Climate Control unit won't program

[1999V70XCinPA]

Son's car. Blower worked (past tense) but could not direct the air or select temperature. Took the car to the local Volvo dealer. They literally had the car for 8 weeks. They replaced the climate flaps then could not get the control unit to program. They fried three of them.Thought it was a wiring issue. Overlaid some wires. Ended up removing the entire dashboard to check connections. Can't get the unit to program. After 8 weeks, are giving up. No charge. However, they can't get the climate system to work. Anyone have ideas?