Vehicles have various electrical parts. To protect the parts from excessive current generated when welding, be sure to perform the following procedure.
1. Turn the ignition switch to the LOCK position.
2. Disconnect the battery cables.

3. Securely connect the welding machine to the ground near the welding area.
4. Cover the peripheral parts of the welding area to protect them from weld spatter.

Electrical troubleshooting tools
Jacking positions ,vehicle lift (2 supports),safety stands (rigid rack)
positionsMazda 6 Service Manual: Intermittent concern troubleshooting
Vibration Method
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 why vehicle or engine vibration could
cause an electrical malfunction. Some of the things to check for:
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Mazda 6 Service Manual: Generator removal/installation
Warning
When the battery cables are connected, touching the vehicle body with
generator terminal B will generate sparks. This can cause personal injury, fire,
and damage to the electrical components. Always disconnect the battery negative
cables before performing the following operation.
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