If you can hear the motor but no seat motion it is either the plastic drive gear in the gearbox on the motor or the lever assembly on the seat frame, the most common failure is the gear. It is all part of the seat module assembly. To replace it you disable the airbag system by pulling the fuse for the SIR system. Then you disconnect and remove the front seat. Remove the seat cushion by freeing the retainers. Next you unbolt the seat frame from the power module. Reverse the process to install the new one.
You might want to look into a salvage yard part first. I have not replaced one on a DTS but one for a CTS was over $400.00 and that was a discounted price. I do not know of anyone other than used or dealer for the part.
Seat Adjuster - GM (25869500) DTS W 8 way power. $505.99, but it is listed as discontinued by GM. I would still try the dealer first.
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Friday, February 16th, 2018 AT 8:43 PM