1. Remove the drive belt. (See DRIVE BELT REPLACEMENT.)
2. Verify that the drive belt auto tensioner moves smoothly in the operational direction.

3. Turn the drive belt auto tensioner pulley by hand and verify that it rotates smoothly.
4. Install the drive belt. (See DRIVE BELT REPLACEMENT.)
Drive belt replacement
Valve clearanceMazda 6 Service Manual: Dsc hu/cm removal/installation
Caution
When replacing the DSC HU/CM, configuration procedure must be done
before removing the DSC HU/CM. If configuration is not completed before
removing the DSC HU/CM, DTC B2477 will be detected.
Do not drop the DSC HU/CM. Replace it if it is subjected to an
impact.
1. Configura ...
Mazda 6 Service Manual: No. 2 all on-board diagnostic functions inoperative
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 malfunctions. If there
is a problem, check to make sure connectors, terminals and wir ...