I see the choices seem to be
1) use the rear camera if you have one fitted
2) use ultrasonic sensors which means drilling your bumpers, and also colour coding them
3) electromagnetic sensors glued to inside rear of bumper

Looking at the electromagnetic sensors, the basic unit readily available is the Parking Dynamics PD1 which retail around £80.
On Ebay there are similar units - ebuyer43 has something similar for around £25 whose only difference appears to be a smaller control box...these are the u301 model from China
[url="http://www.tradeeasy.com/supplier/34607/products/p974483/electromagnetic-parking-sensor.html"]http://www.tradeeasy.com/supplier/34607/pr...ing-sensor.html[/url]

Anyone fitted one of these and is there any interference with the can-bus system when the electromagentic field activates?

As an aside, has anyone got any pictures of the OEM/factory-fitted rear parking sensors in situ on a new Prius?

I'm considering spec-ing them on a T4, if they're not too objectionable aesthetically.

[quote name='Seamaster73' post='968829' date='Feb 5 2010, 05:57 PM']As an aside, has anyone got any pictures of the OEM/factory-fitted rear parking sensors in situ on a new Prius?

I'm considering spec-ing them on a T4, if they're not too objectionable aesthetically.[/quote]

I don't think you can get them factory fitted. They are listed as an accessory and fitted by the dealer as far as I am aware. Fit and finish are therefore going to depend upon the dealer.

I'll be happy to take a picture of mine if no-one has a pic available.

[quote name='Sagitar' post='968844' date='Feb 5 2010, 06:23 PM']I don't think you can get them factory fitted. They are listed as an accessory and fitted by the dealer as far as I am aware. Fit and finish are therefore going to depend upon the dealer. I'll be happy to take a picture of mine if no-one has a pic available.[/quote]

Ah, thank you, good info. They are listed as part of the "Protection Pack" (ie reverse sensors and boot liner) in the brochure.

Yes, I'd like to see a picture if it's no trouble.

[quote name='Seamaster73' post='968877' date='Feb 5 2010, 07:39 PM']They are listed as part of the "Protection Pack" (ie reverse sensors and boot liner) in the brochure.[/quote]

Yes, I was fooled by that when I ordered. The Protection Pack is actually no more than the "Toyota Parking Aid, rear 4-sensor system" together with the "Boot liner", both of which are listed on the Accessories page of the same brochure.

I am not sure whether you get a better price if you take both, but it might be worth asking if you don't really want both.

I'll produce a pic in the morning.

Post deleted

[quote name='Seamaster73' post='968829' date='Feb 5 2010, 05:57 PM']As an aside, has anyone got any pictures of the OEM/factory-fitted rear parking sensors in situ on a new Prius?[/quote]
I could take a picture......but I dare not because of all the motorway filth and muck the back of the car has picked up this week.
Out with the wash buckets tomorrow!

[quote name='Seamaster73' post='968829' date='Feb 5 2010, 05:57 PM']I'm considering spec-ing them on a T4, if they're not too objectionable aesthetically.[/quote]
Personally I think they look very well blended in and you have to actively look for them
Unlike some aftermarket sensors that really jump out at you.

Picture as promised.

[img]http://myweb.tiscali.co.uk/sagitar/Images/20100206Sensors.jpg[/img]

It's a filthy morning here so I left the car in the garage and just lifted the door to take the photo. I hope it will serve?

Do the ultrasonic sensors work well when they get dirty, or do they need to be kept pretty clean?
I guess people disable the standard reversing beeping so they can hear the sensor beep?..or is there enough difference in speed and pitch to hear both?

[quote name='cootuk' post='969066' date='Feb 6 2010, 11:22 AM']Do the ultrasonic sensors work well when they get dirty, or do they need to be kept pretty clean?[/quote]

I have never noticed any problem with the rear sensors with "normal" dirtyness but I would expect some loss of performance if you got the sensors completely covered with thick mud etc.

I have sensors on the front also and I have had the occasional false beep from them in heavy rain. The front ones can be switched off anyway for normal driving, so that you don't get beeping when driving in queueing traffic.

[quote]I guess people disable the standard reversing beeping so they can hear the sensor beep?..or is there enough difference in speed and pitch to hear both?[/quote]

Mine is not disabled, though I wouldn't mind having it done. It isn't enough of a nuisance to make a special trip, but I will probably ask when the car goes in for service. There is no real confusion between the two sets of signals. As the vehicle approaches an obstacle, the frequency of the sensor beep rises and eventually becomes a continuous tone when the obstacle is about 30cm away. I can't see any way in which I would confuse it with the standard reversing beep.

[quote name='Sagitar' post='969127' date='Feb 6 2010, 01:51 PM']There is no real confusion between the two sets of signals. As the vehicle approaches an obstacle, the frequency of the sensor beep rises and eventually becomes a continuous tone when the obstacle is about 30cm away. I can't see any way in which I would confuse it with the standard reversing beep.[/quote]

Agreed

[quote name='Sagitar' post='969053' date='Feb 6 2010, 10:24 AM']It's a filthy morning here so I left the car in the garage and just lifted the door to take the photo. I hope it will serve?[/quote]

Thanks, Sagitar - much appreciated.

For 25 quid I decided to risk buying the U301.
The seller doesn't have any listed on Ebay atm but is willing either to list one or sell privately.

The U301 comes in a UK retail box with english instructions.
The control box appears to be slightly smaller than the PD1 from pictures I've seen.

For those interested, the main chips on the board are
Atmel AT89C2051 - 8 bit programmable cpu
UTC393 - voltage comparator

Quite a neat circuit board, well laid out with clear markings of each value of resistor/capacitor etc

[img]http://www.cootuk.talktalk.net/circuit%20board.JPG[/img]


Looking inside the boot area with the hidden tray out, there's the side port for cable entry - as in the post above - and there's also a grommet about half way along that I guess is used for the ultrasonic cable entry?

There's a handy earth point along the edge of the boot at the rear of the car.

The cables to the reverse lights look a bit tight though.


I think I shall wait for a warm dry day to fit the antenna so the glue sticks properly, then will seal with silicone sealant and gaffer tape.

On reliability - we've had sensors from new on our T3 (not sure if they were factory or dealer fitted as they weren't ordered and we don't have the protection pack. Never cleaned them specifically and not had any problems with them during snow/rain etc and they get tested every day as the people opposite park their car opposite our driveway! Colour coding exactly matches the bumper as per the photo above (ours is novus grey though).

[quote name='cootuk' post='970203' date='Feb 8 2010, 05:49 PM']For 25 quid I decided to risk buying the U301.[/quote]
Would be very interested to hear your opinions of this system when fitted. I've been looking at these sensor-less systems as a much neater install option but would like to hear a users opinion of their sensitivity etc in use.