Cruise control activation problem - Toyota Prius Forum : Prius Online Toyota Forums
User Tag List

Reply
 
LinkBack Thread Tools
post #1 of 15 (permalink) Old 10-16-2006, 02:24 PM Thread Starter
Junior Member
 
Join Date: Sep 2006
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
(Thread Starter)
Default Cruise control activation problem

I've been using my cruise control on my 06 regularly on highways and long stretches of local roads. There's never been a problem with it for the past 4 weeks since I've owned the car. It activated, maintained my speed, and I was able to adjust my speed using the control stalk.

Yesterday, I had to drive to a friend's dinner party. After driving on local roads and getting onto the highway, I decided to use the cruise control. I turn the system on using the button on the end of the stalk. The indicator on the dash reported the cruise control was activated. I then proceeded to set the speed by pulling the stalk down. I was travelling at 65mph and took my foot off the gas. Gradually my speed started dropping as if I hadn't turned on the cruise control (coasting to a stop). I tried setting the cruise control repeatedly but each time it would not maintain my speed.

I was planning on bringing the car in for service today but on my drive home last night, the cruise control started working again!

Has anyone had this problem before?
Hybridized is offline  
Sponsored Links
Advertisement
 
post #2 of 15 (permalink) Old 10-16-2006, 02:37 PM
rpm
Senior Member
 
Join Date: May 2004
Posts: 261
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Default

yes, that happens to me occasionally as well. once, I turned the cruise off and then back on, and then it worked fine. I kind of wonder if I'm not holding the lever down long enough sometimes, when trying to set it.

rpm
rpm is offline  
post #3 of 15 (permalink) Old 10-16-2006, 02:43 PM
Moderator
 
Join Date: Aug 2004
Location: Tampa Bay
Posts: 7,162
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Send a message via AIM to DanMan32 Send a message via MSN to DanMan32
Default

Do you have Coastal's EV mod? If so, it is possible it is malfunctioning and interfering with CC.
CC is controlled by one wire, by sending different resistances to ground from the stalk, and the mod taps into this control line. Although the mod is supposed to be passive, something could have gone wrong so that the expected engage voltage is not seen on the line.

Or, the stalk could have gone bad. A competent dealer can check this, first with the scan tool to see what the HV ECU sees, then taking a voltage/ohm reading to the CC input on the HV ECU.
Obviously the line itself is unbroken, otherwise you would not be able to turn the CC on in the first place.
DanMan32 is offline  
 
post #4 of 15 (permalink) Old 10-16-2006, 02:51 PM
rpm
Senior Member
 
Join Date: May 2004
Posts: 261
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Default

no mods for me. and the problem is so infrequent that, in my case, I think it's user error.

rob
rpm is offline  
post #5 of 15 (permalink) Old 10-16-2006, 03:45 PM
Moderator
 
Join Date: Aug 2004
Location: Tampa Bay
Posts: 7,162
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Send a message via AIM to DanMan32 Send a message via MSN to DanMan32
Default

Quote:
Originally Posted by rpm
no mods for me. and the problem is so infrequent that, in my case, I think it's user error.
Could be. However if you've used it a few times already, then there can't be much wrong you can do.

CC may not work in the following conditions:
1. You didn't pull (push) the stalk down far enough
2. CC hasn't been activated yet (you indicated it was showing as on (ready, available, etc)
3. You weren't going fast enough. CC works only above 24 MPH. You indicated you were going 65 though.
4. You ride your brakes, or at least the system thinks you are pressing your brakes. Usually the brake lights in the back will go on, but not always, as there is 2 switches on the pedal for failsafe. Some who had the brake recall had to have this readjusted after the recall.
5. In B mode. CC doesn't work in B.

Now don't get me wrong. I am listing the normal possibilites of why CC wouldn't work, and I am sure you covered all of them, except maybe number 4, where the brake pedal needs adjustment.
DanMan32 is offline  
post #6 of 15 (permalink) Old 10-16-2006, 03:45 PM
Senior Member
 
Join Date: Mar 2003
Location: Phoenix, AZ
Posts: 883
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Default Intermittent switch contacts

I have not opened up the CC stalk to see what kind of switch is in there, but if it has open contacts, it could be a build up of dust causing an intermittent connection. On older vehicles, this was a common problem with radios and other electrical parts.

With everything turned off, try clicking the switch on and off 10-15 times, then see if the problem has gone away. This will often clean off the contacts for awhile.

Even the old Bell telephones had intermittent switches. We used to take the handset and beat the heck out of the buttons with it, whenever they acted up. (Old technology fix - get a bigger hammer!)
Phoenix is offline  
post #7 of 15 (permalink) Old 10-16-2006, 06:06 PM Thread Starter
Junior Member
 
Join Date: Sep 2006
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
(Thread Starter)
Default

Quote:
Originally Posted by DanMan32
CC may not work in the following conditions:
1. You didn't pull (push) the stalk down far enough
2. CC hasn't been activated yet (you indicated it was showing as on (ready, available, etc)
3. You weren't going fast enough. CC works only above 24 MPH. You indicated you were going 65 though.
4. You ride your brakes, or at least the system thinks you are pressing your brakes. Usually the brake lights in the back will go on, but not always, as there is 2 switches on the pedal for failsafe. Some who had the brake recall had to have this readjusted after the recall.
5. In B mode. CC doesn't work in B.
Thanks for the brainstorming Dan. I did try many of them:
1. I pushed the stalk down multiple times, and forcefully. CC still didn't engage.
2. Yes, it indicated it was activated. I switched it on and off using the button several times too, trying to reset the system.
3. Yes, I was going ~65mph.
4. I wasn't riding the brakes, only stepping on the gas. I didn't try tapping on the brakes to reset any incorrect readings though, so this may have been the problem.
5. Wasn't in B mode.
6. The car's one month old so I highly doubt dust collection is the problem.

I suppose I'll have the system checked by the dealer under warranty. Even if they clear it, at least I'll have a record of the problem so I can bring it back after warranty expires and say it was never fully functional.

Of course if it happens again or I find out the cause, I'll let everyone know.
Hybridized is offline  
post #8 of 15 (permalink) Old 10-16-2006, 06:57 PM
Member
 
Join Date: May 2006
Location: Boone, North Carolina
Posts: 77
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Default

I'm still getting used to the Toyota cruise control. It lack the "accelerate" feature i'm used to on other vehicles. In addition, the "resume" feature seems like it will only "resume" if i'm within 5-6 mph of the previously set speed. Weird, and there is a high liklihood that it is user error on my part.

good luck with your control, .......
rangerdavid is offline  
post #9 of 15 (permalink) Old 10-16-2006, 07:42 PM
Moderator
 
Join Date: Aug 2004
Location: Tampa Bay
Posts: 7,162
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Send a message via AIM to DanMan32 Send a message via MSN to DanMan32
Default

It does both. It's just not instantaneous. Be more patient.
You can't resume CC if you dropped below 24 MPH. If you did drop below 24 MPH, CC intentionally forgets its setting and cannot resume.
I have indeed resumed to higher speeds such as 55 from as low as 40. However, the acceleration rate was not to my liking so I would usually help it along.

I usually do accelerate the CC. I can often drive the car and never touch the gas if traffic is light enough. If I see I am starting to creep near a car, I cancel CC or hid decel until I match the speed of the car I am following, or perhaps a little slower. If there's too much of a gap, or traffic has sped up, I pull the stalk up to accelerate, or if I can judge the speed difference, I'll tap up the accel stalk once for each MPH increase I desire. Now if my deceleration rate is not sufficient, then I am forced to press on the brakes. But whatever speed shifts I could accomplish with the accelerator, I can also do with the CC stalk.

Also, I believe CC's acceleration rate is the most efficient, though I haven't proven this empirically. It seems to accelerate maintaining about 20 MPG consumption during the acceleration. Although in ideal physics it doesn't matter how fast you accelerate, only the target speed matters, I believe the power plant has rates that are more efficient than others. That's why it's a hybrid.
DanMan32 is offline  
post #10 of 15 (permalink) Old 10-17-2006, 03:43 PM
Senior Member
 
Join Date: Mar 2003
Location: Phoenix, AZ
Posts: 883
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Default Cruise Control in "B" - 2002 Prius

We have a 2002 Prius, and the cruise control works in "B". Doesn't it work on the newer models?
Phoenix is offline  
Reply

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



  Similar Threads
Thread Thread Starter Forum Replies Last Post
Problem with activation hannahfras Other Vehicle Discussion 0 08-02-2010 05:35 PM
MPG vs. cruise control blubot Toyota Prius MPG & Fuel Economy Discussion 8 04-04-2007 10:25 PM
Cruise Control River Rat Toyota Prius Technical - Q & A 9 01-04-2006 06:23 PM
Cruise control Viking Toyota Prius - Technical Chat 23 08-13-2004 04:51 PM
cruise control Hep Toyota Prius General Discussion 7 08-04-2004 01:58 PM

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome