Failed AHC Switch? (1 Viewer)

[BlairB]

Currently on the hunt for a 100 series and found one I like, but it seems to be having AHC troubles. I was curious if anyone has ran across this before?

Here is what the owner is describing

• Originally the height control wasn't doing anything, but after leaving the car a few weeks it now goes into H without issue. Once in H it will go back down based on speed, but not from the switch.
• The vehicle will not go into L. No flashing L indicator, just no reaction to the button.
• When you hit the OFF button on the AHC nothing happens.
• The comfort/sport ride control seems to function normally.
• The vehicle seems to be auto leveling normally.

I am (hopefully soon to be) new to 100 series, but it sure sounds like just a switch to me? I have searched but haven't seen any other common things it may be, but figured I would check with the great minds here!

 

[BlairB]

Bump!

 

[suprarx7nut]

Yup, that's come up on here before. I'm not sure how common it is, but there have certainly been dead switches documented before.

If you connect to the ECU via techstream or OBD Fusion you can watch the ECU response and determine rather easily if the switch is bad.

 

[Smotride]

For me I’ll say do yourself a favor by buying a vehicle that has been properly maintained by its owner. Flushing the AHC system takes an hour and about $60 in Toyota-brand fluid.

 

[Smotride]

For me I’ll say do yourself a favor by buying a vehicle that has been properly maintained by its owner. Flushing the AHC system takes an hour and about $60 in Toyota-brand fluid.

Do this at recommended service intervals, and the system will outlast a lot of the other subsystems on the vehicle. Never had a lick of trouble with mine.

Some folks are the Wait-Til-It-Breaks-Then-Fix-It mentality, and others are the Ounce-Of-Prevention mentality.

 

[BlairB]

Thanks guys. Agreed on a properly maintained vehicle. This one seems pretty darn clean overall, with this being the only issue. Up in the air on it, but figured I would check to see if there is any other common things that could cause this.