K40 in E53 issue
 

After doing some digging on a issue with my K40 that was installed when i purchased my x5 used I came across the solution to my issue..... Constant beeping when turned on. I have read that this is caused by a faulty rear sensor... question is I can't locate this rear sensor... any ideas on where it is typically mounted/solutions to this issue for those that may have a K40 on their vehicles? Thanks in advance guys.

-D

The K40 is an archaic device. If I were you, I'd actually remove the entire unit and replace it with a Valentine 1. I digress.

To answer your question, the K40 radar system consists of two sensors (one front and one rear) USUALLY mounted somewhere BEHIND the front/rear bumpers (likely mounted on the bumper support bar itself). You can't miss the boxes - they are black and are slightly larger than a pack of cigarettes.

In short, you will likely have to remove your bumper to locate the rig(s).

Note: The position of the radar sensors is what really hurts the K40 system - not only do the sensors have to sense THROUGH the bumper, they are also mounted very low.

Good luck.

I agree with Bayerische, I didn't know they were still in business...lol!! Go with Valentine 1 or Passport.

V1... you already chose BMW, why go less in radar choice?...

p.s. guys, have your rides' description in the sig line - helps to know who is driving what, and what advice should be given based on the ride...

Had a K40 stealth many moons ago...around when they first released the option to lower/increase volume. Worked great at the time till lasers became more common. They're still in business and have upgraded their systems, although perhaps not as effective as some competitors.

To answer your question, i believe the beeping, if your model is as old as i'm assuming, may be normal scanning operation. There may be two dials, one to power the system that also adjusts sensitivity for hwy/city settings (larger dial) and another dial to control volume (smaller/skinny dial).

Mounting locations can be tricky, you may have to get her up on a lift and take your time. It's also possible that the rear sensor may be missing.