The refrigerant specifications are indicated on a label attached to the inside of the engine compartment. Check the label before refilling the refrigerant. If the wrong type of refrigerant is used, it could result in a serious malfunction of the air conditioner.
For details, consult an Authorized Mazda Dealer.

Vent OperationMazda 6 Owners Manual: No.1 air bag system warning light does not illuminate
Diagnostic Procedure
When performing an asterisked (*) troubleshooting inspection, shake the
wiring harness and connectors while doing the inspection to discover whether
poor contact points are the cause of any intermittent malfunction. If there
is a problem, check to make sure connec ...
Mazda 6 Owners Manual: Dual proportioning valve replacement (without abs)
1. Remove in the order indicated in the table.
2. Install in the reverse order of removal.
Dual Proportioning Valve Installation Note
Install the dual proportioning valve so that the R mark faces the left side
of the vehicle.
...