Newbie ? ... should I press button to turn AHC off

[cwmoser]

I've only owned my 2002 LX470 for two months.
The AHC works as I can lower it and raise it but it goes back to normal after about 20mph.

There is an OFF button for AHC ... when should one drive the LX with the AHC off?

 

[Josh N]

The AHC off button keeps your truck at normal height and keeps it from reacting to road conditions (dropping back down at 20 mph is correct), essentially giving you a psuedo stock suspension set up compared to a truck without. With the AHC on your truck compensates for bumps in the road, body roll etc. and can deliver an extremely smooth on road ride. The only practical application I can see for turning off the AHC is offroad where you are running at a low speed but keep bumping up above 20mph to keep the truck from trying to react.

 

[uHu]

The AHC-Off is mainly for use when standing still, and it will turn on again when you get up to speed.

In Lo, it will go up to N at 3 mph, regardless of the ahc-off is activated or not.
If in Hi, it will return to N at 19 mph, if in the high gear range.
With the transfer in Low, the ahc will stay in Hi up to 31 mph, then go to N, and return to Hi if the speed again goes under 12 mph.
If in N height, and the ahc switched off, the ahc will turn on at a speed of 50 mph, iirc.

 

[nnnnnate]

Thanks for those additional speed specs uHu. I knew the basic parameters but wasn't aware of the additional speed allowed while in low.