Doublepump

Ok, there is a post on this on another forum that I am not a member of, but was wondering if anybody had any issues/problems with their HAC/DAC. The guy had posted that his HAC plain doesn't work for him, so I was wondering what people's experiences have been with it.

The manual states that it helps to prevent roll back, but doesn't actually say that it stops the vehicle and also states that it may not work on very slippery surfaces or very steep grades.

So, I went and tested mine on a very steep, paved hill, (dont know degree), that is by my house. I stopped on the incline and let go of the brake (4W Hi, D). The light with the vehicle and the wavey tread marks came on and I immediatly began to roll backwards, and I could hear the system doing something. It slowed me down for the 5 sec, and would release and I would roll back faster, then it would come on again and slow the vehicle. However, it never held me in one position. So, not sure if it should due to the angle, (guess I should try and figure out the angle). I was able to put it in 4W Lo, D and the truck stayed right where it was on its own, no computer assist systems came on. Now, on the way down, I put it in 4W Lo and hit the DAC, and that worked fine. Lots of noise and jerkiness but it kept the vehicle to a crawl. When I took it out of Lo and turned off the DAC I started to gain alot of speed going down the hill. So, I know the DAC works.

I have tried to get the HAC to work on not so steep hills, but I dont think they were steep enough, (driveway, smaller hills in area), because the vehicle wouldn't roll back, and the light with the tire tread marks never came on either.

So, just wondering how it works for everyone else. Sorry for the long post.

JGage

I got mine to kick in (reverse) on a really bad hill/parking lot @ a place I like to eat. However, I have engaged the DAC button on the same hill and it's didn't engage.

No, it doesn't STOP you, but it slows you down... At least the reverse version.

jharris2

Doublepump -

I am familiar with the thread you reference. In testing my 4Runner today, it behaved just like yours does, except I had mine in 2WD. I simply wasn't thinking fast enough to also test in 4WD.

On a lesser grade, it held the truck in place.

BT17R

Good writeup, DP. Mine works the same as yours, tested under similar conditions. HAC only holds securely for a few moments and then lets you slide back, as described in the manual. It's designed to hold only as long as it takes to move your foot from the brake to the throttle. The steeper the hill, the more likely you are to begin rolling backwards. Pretty useless feature, IMHO. Like you noted, DAC only works in 4L.