Clicking Under Dash

Just ahead of your left knee is the body ecu and trac euc. There is a slew of relays in those components. I don't notice any sound, but I may be tuning it out, concetrating on driving 65 and reading fine print on the scanner or you may have one that is actually abnormally loud. There is a remote chance of a poor pin fit at the body ecu and it thinks you are cycling the door lock. Go somewhere quiet and start cycling door locks and pwr windows, anything you can think of, to see if one of your actions can get the "loud relay" to click. This will help to isolate the system with the fault.
Regards, Mike

 

I've had my Prius a week and I've noticed a clicking too. Not all the time - it might click real fast for a couple seconds - every 5 minutes or so. Not in regular intervals. Did you ever find out what the cause of yours was?

 

That wouldn't be when making turns, would it?

 

No It's weird, I can't really narrow it down to happening when I do one thing in particular. First I thought it was when I braked. But then it also happens when I'm just sitting in it going no where. Or accelerating.

Today I'm working on the theory that it happens when it's hot out. Only because I didn't notice it as much or as loud on my way into work when it was in the 60's out. But I did notice it when I took a trip to the vet around 10am when I think it was in the 80's here.

 

Have you turned off the AC? Do you still notice it?

Dan - I was going to post the same thing

 

Turned off the AC? Are you crazy? I live in Florida!!

I will try that - I have a feeling it's going to annoy me until I bring it in to the dealer for my first oil change. And I'm sure they LOVE it when a customer comes in and says "my car is making a weird clicking noise - can you figure it out?"

 

It was cool enough in the mornings earlier this week, though admittedly, was a tad cooler up here in Spring Hill.

Wait, are you hearing a clicking, or a brr noise like a fishtank air pump? The latter is the brake pump accumulator keeping hydraulic fluid pressure up. You can repeat the accumulator pump noise by pumping your brakes a few times.

 

Hmmm, I'll try that next time I take the car out. It definitely wasn't related to turning off the air, I tried that for a bit on my way home.

I noise kind of sounds like someone playing Wheel Of Fortune in my car, but only lasts a couple seconds.

 

Oh well. I've fixed the problem sort of. I just will listen to FM really loud instead of AM at a normal level and then I won't be annoyed anymore.

 

Plugs on modern cars shouldn't make too much AM noise, but it could be from a nearby car/truck. I sometimes get that too.

 

I just bought a 2008, and I hear a clicking noise too!!!! For sure when I step on the break...but other times too. I'm starting to write down when/how it "clicks" so I have somehting for the service shop to look into. Did anybody ever figure out what the "under the dash clicking was coming from"?? It can't be normal..I hope!!!

 

I've read that it has to do with the brake accumulator charging up. It does seem to happen during or just after braking. The odd thing is, I've owned 3 Gen 2 Prii now and my new 2008 is the only one that has made this noise.

On the other hand, my new 2008 seem to have way less rattles and road noise too. Hopefully it will stay that way.

 

It's brake, not break, unless your brake is broken.

The clicking is from the brake accumulator pump. Since the engine is off part of the time, the Prius uses an electrically powered pump to generate hydraulic pressure for the power brakes. The pump runs every third time or so when you press the brake pedal. The sound comes from the driver's foot well, and sounds like a clicking, buzzing, or ratcheting sound, depending on who describes it.

Tom

 

Thanks - the saleman said it was the ABS brakes, but I didn't want to just take his word!!! I guess I had a sales person who knows what he is talking about!!

An ex-Northern Michigander who doesn't like snow/cold any more!!!

 

My car has always clicked, but now it is doing it all the time! When I brake- when the ICE starts- sitting at a light. Its been a big change over the course of a week. It has also gotten hot this week. Coincidence? Is something going bad on it?

 

If you get brake accumulator pump noise all the time it means you are losing pressure in your brake system.

Tom

 

If the noise happens like every 5-10 minutes, is it a normal amount? Enough to be concerned about? I just bought a 2006 Prius yesterday and did not notice the noise while test driving it, only to hear it on the way home for the first time. I'm concerned that I've bought a car with a problem already! I do think that the noise is the same thing as what people are describing here. Any help would be great. Thank you.

 

I'm having a similar issue and I really hope it isn't the break accumulator. I'll need to post mine in a separate thread to see what you guys think. Good luck OP.