K20FTY

Here is part of the circuit diagram for the clearance sonar system, along with parts location diagrams. Lexus seem to regard Clearance Sonar and Parking Assist as two distinct parts of an overall Parking Assist/Monitor system
There is an extra part of the circuit diagram when the sonar system is linked to the parking assist functions, but I don't think that applies to Paul's and my cars.
There are lots of pages of the workshop manual dealing with trouble shooting and testing and settings, but they all require the Intelligent Tester - that's a bit of kit which dealers have which is used for all sorts of things. It is not the same as TechStream which I don't think will help here.
Intelligent Testers come up for sale occasionally, but they cost about £300.

Not so fast - mine has the parking sensors at the rear - not at the front - but it doesn't have a light on the dash to say parking assist is working, it doesn't show up on the multi-information display, it doesn't show up on the satellite switch settings (only speed and tach are there) and it doesn't beep when selecting reverse.
But it does beep (progressively faster) when you reverse up to an object.
I can't just think of what Ian can check, but don't give up yet!

Thanks Paul - you’ve come to the same conclusion I did - I can’t think of any other reason than a new bumper at some point... :(

So in that menu list it does say ( If Equipped) after Parking Assist and some others but not after the Speed & Tachometer Indicator feature,
So I guess All cars have the Speed & Tachometer feature and the other features are options, therefore could it be possible that your car has been fitted with a replacement rear bumper at some point that has sensors in it from a car that had  this feature and your car does not?
Paul m.

On your 'Satellite' switch ( as Lexus call it) is the parking assist ON?
Paul m.

Seems a bit of an odd one to me, but here goes...

I have a 2006 IS250 SE, without NAV, it has physical sensors in the rear bumper, (none in the front), but the car doesn’t beep when selecting reverse, or when reversing towards an object (even a solid wall), and I’ve never seen the green parking assist light on the dash.

There’s the correct fuse in the passenger footwell fuse box, and it’s not blown.

I’ve read about a ‘switch’ in the boot to turn it off if you’re towing a trailer, but can’t find any sign of one (unless it’s hidden under a trim panel), and there’s no sign of it ever having a tow bar fitted.

Anyone got any thoughts on what’s going on, or know if it’s something that a dealer could have turned off? (If so, could I buy tech stream & turn it back on?)

Thanks in advance!

Hi folks,

New to Lexus ownership, (2006 IS250 SE) and the forum. Looking for recommendations on a good OBD2 scanner - TIA!

A few pics, as requested - please let me know if they should be in another section...

Excellent choice of Motor ( but then perhaps I'm a bit biased)
Lots of info here https://www.honestjohn.co.uk/carbycar/lexus/is-2005/ to give you an insight into your new ride, that is unless you already know all this from doing research before your purchase!
Cheers Paul m.

New (to me - 2006) IS250 owner here - looking forward to lurking & finding lots of good info...

I did a quick search for LEXUS on the Tapatalk app, and there you were!