Originally Posted by williakz

As background, here is some material I posted on DRCC shortly after I got my 2013 LS460 in February of 2013 and was able to put the system through its paces. Since then, BSM capability, now ubiquitous across many different makes and models, seems to give a lot of drivers new-found confidence to force the "gap" more than they ever dared to before when everything was purely visual. Cars are always jumping in front of me into gaps of less than two car lengths at speeds up to 60mph. Using the typical "2-second" DRCC rule, the minimum gap at 60mph would be 176ft or TEN CAR LENGTHS! Good luck keeping that gap free and clear at anything close to the set speed, DRCC!


General Comments:

Dynamic Radar Cruise Control definitely has a learning curve associated with it. It works best in the simplest situations and becomes progressively less useful as traffic density - and complexity - increases.

First, the system is quite a bit sloppier in speed regulation mode than I'm used to. My previous LS with "standard" cruise regulated speed to +/- just a few mph. DRCC is happy to let me go 5 to 7 mph over the set speed. That's a bit much if your set speed is already over the posted speed limit (PSL). That said, the system is quite responsive in distance regulation mode, braking almost exactly at the same time I would (so you don't feel panic that the system is sleeping) and applying the brakes firmly but not abruptly. Note that this version of DRCC will brake the car from whatever the set speed is all the way down to a full stop (say for the one red light in a small town along a two-lane highway). When this occurs, you must goose the accelerator just a tad to get DRCC back in action once the light turns green.

The system really fails in moderate to heavy freeway traffic because the separation distance between me and the car ahead is just too large. It encourages cars behind me to pass me on the right and jump into the two-to-three car length space in front of me. When they do, DRCC slows down to maintain its minimum separation and the next guy pulls the same routine and so on and so on. The way to get around this is to override DRCC's gap by closing it manually until conditions become slightly less congested. I should note that if Lexus shortened DRCC's "gap," the system would have to operate much quicker and braking and acceleration would necessarily become somewhat more noticeable, possibly to the point of annoyance.

You must always "tend" the system. If not, you can find yourself in some dicey situations. For example, you're on a 65mph PSL four-lane highway that slows to 55mph then 45mph then 40mph as it passes through a small town with several traffic lights (all green). Your set speed is 73mph and you're in distance regulation mode with the guy in front of you going at exactly the PSL at all times. Eventually you find yourself going 40mph behind him when he decides to move out of your lane so he can pull into the Burger Doodle. If you haven't been paying attention, you'll find yourself doing the PSL (40mph) with a 73mph set speed and an open road ahead. The car will take off like a banshee and you'll be the one screaming! Therefore, I always make sure I'm lowering (and raising) my set speeds as the PSLs go down (and up) even when I'm in distance regulation mode. So, no surprises. Note that this same effect can occur when you change lanes causing the mode to go from distance to speed regulation. You think you're just making an easy lane change out from behind a slowpoke, but the car sees open road and rapidly accelerates to reach its set speed. It is disconcerting to say the least. DRCC demands your attention! Probably it becomes second nature after a while, but I don't have the knack quite yet.

Specific Criticism:

The folks in the right lane are motoring along, as is their wont, at somewhat below the PSL. The folks, including me, in the left lane are zooming along at or above the PSL. The actual separation distance at 70-75mph in the left lane is NEVER more than THREE CAR LENGTHS. We have a stable system wherein the pokies are happy and the speedies, while never quite happy, are satisfied they are running as hot as possible. We have a Q-point!

UNTIL, that is, I push the fatal button and DRCC cracks open its gimlet eye, emits a low growl, and drools in anticipation of the havoc shortly to be visited on the hapless motorists of the interstate. I set speed to current with a downflick, up it by 5mph with a precise 0.75 second upflick, double-tap the distance separation button to short and WE'RE OFF!

But wait a minute. Why is the car slowing down? And how can I tell the guy behind me who's suddenly flashing his highs and beeping his horn that he just needs to hold his horses. DRCC will stop slowing in heavy traffic when it achieves a SEVEN or EIGHT CAR LENGTH gap in front of me. Oh, and how to let the pokes on my right now going faster than I am know that they are NOT to jump left into the huge gap DRCC is creating in front of their disbelieving eyes; no, they are to keep staring at the back of the truck they have been following for 25 miles! And then, when the pokes DO jump into the gap, causing me to slow again, is there anything at all I can say to the angry speedy behind me to keep him from cutting right into the space vacated by the pokes and then gunning it and cutting into my gap (raised middle finger and all), thereby causing me to slow again. The sinking feeling in the pit of my stomach is the realization that a new set of pokes and speedies are already moving into position for another round of the "DRCC Grand Slalom." Oh boy!

And this is what constitutes a state-of-the-art dynamic cruise control system? Sheesh...

Originally Posted by hawaz123

Hello i am that i could see some one talk about the lazer cruise control
I need help please have a 2001 ls430 and i have a problem with my dynamic cruise control
Every time i try to ingage the cruise i get a massage stating check cruise system. I took it to dealer they found code p1572 tech told me that the lazer needs aligne. What can you help me with cause i am reading other fourms
Ppl had this code they had to replace lazer and ecm. Help please thank you