Mazda 6 Service Manual: Troubleshooting index

On-board diagnostic function

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No. 1 one or more 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 i ...

Other materials:

Mazda 6 Service Manual: Intermittent concern troubleshooting
  Vibration Method 1. If malfunction occurs or becomes worse while driving on a rough road or when engine is vibrating, perform the steps below. Note There are several reasons vehicle or engine vibration could cause an electrical malfunction. Some of the things to check for are: ...

Mazda 6 Service Manual: Locking, Unlocking the Doors
NOTE The system may not operate if you are too close to the windows or door handles. If the key is left in the following areas and you leave the vehicle, the doors may be locked depending on the radio wave conditions even if the key is left in the vehicle. Around the dashboard ...