Mazda 6 Service Manual: No.25 a/c is not cut off under wide open throttle conditions

No.24 a/c is always on or a/c compressor runs continuously

No.26 exhaust sulphur smell

Other materials:

Mazda 6 Service Manual: Engine Start Function When Key Battery is Dead
CAUTION When starting the engine by holding the transmitter over the push button start due to a dead key battery or a malfunctioning key, be careful not to allow the following, otherwise the signal from the key will not be received correctly and the engine may not start. Metal parts of ot ...

Mazda 6 Service Manual: Antilock Brake System (ABS)
The ABS control unit continuously monitors the speed of each wheel. If one wheel is about to lock up, the ABS responds by automatically releasing and reapplying that wheel's brake. The driver will feel a slight vibration in the brake pedal and may hear a chattering noise from the brake system ...