. It was obvious that I needed to build a piece of OR logic to enable either the reversing camera or the cabin switch to turn the camera on. This is what I came up with:

It's a bit of a crappy photo but basically, when the "activate" line is at 12 volts the camera module gives out video and also pulls pin 17 on the TV module (where the flash bulb blob is) to ground.

I built my little OR gate with two diodes on a connector block:

and then put a piece of shrink wrap tubing around it to keep it from shorting out:


It's not pretty - but it works! I can now turn on the rear camera anytime I like. The only further work that may be need is to install a bleed resistor from the "activate" line to ground. I have noticed a protracted delay of around 10 seconds or so in switching off the camera which is probably due to high impedance on that line thanks to the diodes.

Hope it helps someone.

Farnarkler - '97 740iL Tow Hitch, UGDO, Always on TV, NAV, Tiptronic, Ultrasonic Alarm, 16 X 9 Display, Reversing Camera

• Genuine BMW Rear View Camera Retrofit (Part 3) (pic) (url) - farnarkler 2006-10-20 01:38:37 (11686 views)
  • Excellent switch location! I may copy you. - Brian 2006-10-20 06:47:53 (426 views)
    • Brian, that's so funny! I was thinking exactly the same thing. - sealbeach740 2006-10-20 12:39:52 (378 views)
      • The switch location is nice and stealth... love it... (nt) - mharv 2006-10-21 05:38:13 (389 views)