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Electrical Troubleshooting Tools

ELECTRICAL TROUBLESHOOTING TOOLS (TEST LIGHT)




The test light, as shown in figure, uses a 12V bulb. The two lead wires should be connected to probes.

The test light is used for simple voltage checks and in checking for short circuits.

CAUTION: When checking the engine control module (ECM), never use a bulb exceeding 3.4W.

ELECTRICAL TROUBLESHOOTING TOOLS (JUMPER WIRE)




The jumper wire is used for testing by shorting across switch terminals and ground connections.

CAUTION: Do not connect a jumper wire from the power source line to a body ground. Such a connection may cause damage to harnesses or electronic components.

VOLTMETER




The DC voltmeter measures circuit voltage. A voltmeter with a range of 15V or more is used by connecting the positive (+) probe (rod lead wire) to the point where voltage is to be measured, and the negative (-) probe (blank cad wire) to a body ground.

OHMMETER




The ohmmeter is used to measure the resistance between two points in a circuit and also to check for continuity and the diagnosis of short circuits.

CAUTION: Do not attempt to connect the ohmmeter to any circuit in which voltage is applied. Such a connection may damage the ohmmeter.