Sakai SW800 Series, Shop Manual

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4-006
Precautions for Diagnosis of Electric Circuit
4. Precautions for Diagnosis of Electric Circuit
1. When disconnecting or connecting connectors or harnesses, cut the power supply.
2. Before making a diagnosis, check the connectors or harnesses for poor connection.
★
If a connector is at fault, check it by repeating connection and disconnection several
times.
3. Before proceeding to the next step, reconnect removed connectors or harnesses in place.
★
Care must be used for the controller circuit. If the power source is switched on with the
connector disconnected, this can cause an incorrect measurement.
4. When making a diagnosis of circuits (measurement of voltage, resistance, current, test for conti-
nuity, etc.), check to see if tester readings vary by shaking connectors or harnesses.
★ If readings vary, a possible cause is a poor connection of the circuit.
5. For voltage measurement, turn the starter switch ON. For resistance checking, let the switch stay
in the Off position.
★
If necessary to take a measurement of resistance by energizing relays or other units with
the starter switch ON, necessary instructions are given in the flow charts.