Parking Sensors

I'm not quite clear how an electromagnetic type would sense a brick wall?

Could be EM as in RADAR I suppose.

Always wanted to fit a radar module into the front of my car, complete with hookup to the wheel sensor, so I could make a "you're getting too close" alarm for me.

Not because I drive too close, just for the hell of it! (I once modified an ultrasonic tape measure & hooked it up to a PC for a science fair, to make a "measure your height device". Sad I know!)

Pete.

The message from "Ian" contains these words:

I imagine the electromagnetic ones won't detect Reliants! Or tree come to think of it. Or wooden posts in car parks. Or kids.

The message from Pete Smith contains these words:

Crank the power up enough and you could just fry the bastards.

Are these parking sensors acceptable in a driving test examination?

I looked at all the info and decided the em type is best, the ultrasonics don't always work, especially if grubby, also they cannot detect someone lying behind the car. Look on american sites for better info, the kill some horrendous figure every year by backing over them. I have bought some em units for my nice car, but haven't had time to fit them. I have fitted ulrasonics for other people several times and not been impressed, one of the problems is that they don't warn for less than a foot (distance), if you are in a tight spot you want to know down to about three inches or less would be nice. The em ones claim 4 inchs.

mrcheerful

The message from "dave F" contains these words:

I don't suppose there's anything wrong with having 'em or possibly even using 'em but I can guarantee that you'll still be expected to make adequate all round visual observation throughout the manoeuvre.

Why not use the method employed by OAPs in car parks, wait for the crunch / bang / thud etc.

Your eyes and some sort of spatial awareness.

My current car (secondhand) came fitted with PDC at the rear. I'd never have dreamed of specifying/paying for it, and thought like you. But having lived with it for a few years, I wouldn't now be without it. I fitted an aftermarket set to the SD1 which probably needs it more than any other car I've driven. (When they came out, they had a stainless steel bumper, and you hardly ever saw an undamaged one. Series two cars are black painted fibreglass)

You'll fail a test if you rely on them at all.

The message from Conor contains these words:

Wasn't that near enough what I said?

The impression I got from your post was that you could use them inconjunction with all round checks.

The message from Conor contains these words:

Quite. But not rely on them. If you've an extra source of information I don't believe the examiner would fail you for using it, provided you weren't relying on 'em.