Jumper wire
Caution

Voltmeter
is used by connecting the positive (+) probe (red lead wire) to the point where voltage will be measured and the negative (-) probe (black lead wire) to a body ground.

Ohmmeter
Caution

Connectors
Precautions before weldingMazda 6 Service Manual: Filament inspection
1. Turn the ignition switch to ON position.
2. Turn the rear window defroster switch on.
Caution
Directly touching the rear window defroster filament with the lead
of the voltmeter will damage it. Wrap aluminum foil around the end of the
lead and test the filament by touching it with the ...
Mazda 6 Service Manual: Solenoid valve inspection
Resistance Inspection (On-Vehicle Inspection)
Caution
Water or foreign objects entering the connector can cause a poor
connection or corrosion. Be sure not to drop water or foreign objects on the
connector when disconnecting it.
1. Disconnect the negative battery cable.
2. Remove the ...