Clicking and beeping with rollback?

[Cumby]

I'm just not sure if this is normal or what it is? On my 05 v8 4x4 if I let it roll backward on a hill a little too fast and then hit the gas, I get clicking noise and the vehicle seems to stall out and a beeping alarm come on. It only does it when starting on a significant hill and rolling backward before trying to accelerate.. Just wondering if anyone could tell me what that is and if it's supposed to be acting like that?

 

[JB.]

It's called hill start assist. HAC for short I think.

Normal

 

[SSt4r]

Yes, normal. It's "supposed" to keep you from rolling backward (for a moment only) when starting on a hill.

 

[Cumby]

How does it work or how do I work it, rather. I feel like I need to go from the brake to the gas quickly or it will start rolling, clicking and beeping if I'm not fast enough...almost like a manual transmission. Are you supposed to just let of the brake and it will engage without hitting the accelerator?

 

[Dominic]

If the computer detects that its rolling back, it'll put the brakes on for a couple seconds so you can get on the gas, here is a good link.

It's not bad for the vehicle, just let go of the brake and get on the gas like normal.

Toyota Global Site | Technology File

 

[Fern]

Good to know. I thought as the rear wheels turned upon acceleration up the hill and the front end lifted up the atrac was working the front since the wheels don't rotate as soon as the rears. If that makes any sense.