Sakai SW352, Service Manual

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4-006
Precautions for Fault Diagnosis of Electric System
4. Precautions for Fault Diagnosis of Electric System
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.
★ Check connectors by repeating connection and disconnection practices several times.
3. Before proceeding to the subsequent step, reconnect removed connectors or harnesses in place.
★
If the power source is connected with the connectors disconnected, unusual indication
will be given.
4. When making diagnosis of circuit troubles (while performing measurement of voltage, resistance
and current or continuity test, etc.), check to see if the tester readings vary by shaking connectors
or harneses.
★ 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, set the switch in
the Off position.
★ If necessary to take a measurement of resistance by energizing relays or other units
with the starter switch ON, the instruction to do so is given under the checking
instruction box (
□ ) in the flow chart.