Volvo C30 2007 Service And Repair Manual page 537

Fig. 154: Identifying Shield And Clips
Courtesy of VOLVO CARS CORPORATION
Remove the expansion tank cap.
Raise the vehicle.
Remove the shield under the vehicle. It is secured with 7 clips. See the illustration.
Install a hose on the nipple at the radiator.
Feed the hose down to a container.
Open the nipple. Drain off the engine coolant.
REMOVAL
REMOVING THE ENGINE COOLANT HEATER
2012 Volvo C30 T-5
HVAC Climate Units - Removal, Replacement And Installation