JiffyPop

Just finished doing some upper and lower control arm replacements on my 08 LS600hL. Immediately after i finished the job I noticed the front end was extremely bouncy. I pressed down on the front end only to discover zero damping, just as if the struts were completely blown.

When changing the upper control arms I had to disconnect the damper adjusters to lower the shocks. I also had to turn the car on to turn the wheel while it was disconnected. I'm thinking something happened to the damper control system when the arms were replaced. I have techstream and can't find any faults with the suspension system other than a previous code for C1732 FL Dampern actuator circuit I'm assuming happened when I turned the car on to spin the wheel. The code is no longer there. I was also able to find a tech sheet and was able to test the resistance for the actuators and they all show good. I was even able to manually activate the steps in the damper motors so I know they are being controlled.

Any thoughts to What the issue may be? Is there a damper initilization process I need to do? I highly doubt that both struts would instantly fail during a repair. I know that with the ls430 there was a certain way to align the actuators. Anybody by chance have the service manual pages for ours?

Lynzoid

awwww. you should NEVER turn ign on with car off wheels.... next time use factory manual and sst.

JiffyPop

Well unfortunately that statement isn't true. The service manual clearly states when replacing an air strut to start the vehicle to pressurize the strut. Inspect for leaks, and if all is good, continue to put the wheel on.

After some further reading it is suggested to perform a height level offset adjustment. I'll try that and report any results.

Lynzoid

Keep in mind that the positions of the actuator shaft are from 'stiff' to 'very stiff'. even 'soft' setting is kinda 'feelable'.
also, if it can help, the logic of active sus is to stay on 'most hard' setting at low speeds (sharp maneuvering/parking) and to start fiddling with the actuators nearing 20+mph. before that 'most hard' is the setting regardless of user switch position.
try verifying the datalist of airsus to see weird stuff (big mm offset etc).
also, there isn't big link between air 'pillow' part and adjusting shock part. there is some logic going on there, but better to think of those as two separate systems.