Cruise Control stopped working...

The repair manual suggests the following possible causes:

Cruise control switch circuit
CRUISE main indicator light circuit
Combination meter​

Hybrid vehicle control ECU

 

Also, do you have a check engine light on? I don't know about the Prius, but I had another car (Saturn Vue) where the cruise control was inhibited when the check engine light was on.

 

Some 2004 Prius get their brake light switches replaced for free because of a defect that could cause this symptom. A good Toyota shop will know if yours is on the list.

 

I've only had that happen once....turned out I had bumped the "shifter" into B and didn't realize it. As soon as I put it back in drive, the cruise worked fine.

 

My cruise stopped working one time. I pulled over and stopped. Shut the car down and re-booted (don't know if this is the right term?) and the cruise started working again. This was about three months ago and I haven't seen this problem since.

Mike

 

My Prius has less than 1000 miles on it.

I was driving in a hilly area in California and later in the day after my cruise control had been working fine, I noticed that it wouldn't stay at the speed I had set for it... If it was set for 60 mph and when I came to a down hill it would just keep climbing in speed, once up to 80 mph... Then when I would reset it on the level or going uphill it seemed OK. It has now happened several times and I just assumed that it was a poor design or a temporary bug... But it could get me a speeding ticket...

Any suggestions?

 

Suppose that while you were heading downhill, cruise control was not engaged and you let go of the accelerator pedal. What would happen to your speed: would it decrease, remain constant, or increase?

If your speed would decrease or remain constant, then cruise control should be able to maintain a constant speed.

If the slope of the downhill run is sufficiently steep so that your speed would increase when cruise control is not engaged, then when it is engaged, your speed would also increase. Cruise control will not invoke engine braking to help reduce your speed.

 

Shift into "B" on downgrades.

Bob Wilson

 

If the hill was that steep, cruise control can't maintain a speed, nor was it intended to. try using your brakes, because the cruise control sure can't.
It's no an autopilot.

 

Thanks guys for the edumakation.

The hills were not that steep and as soon as it got to a level area then it would go back to cruise at the adjusted speed.

My Mercedes car and my BMW bike's cruise control would automatically continue the set speed, up and down these same hills. That is what I expected with my Prius.

I have never had to apply brake on these same hills (Hwy 5 & Hwy 152 - just east of Monterey) and the cruise control would back off or add to the speed as needed to maintain, say the 60 mph. I just thought that the prius would do the same but it didn't, though when heading west on the same road it did work as I thought it should, but coming back is when it acted different and seemed to fly down the hills and act erratic, then correct itself when it became level.

Maybe I am missing something but that's my story and I'm sticking to it!!! lol

 

I do have a question: While using the cruise control can you shift into B and still maintain the cc setting???