RX400h front parking sensors

[rynd2it]

My 07 RX400h is fitted with the Lexus option front & rear parking sensors, which after some investigating, are now working. However, I say working as the spec states that the front sensors will sound the alarm if the cars is moving forward within a certain speed range and detects an obstruction. All well & good but mine will sound when I switch on the ignition if I'm parked close to an obstruction. I can use the button to turn this off and indeed this button is supposed to turn them off (or on) but it seems to revert to ON everytime the ignition is switched off and back on.

Is this normal behaviour and if not does anyone know how to switch the front sensors off permanently?

Thanks

 

David

[sorcerer]

My RX300 doesn't have them so I may be talking rubbish but yes, logically I would think that's normal behaviour. They are a safety feature so by default they should be on. There may well be times when you want or need to turn them off temporarily but when you turn the ignition back on again the car is smart enough to enable the safety feature again in case you forget to do it.

It may be a setting that can be altered from within the Toyota Techstream software but I wouldn't expect the driver/end user to be able to permanently disable it.

[rynd2it]

1 hour ago, sorcerer said:

My RX300 doesn't have them so I may be talking rubbish but yes, logically I would think that's normal behaviour. They are a safety feature so by default they should be on. There may well be times when you want or need to turn them off temporarily but when you turn the ignition back on again the car is smart enough to enable the safety feature again in case you forget to do it.

It may be a setting that can be altered from within the Toyota Techstream software but I wouldn't expect the driver/end user to be able to permanently disable it.

If what you say is true why is there a permanent on/off switch for the rear sensors? The manual gives no hint that the fronts cannot be permanently off - I for one never use them.

[sorcerer]

Ah, well, there you've got me - I did say my car hasn't got them so I didn't know there was a permanent on/off switch for the rears

I'm sure someone who actually has them will be along shortly to put us both in the know.

[tom123]

On 9/3/2016 at 1:13 PM, rynd2it said:

My 07 RX400h is fitted with the Lexus option front & rear parking sensors, which after some investigating, are now working. However, I say working as the spec states that the front sensors will sound the alarm if the cars is moving forward within a certain speed range and detects an obstruction. All well & good but mine will sound when I switch on the ignition if I'm parked close to an obstruction. I can use the button to turn this off and indeed this button is supposed to turn them off (or on) but it seems to revert to ON everytime the ignition is switched off and back on.

Is this normal behaviour and if not does anyone know how to switch the front sensors off permanently?

Thanks

 

David

The parking sensors in my RX 400h do exactly the same. Never really bothered me that much to be honest.

[rynd2it]

Bugs the heck out of me. I don't see the logic of being able to permanently disable the rear sensors but not the front.

[sorcerer]

Just a complete guess but it may be that if your car has a reversing camera then you can turn off the rear sensors and still have one safety device in action, whereas the front ones, being the only safety device at that end, can't be switched off?

[rynd2it]

1 minute ago, sorcerer said:

Just a complete guess but it may be that if your car has a reversing camera then you can turn off the rear sensors and still have one safety device in action, whereas the front ones, being the only safety device at that end, can't be switched off?

But they can be turned off, just not permanently. It makes no sense that they sound a warning when the car is stationary, parking brake on and engine not running.

Someone must know how to turn them off

[steve2006]

According to the technical sheet for dealer programmable options the fronts cannot be turned off, the volume of the warning sound can be set only.

http://www.clublexus.com/forums/attachments/rx-2nd-gen-2004-2009/113998d1194535434-how-to-set-lexus-personalized-settings-lexus-personalisation-settings-rev.pdf

[rynd2it]

25 minutes ago, steve2006 said:

According to the technical sheet for dealer programmable options the fronts cannot be turned off, the volume of the warning sound can be set only.

http://www.clublexus.com/forums/attachments/rx-2nd-gen-2004-2009/113998d1194535434-how-to-set-lexus-personalized-settings-lexus-personalisation-settings-rev.pdf

There is one item there that might give a clue  NON -P/R RNG SEN  Function to set available sensors when shift position is not in P or R / F, Rcrn2 or F. I might give it a try. Failing which cutting the cable should do it ;-)

[ChrisKaye]

Wire in a hard toggle switch maybe?

As for being able to disable the rear noises but not the front would primarily be down to people who tow a lot I imagine!

Also, if the beep chimed for the front sensors as a 'system ok' noise then that could be the reason why it cannot be disabled. If no beep or weird noise told you the system was faulty, that's preferable to rear ending a car when parking and finding out the hard way?!

Sent from my Iphone using Tapatalk

[rynd2it]

30 minutes ago, ChrisKaye said:

Wire in a hard toggle switch maybe?

As for being able to disable the rear noises but not the front would primarily be down to people who tow a lot I imagine!

Also, if the beep chimed for the front sensors as a 'system ok' noise then that could be the reason why it cannot be disabled. If no beep or weird noise told you the system was faulty, that's preferable to rear ending a car when parking and finding out the hard way?!

Sent from my iPhone using Tapatalk

You are correct on the towing aspect. A system OK single beep would be acceptable but right now my sensors go off continually when I switch on and I'm parked close to another car or a wall. That's plain dumb and I'm sure it isn't as they intended but I can't get any sense from Lexus.

[sorcerer]

On 07/09/2016 at 4:11 PM, rynd2it said:

You are correct on the towing aspect. A system OK single beep would be acceptable but right now my sensors go off continually when I switch on and I'm parked close to another car or a wall. That's plain dumb and I'm sure it isn't as they intended but I can't get any sense from Lexus.

Do you mean that you can't just sit there listening to the radio, while (for instance) waiting for your partner to come out of the shop or something, if there happens to be something in front of you?

[rynd2it]

19 minutes ago, sorcerer said:

Do you mean that you can't just sit there listening to the radio, while (for instance) waiting for your partner to come out of the shop or something, if there happens to be something in front of you?

Not unless I turn the sensors off - makes no sense at all

[sorcerer]

Wow, now that really does defy all logic. Now I can truly appreciate your frustration because there are many, many times when I listen to music while I'm parked up and waiting for something/someone. What an utterly crazy situation!

[rynd2it]

I have an update - after a long and arduous research project I have come to the conclusion that "Lexus Strikes Again". Reading the LPA800 manual very carefully it states that the front sensors are deactivated above 10km per hour and reactivated below 10km per hour. This implies that as 0km per hour is less than 10 the sensors are active when stationary. Dumb!!

So now I start the research to find the gear selector indicator for 'D' and make sure the sensors are not active unless it is in 'D' - wish me luck, long term project though ;-)

David

[rayaans]

My RX450h and IS300h both have parking sensors front and rear

They sound in all gears if close to an object apart from Park which I would think is how they should work. 

The sensors should be working when stationary. 

 

[rynd2it]

49 minutes ago, rayaans said:

My RX450h and IS300h both have parking sensors front and rear

They sound in all gears if close to an object apart from Park which I would think is how they should work. 

The sensors should be working when stationary. 

 

My rear ones only work in reverse - as you would expect. The front ones work in all gears and when stationary which is nonsensical, especially when getting into the vehicle after parking close to an object.

 

[rayaans]

28 minutes ago, rynd2it said:

My rear ones only work in reverse - as you would expect. The front ones work in all gears and when stationary which is nonsensical, especially when getting into the vehicle after parking close to an object.

 

All cars have parking sensors which work when stationary. 

Otherwise if you stopped, it'd stop beeping and then start beeping when you creeped forward.  It'd keep cutting in and out when creeping towards a car when parking in a space

[rynd2it]

59 minutes ago, rayaans said:

All cars have parking sensors which work when stationary. 

Otherwise if you stopped, it'd stop beeping and then start beeping when you creeped forward.  It'd keep cutting in and out when creeping towards a car when parking in a space

Exactly what I would expect and experienced with every other car I've owned which had them.

[rayaans]

4 hours ago, rynd2it said:

Exactly what I would expect and experienced with every other car I've owned which had them.

That's really odd.  I've driven plenty of different cars with from parking sensors and they all beep in "D" regardless of speed. 

[rynd2it]

8 hours ago, rayaans said:

That's really odd.  I've driven plenty of different cars with from parking sensors and they all beep in "D" regardless of speed. 

That would be OK - but mine beep in 'P'  'R' 'N' and 'D' which is unusual.

[rayaans]

2 hours ago, rynd2it said:

That would be OK - but mine beep in 'P'  'R' 'N' and 'D' which is unusual.

My front ones only beep in D so I would assume the wiring might have been done wrong.

As far as Im aware, the RX400h ones are dealer add ons rather than optional extras and they wire them up. 

[rynd2it]

1 hour ago, rayaans said:

My front ones only beep in D so I would assume the wiring might have been done wrong.

As far as Im aware, the RX400h ones are dealer add ons rather than optional extras and they wire them up. 

Yes, option  LPA800  and we  have  checked  the  wiring  as  far  as  possible. I  plan  on  adding  a  relay  from  the 'D' sensor  to  override  the  power  feed

[cachaciero]

Just a thought, I have been looking at fitting third party after market sensors to my RX400H, this in turn has LED me to research CAN bus add ons which will enable the sensors below 5 mph AND disable them if the Parking Brake is set so do the genuine Lexus ones work the same way? do you need the parking brake set to kill the front sensors?