Volvo Repair: Volvo S80 ABS system, volvo s80, lifetime warranties

Question
Hello Roger, I have a 99 S80, and recently I had been getting several messages and alert lights on. The series would start with CHECK ENG/ABS/BRAKE and the STC lights on, the message would be
ABS system failure, stop car ASAP. The problem had gotten as bad as one day getting all of those warnings at a traffic signal, and then when I went to turn at the light, the car would shudder, and seemed to want to stop. I noticed the speedometer was not working for the short drive to the parking lot. I shut the car down, and later when I went to leave, all of the lights would be off, except the CHECK ENG light, and the message window had Transmission SYS SRVC REQRD. Other times the messages in the window would be STC system reqrd, or Power Steering Sys Reqrd. I had a local, dependable, independent mech take a look, and he cleared the codes. The codes his machine found were PO722, PO1618, PO1633. The messages and lights came back on 3 days later. (this was the 3rd or 4th time for this) After restarting the car, just CHK ENG light and Transmission Srvc Reqrd messages were on.

2 days later I went to the Volvo dealer for the recall on the Elec Throttle Sys software upgrade. Had that completed, and they ran the car on their diagnostics, came back with
"TCM FAULT 001F, ABS FAULT 0093, 0091
Test Circuits Fault in Control Module".
They tell me the module is 714$, and total cost of repair is 950$. Which module would I actually need to replace, and any chance I should go out seeking this part myself and having the independent shop do the work? I know if it's the ABS module, would need the special torx wrench to remove the 4 bolts. Have seen internet sites offering refurbished ABS modules with lifetime warranties. Too risky? I value your response Roger, thank you. Currently the lights are all still out after 2 days, don't know how long that will last.  

Answer
Dave, We use those ABS control units and they work well.  The dealer is ripping you off.  If anything, I think that module is about 500 bucks with 1.5 hours labor.  yes you need that special socket and patience.  The S80 is not a user friendly car.  Roger