It sounds like you have problem with the front or rear SAM module I would disconnect the battery and then locate the electrical connector and remove them to check for corrosion.
Also, check the fuses because the SAM units use many fuses to work the system. # 16, 14, 13, 12, 10, 4 ,2 ,1 and 7.
Here is a guide to help us get started:
Here are the SAM module locations and the wiring diagrams so you can see how the system works along with the fuse panel locations and identifications. You can follow this guide to check the wiring before you replace the SAM modules. This will need to be done by the dealer or a shop because they will need to be programmed.
Check out the diagrams (below).
Please let us know what you find. We are interested to see what it is.
Images (Click to enlarge)
Sunday, January 21st, 2018 AT 1:55 PM