1. Inspect the dust boot on the drive shaft for cracks, damage, leaking grease, and looseness in the boot band.

2. Inspect the drive shaft for bends, cracks, and wear in the joint or splines.
Joint shaft disassembly/assembly
Drive shaft removal/installationMazda 6 Service Manual: Air intake actuator inspection
1. Connect battery positive voltage to terminal D or F and ground to terminal
F or D of the air intake actuator.
2. Verify that the air intake actuator operates as shown below.
If not as specified, replace the air intake actuator.
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Mazda 6 Service Manual: Stopping The Smart Brake Support (SBS) System Operation
The Smart Brake Support (SBS) system can be temporarily deactivated.
When the Smart Brake Support (SBS) system is turned off, the Smart Brake Support
(SBS) OFF indicator light turns on.
When the engine is restarted, the system becomes operational.
NOTE
If the Smart Brake Support (SBS) system ...