Mazda 6 Service Manual: No.3 will not crank

No.2 mil illuminates

No.4 hard to start/long crank/erratic start/erratic crank

Other materials:

Mazda 6 Service Manual: Main fuse removal/installation
1. Disconnect the negative battery cable. 2. Remove the main fuse block cover. 3. Remove in the order indicated in the table. 4. Install in the reverse order of removal. Bolt Removal Note 1. Press and remove the tabs on the main fuse block at the positions indicated by the arrows. 2. L ...

Mazda 6 Service Manual: Engine control system operation inspection
Main Relay Operation Inspection Verify that the main relay clicks when the ignition switch is turned to ON position and off. If there is no operation sound, inspect the following. - Main relay (See RELAY INSPECTION.) - Harness and connector between ignition switch and main relay termi ...