I was on the highway in a downpour. Could barley see the road. So as a test I put on the DRCC. I was in heavy traffic at 60MPH, and it worked fine. So I went for it and turned on the lane control. It didn't complain it couldn't see the lines. I didn't leave either on for long as I was hydro planning a lot.
I have been very impressed with DRCC myself. I even followed my brother home riding his motorcycle one night in bad weather without issue. Lane Keep Assist seems to work best on fresh blacktop roads where the system can easily detect the lines. If the lines are faded, I noticed sometimes it will beep but not move the wheel.
It certainly doesn't always work reliably in really bad weather. Particularly when there was a lot of really heavy rain with a lot of ground level spray. I found a couple of scary moments when I had it on the first time in these conditions, where it lost sight of the vehicle in front (the car icon would disappear on the MFD), and all of a sudden the car would start to accelerate quite rapidly towards the forward vehicle! I imagine once it got closer it would have picked it up and kicked in again, but it's not a pleasant experience and when it did this a couple of times I switched it off until the rain had gone back to a more "normal" level and then it worked fine again.
I realise this is just academic chat, but the manual does state that there systems are not for use in such inclement weather. Maybe I'm simply old and grouchy, but I don't see the point of trying to see if you can get drcc to work better than it was supposed to.
I hadn't actually read that precise bit of the manual before I'd used it (or if I had I'd forgotten it) - I suspect, like many people! The bad weather came suddenly and I didn't really think about it until it started behaving badly. I wouldn't use it in those conditions again now I know. It was only afterwards I found out the manual had specific warning about it.
It always amazes me how cruise control failure modes always seem to result in nearly the worst possible behaviors.
IMO it is not impossible to automatically detect a severe weather condition and provide warning or disconnect DRCC.
I'm going to say I would not use DRCC. It makes use of K-band radio waves and camera....both which can be effected with heavy rain, fog etc. While the K-band, radar frequencies are probably less susceptible to these things it isn't infallible. The last thing you want is for something to go wrong due to poor conditions, not to mention hydroplaning. While DRCC is pretty cool technology I would only use it in good weather.
It's quite fun on twisty A-roads (non-highway) too. It works as it should when it can see the car in front then as you approach a bend and the leading car goes round the bend, out of its field of view, it accelerates up to the set speed, which can be quite hairy. Accelerating into a bend and deccelerating out, opposite to what you would normally do. I know I shouldn't but it's fun.
I can't believe people are driving 60 mph, in a heavy downpour, and you could barely see the road! And Hydroplaning too?!? It's gotta be the nuts in Southern California…
I've never been silly enough to test it in the Prius, but cruise control will usually cancel automatically if the tyres spin up. If there is any chance of ice on the road I use the cruise control in my head. I have Nokian WRGIII tyres to deal with hydroplaning. It's not an issue, even driving through puddles, though the water WILL pull the car from side to side. So I just slow down.
Interesting feedback. BTW, I noticed this thread about adaptive cruise on Jaguars. Would the DRCC on the Gen 4 respond in the same way? "2) Once I had it set to 45 mph as I was approaching a 90 degree right turn. The car in front of me slowed down, then accelerated straight across the intersection, removing the radar object from the Jag's view. I had my turn signal on, so instead of surging ahead (too fast for my turn), the Jag allowed me to complete my turn and then accelerated gently back up to my set speed. Somebody really put some thought into programming this system." Source: Adaptive Cruise Control - Page 3 - Jaguar F-Pace Forum
Just guessing the road was at 60 MPH, as normally it's moving at 75 with 2 people doing 90 weaving between the cars. That's every road I'm on. It was just a few mile test. I don't like or use cruise control on wet roads, or heavy traffic. DRCC has to be watched very carefully, it's got some predictable quirks. The worst is when someone cuts into the open space in front of you. If that car isn't going faster than you, the brakes are coming on real hard. Enough that the car behind you might not stop. I see it about to happen and get on the gas or disconnect.
No, if it loses sight of the lead vehicle below about 45km/hr, it displays something like "NO LEAD VEHICLE- I GIVE UP". And goes away and sulks till you find the lead vehicle or speed up again - then you have to tap the C/C wand again.
Hmm, the GIII will accelerate smartly back up to the set speed when the car in front disappears. It takes a few seconds for it to notice though. But it drops out when the speed gets below 40 km/hr. It's real conservative. Good thing I guess, but it always makes me mumble about "little old ladies driving".
Wow CC, I can't believe people are doing 60 mph in such atrocious conditions, here in the UK they would be doing 80-90 mph and tailgating in such weather.
