Cruise Control Speed

[janmeeks]

Drove a 2002 LS430 for 15 years and recently bought a 2020 LS 500.  I use the cruise control a lot and am frustrated that it will not "hold" the speed at the same speed I set.  For example, if manual cruise (not radar) is set at 80, the actual speed is only 79.  Very seldom will it hold the cruise speed.  I've taken it in for service and am being told that is "normal".  Does anyone else find this to be true..........it was never so with the old version and my husband drives new model GMC's which do not do this either.  Will appreciate feedback so I can either get over being annoyed OR get the problem resolved!

Thanks!

[1990LS400]

I would expect the actual speed to be slightly less than the speed shown on the speedometer.  The difference is usually between one and three mph.

After setting the cruise control speed you can adjust the cruise control speed with the steering wheel controls to get it to exactly where you want it.  

Do you not like the Dynamic Radar Cruise Control?  All vehicles manufactured by Toyota since around 2018 have it.  It takes some getting used to and even some skill to use efficiently.  I've often driven 200 miles or more while using radar cruise control without ever touching the gas or brake pedals.  

[janmeeks]

Thanks, Jim.  Every car my husband and I have owned has kept the cruise speed constant - this is new to me and quite frankly, annoying.  I actually took it to the dealer, they said nothing was wrong, and it's been holding speed ever since!  Weird.

Re the radar:  I think I'm too much of a control freak to ever let the car drive me!!!!  I'm an aggressive highway driver so find myself close behind people in the left lane fairly often.  

[1990LS400]

10 hours ago, janmeeks said:

Thanks, Jim.  Every car my husband and I have owned has kept the cruise speed constant - this is new to me and quite frankly, annoying.  I actually took it to the dealer, they said nothing was wrong, and it's been holding speed ever since!  Weird.

Re the radar:  I think I'm too much of a control freak to ever let the car drive me!!!!  I'm an aggressive highway driver so find myself close behind people in the left lane fairly often.  

If the adaptive distance sensing feature of your cruise control no longer works, the dealer must have deactivated it with Techstream or via an in-dash setting that you can control yourself.  

Laser based adaptive cruise control was available in all years of the LS430 in the Custom Luxury and Ultra Luxury packages.?  Its laser sensor was in the lower grill on the passenger side.  The LS430 got radar based adaptive cruise control and automatic emergency braking for the 2004 model year as an option on top of the Custom Luxury and Ultra Luxury packages.  It's radar sensor was behind the "L" emblem in the front grill like it is on your LS500.

Radar based adaptive cruise control is one of my favorite features.  All our current vehicles have it.  I won't even rent a vehicle without it.

Even a fully autonomous driving vehicle requires oversight from the driver.  One can't just "zone out" while the vehicle is driving itself.   Some who have done that have made the news by crashing.  I'm rather looking forward to full self driving vehicles.  A 700 mile medical related trip last week sure would have been less tiring with that.  I would have bought a Tesla with the full autonomous driving option by now if there were enough convenient charging opportunities where we drive or if they had substantially longer range on a charge..