With DSC
1. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
2. Disconnect the steering angle sensor connector.
3. Connect battery positive voltage to terminal A and ground to terminal F of the steering angle sensor.
4. Turn the steering wheel to the right and left, and verify that the voltage and pulses at the terminals are as shown in the figure.

Combination switch disassembly/assembly
Light switch removal/installationMazda 6 Service Manual: Knock sensor inspection
Note
Perform the following test only when directed.
Resistance Inspection
1. Turn the ignition switch to LOCK.
2. Disconnect the knock sensor connector.
3. Measure the resistance between the knock sensor terminals A and B using an
ohmmeter.
If not as specified, replace the knock sens ...
Mazda 6 Service Manual: Service cautions
HANDLING INSUFFICIENT REFRIGERANT LEVEL
If an insufficient refrigerant level is detected at troubleshooting,
do not charge (add) the refrigerant. Because an accurate amount of
refrigerant cannot be determined from the pressure indicated on the manifold
gauge, never charge the refrigeran ...