[GeorgeRace]

Having a problem with cruise, I think! Don't believe this is normal operation.

Example, step by step as to what is happening.

Driving down the interstate at 75 mph with cruise set.
I get off at an exit, leave my wife in the car with car running, and run into a store for a moment.
Get back in the car and head for the on ramp to the highway. The ramp is slightly uphill as is the highway for a couple of miles.
On the ramp at about 45 MPH I push up Resume on the cruise control.
The car shifts down, several steps, and the RPM's go to about 3250.
The car gets to 75 MPH on the cruise indicator, the ECO yellow light comes on, but the RPM stays at 3250 RPM! And it will stay there until the car starts on a slight downgrade! Then the RPM will then fall back to about 2200 RPM.
The longest distance this situation has happened is just over 4 miles, very slight upgrade then level driving, and finally a slight downgrade, where it goes back to normal.

There are times when the RPM's go as high as 4000 RPM, and stays there, again with the yellow ECO light on at 75, until I start a slight downgrade.

I currently have my Toyota Dealer looking for a solution, so far they have not been able to recreate the situation on any other similar car. During the high RPM situation, the MPG bar graph is showing about 18-20 MPG!

Has anyone else seen this situation? If so, what was done to correct it?

 

[CamRod1]

I've noticed once or twice that it seemed to take longer for the car to shift back to sixth and RPM to drop back to approx. 2200 and only as I started to decend. Normally set my cruise to 75 as well. It's only done it a couple of times so no concern to me and I drive the same route weekly.

Not sure what my ECO lite was doing as I don't pay much attention to that, but an ECO lite at 4k doesn't appear right.

Probably a software glitch. Next time it happens and you think the motor should unload back down to 2k tab the left paddle down a gear then hold the right down a few seconds to get back to D (6) and see if it responds. You can also try blipping the throttle.

Keep in mind any headwinds that may keep the car working harder than normal, but if that's the case you shouldn't have an ECO lite.

 

[OldMajorDave]

Hey George…good to see ya back… but tough deal with this new “adventure”. I’m guessing Camrod is correct about the software error for your particular scenario, but to be honest (and not to be a smart butt), I’ve never even thought of exiting an interstate, pulling into a shopping area, sitting around with the engine running and the car in park, and then scootin’ back on the interstate and expecting the cruise to resume. Perhaps it should work… but it seems to me that with that scenario there would be enough brake and transmission input alone to confuse the hell out of a main-frame. Likely just old school habits… but exiting a cruise I’ve always just turned the cruise off. It’s not even something I think about. …But I also piss-n-moan to every family member if I get into one of our cars and find the cruise is left on…lol.

At-any-rate… if your car experienced the RPM issue when not controlled by cruise, I’d be worried (computer, torque converter…etc.). Since it only happens under that specific circumstance…like the old doctor says to the patient who complains of a little pain while contorting his leg in yoga knot… "just don’t do that anymore".

Best, Dave :laugh:

 

[GeorgeRace]

Hi Dave, well there is always more to any story. What I did was give an example that is repeatable. But, the problem happens in many ways. If you tap the break in traffic, then pull out and hit Resume at at least 10 MPH under the cruise set speed, it does it. Anytime you come up behind a slow truck, the the auto cruise holds you back. You pull out Resume happens automatically, then cruise immediately goes to 3 to 4K RPM, and the problem repeats itself.

So it is just not with reentering the highway that causes the situation. I guess that I could say that anytime you have cruise set, and then apply resume at 10 MPH or more less they the set speed, this situation ALWAYS happens, but the only time it stays at a high RPM, with the ECO light on, is when you are on any type of uphill grade, or on perfectly level road. The slightest downgrade and the RPM's immediately drop back to normal.

And on leaving the highway and them getting back on, after a short store stop, my Wife would not want to set in the car waiting, in 90 plus degree temperatures, while I ran into a store for a quick purchase. So the cruise stays as it was on the road.

All the best,
George

 

[OldMajorDave]

Sorry George, guess I was thinking basic Cruise Control… while you have the Dynamic Radar Cruise Control and the Lane Departure Alert stuff (George’s Adventures correct). If the vehicle operates normally without cruise engaged and RPM/shift issues are encountered only with cruise engaged …then that’s going to be a tough one… that has to be computer/tcm firmware related. If you test drove a ’17, I wonder if you’d find any differences in behavior in similar circumstances or in the displayed firmware versions. If the dealer says they don’t have a clue then an evaluation by a regional rep is generally the next step. Stay on them! Hope you get this sorted…

Best, Dave

 

[sycohen]

Tachometer behavior

I have a 2016 XLE with the advanced technology package.
I've noticed some strange behavior of the tach when the auto follow function is engaged. i find the rpm's jumping to 3000 or down to 1200 on slopes, but with no change of engine sound. Under normal driving conditions, cruising at,say, 70mph, if I accelerate to 3000 RPM from 2000, there is a noticeable change of engine note and a gear change. in the case of being in cruise control the tach will jump to 3000 with no change at all. Then it will go to 1200 or so, and finally settle back to 2000. This has led me to believe that some of these tach changes are computer related and not engine related. I don't know how to even start explaining this to a Toyota service advisor.

 

[GeorgeRace]

Gosh, sounds just like what mine has been doing since I got it new in April.

My Dealer had absolutely no idea what I was talking about, so took my cell phone, put it on movie and went to some ramps with long grades on to an uphill piece of highway, running the movie camera showing the Speed, RPM, ECO light and the center cruise control display with set point and speed.

I finally got to take my Service Manager for a ride and demo the problem to him. I then provided them with the videos, 2 of them showing the problem. He forwarded it to their Factory Representative and guess what, next Friday I get to take the Factory Rep and my Service Manager for a ride. I guess this may lead to a solution.

This is the same Factory Rep that had my brand new 2012 XLE roof clicking, and left pulling on the road problems, repaired and paid for by Toyota. He actually had my car for 3 days and used it to train my Dealer how to tear apart the roof area, and repair the Moon Roof Clicking Problem.

So, I have faith that this will finally get enough attention to be repaired, and a service related repair notice issued. Will post the outcome of next Fridays findings here.

George

 

[jblackburn]

Car thinks it's on a hill, and doesn't shift up until it can maintain speed without throttle applied so that it's not hunting for gears in the ascent. That scenario is specifically programmed into the transmission logic when on cruise control.

 

[GeorgeRace]

It's Friday and I am back!
As I stated earlier, today was the day to meet with the Toyota GeorgeTown KY Plant troubleshooter.
We went for a drive and the car did exactly what I said it was doing several times. Took a new 2016 Camry for a drive, and what a difference there was.

So he is writing up the behavior for the Engineers to ponder over, and sending them a couple of my videos of the problem that I took with my cell phone.

Expect some sort of an answer, about what is going on, in a week or so.

He feels that it is a software problem or conflict between normal cruise and Radar Cruse, and could be as simple as changing the appropriate piece of software in one of the computer modules. So I guess time will tell.

Will get back here, hopefully with an answer, when the next step occurs.