Code List Selective Ride Control FX3:
12 Start of code sequence
13 Left Rear time out
14 Right Front time out
21 Left Front time out
22 Right Rear time out
23 Loss of vehicle speed signal
31 Left Front out of position
32 Right Front out of position
33 Left Rear out of position
34 Right Rear out of position
41 Selective Ride Control Switch short to Voltage
42 Selective Ride Control Switch open contacts
43 Selective Ride Control Switch open circuit

Can someone here explain these codes and would be fixes.

 

I think that is every code. My 89 showed the same thing when I bought it. I had all original shocks at 58000 miles and I knew at least one was totally bad. I bought a new set of shocks, replaced the known bad one and turned on the car to check the first shock. All codes imediately cleared. I understand that the fx3 computer can overload itself on occasion.

 

These would be, the shock operator gears most likely.

31 Left Front out of position
32 Right Front out of position
33 Left Rear out of position
34 Right Rear out of position

The other codes, I'm not sure?

 

Honestly I would try clearing all codes and see what comes back. Keep in mind, you can and will get a Service Ride Control light if you cycle the key to the on position 3 times without the car moving.

 

Hoping to get a response from someone who has actually trouble-shooted the FX3 system.

 

So, no one has trouble-shooted the FX3 system on a C4 ???

 

I believe this to be correct .... but if not someone will be sure to step in and correct me:
1) Upon start up the FX3 system attempts to have the 4 actuators turn the gears at the top of each shock from the softest setting to the firmest and then back again.
2) This must be accomplished within a set time frame or an error code is generated. (13,14,21,22)
3) The actuator must register being at the (for sake of discussion) full counter clockwise position at the end of the test or an error code is generated (31,32,33,34)

The best way to check for what is causing the error code is to remove the specific actuator (identified by the error code) from the top of the shock. the actuator has gears made of plastic and over time they get brittle and strip. They can be repaired by a 3rd party service. The shocks also have a gear on top made of pot metal (there are 2 different designs depending on year of the car) these brittle metal gears will over time break as well. Replacement gears are available along with the little pins that hold the metal gear to the shock rod.

Over the years I've replaced all 4 of my shocks and had 3 of the 4 actuators rebuilt at least once.

Code 42 is generated if the 3 position selector switch is not in one of the 3 positions detents when the test is being run.

The FX3 control module can also go out (though I've not heard of this happening) it located in the storage compartment behind the drivers seat (at least it is on my 95).

I hope that this is of some help.

The FSM in section 3G has about 25 pages of diagnostic and repair procedure for the FX3 system.