F355 Shock Motor Manual Settings?

You already did a lot ...
When you drove the motors directly on their connector, have you checked that the Hall effect sensors (2 per motor) deliver a square signal while the motor is turning. If 1 sensor over the 8 is bad you will get the light. The minimum set-up to check each sensor is to connect the pin D to a +5V source, and each sensor output (pins E & F) to the same +5V source through a resistor (a few kOhm). Then with the motor turning slowly, you should see, with a simple voltmeter, the voltage on the Hall sensors outputs swinging between +5V and 0V.

Other possibilities are the acceleration sensors at the front of the car which may be bad or experienced a connexion problem ...

If you want to use the car with the ECU non operative, I would suggest you set the 4 shocks at # 60° from the softest position. That is close enough to the error setting (actually 55°) when the ECU is able to drive each motor but not to adjust ths suspension according to the driving conditions (see page F26 of the WSM)

 

If you can PM me your phone number, I can help you preset the dampers. I have run dyno sheets on the stock shocks many times.


Jay

 

Most likely a bad actuator. I had the light, and could not find anything wrong with any of the actuators, and went through all the checks. I ended up swapping the left rear (just decided to start there) and "bingo" I have never had a return of the suspension light...so I found the bad one.

 

Great if you have a portable scope ... don't forget the pull-up resistors on the sensors output.
I agree with Hugh, it is sometimes not so easy to identify a bad actuator. I had the case on my car. One actuator was starting to seize and the only difference with the others is that it was just a bit slow.
I don't know which direction is soft on the damper but it shouldn't be that difficult to find it. According to the WSM the difference is discernable only in the expansion characteristic of the shock. Compression is very much less dependent of the setting. Between full soft and full stiff you should feel the difference.
If you have any doubt, I would say that 45° is OK. That is close to the soft setting of the ECU.

 

They are both behind the front bumper, in the middle of the front face of the car. You have to remove the bumper.
I doubt that, even if they are at fault, it would prevent the ECU to complete the self test and actuate each motor to CW end-stop and to CCW end-stop.

 

From the fog lamp access plates? I don't think so. May be from the front undertray but I am not sure. I never tried to access them and can't remember if they are visible with the tray removed.

Have you checked that both connectors are well connected to the ECU? Mainly connector B which is dedicated to the shocks motors. Have you open the ECU to look at any sign of failure? It can probably fail but the symptoms look strange.