Remove the regulator handle clip using a rag as shown.

Inner handle removal/installation
Regulator handle installationMazda 6 Service Manual: Anchor Bracket
Anchor brackets for securing childrestraint systems are equipped in the vehicle.
Locate each anchor position using the illustration.
To install a child-restraint system, remove the head restraint. Always follow
the instruction manual accompanying the child-restraint system.
Anchor bracket loca ...
Mazda 6 Service Manual: No.8 brake system warning light stays on more than 4 seconds with ignition
switch on
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 co ...