Pre crash warning on a Downpour evening.

[azuldiamondavid]

Hi 

 

Something weird happened at the weekend.   While on cruise control at a rainy night a warning light came on with a noise signal and the car canceled the cruise control.

 

I had the pre-crash on.  I do not know how to switch it off and I don't really want to switch it off anyway.

 

There was a lot of rain and I'm wondering if that was the problem.

 

The cruise control would not work on those conditions. 

 

Does someone know why this happened? 

 

How do I fix this?

[gdh300]

I think this usual for anything in a car using 'radar'. Thankfully, planes seem to be able to operate their radars in the rain!

A former work colleague has one of the latest Prius with every available modern aid. He said when we had 'The Beast From The East" as he drove through the heavy snow, one by one the aids were pinging messages saying 'unavailable'. Worth the money then.  

[SRR16]

It took me a while to realise that the Cruise Control cancels itself as soon as the double-speed wiper engages. If you have the wiper on Auto then this can happen suddenly during very heavy rain. If you manually switch from Auto to normal single-speed wiper operation, then you can continue to use the cruise control as normal. I guess that Lexus thought of this as an easy way to discourage use of the radar cruise control in bad conditions.

[DanD]

This is normal. The radar cruise control cancels out when there is too much interference like heavy rain, spray or snow, because the radar cannot accurately measure the distance between your car and the one in front.

You can, however, select the standard cruise control: switch the radar cruise control on, then immediately push the stalk away from you. You will see the icon change on the dash.

It's all in the manual.

Sent from my LG-H930 using Tapatalk

[azuldiamondavid]

Many thanks for your help guys . I’ll look at the manual too and see if I can learn how to go around this. It has been very informative. Cheers 

[Texas]

Remember that if you have used 'Active Cruise Control' for a long time and then use 'Manual Cruise Control' then keep your wits about you as you might forget to brake when coming up behind a slower vehicle... Don't ask me how I know this!!!!!!

paul m.

[azuldiamondavid]

16 minutes ago, Texas said:

Remember that if you have used 'Active Cruise Control' for a long time and then use 'Manual Cruise Control' then keep your wits about you as you might forget to brake when coming up behind a slower vehicle... Don't ask me how I know this!!!!!!

paul m.

Wow I'm scare to ask!!

 

On another similar matter  I did switch off the rear parking sensor because I had the bicycle rack on the tow bar and I forgot to switch it on when toke it all off.

 

Later on another day my wife tried to park the car and expected a noise.......... Don't ask me what happened next!!! 

 

 

[Zotto]

Something similar happened to me after switching off in a car washing tunnel: now I always remember to switch it on soon after wash. 😁

[EssexGonzo]

On 11/15/2018 at 9:21 AM, Texas said:

Remember that if you have used 'Active Cruise Control' for a long time and then use 'Manual Cruise Control' then keep your wits about you as you might forget to brake when coming up behind a slower vehicle... Don't ask me how I know this!!!!!!

paul m.

But won't the collision avoidance kick in at the last possible minute....?

[Ian J. Parsley]

Tbh, I wouldn't be too quick to look for a "work around". This is a safety feature and an entirely legitimate one. Cruise control of any kind is not designed for heavy rain.

[azuldiamondavid]

Thanks Ian for the advise. I wasn’t thinking of switching it off anyway. I gather it will be difficult for the radar to pick up anything with such heavy rain.  Cheers