jberry

Hey guys. I am having a 2004 LX 470 with 116k miles inspected by Toyota today. Any common issues to have them look for?

Ishinc

Definitely check and recheck the AHC suspension. Play with the height buttons and make sure they work, although they won't tell the whole story if the AHC system is down. The ride is usually terrible, either super bouncy or super stiff. The system is great when it works but be prepared to fork out lots of cash when it breaks (if you want to keep it). There is also a way to check if accumulators are working by going from L to H and counting the marks on the AHC fluid tank in the engine bay. Lots of searchable information on this. Good luck!

hankinid

Make sure timing belt and associated pieces were replaced around 90K. Replace the heater hose "Ts" as a matter of course.

PADDO

Let me clear something up here. The damper system L to H reservoir graduation counting check is a good general indication of the collective health of the four damper accumulators, emphasis on collective health, and is a recommended procedure in the FSM. Four new damper accumulators will return 14+ graduations of fluid level variance and Toyota/Lexus recommends replacing all four when they can only return 7 graduations (or 8 for Australian vehicle’s). Furthermore, the vehicle’s neutral pressures need to be within their respective ranges for the L to H test to be as accurate as possible. The best available method for checking the damping at each corner of the vehicle is to enter AHC diagnostics test mode and conduct the 16 Step Test; basically the damping is initially set to 1 (softest) for the front and rear circuits and you walk around and push each corner down and get a feeling for the dampening response/resistance. You then step the system to 2, 3...... each time checking the dampening response. You will feel any non responsive corners which may well indicate a ruptured accumulator diaphragm which would then warrant removing the accumulator to physically check the diaphragm hasn’t ruptured. Unfortunately there is no inbuilt test or software that allows for checking individual damper accumulator nitrogen charge, they simply don’t have pressure sensors. The single pressure sensor in the entire AHC/AVS system actually monitors the pump output and takes a snapshot reading during the end stages of the L to N raise cycle which are the values displayed in Techstream or the diagnostic reader in use.