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Fault Diagnosis




Fault Diagnosis

When diagnosing an electrical fault follow the steps below:
1. Read the circuit description appropriate to the reported fault to ensure a good understanding of circuit operation.
2. Study the power distribution, fuse details and earth distribution diagrams and identify other circuits which share fuses and/or earth points. Check whether these circuits operate correctly.
3. Using the photographs contained in the Connector Views, locate a point on the circuit (approximately half way between supply and earth) which is easily accessible.
4. Check that the pin out details of the connector are correct and that the correct signals exist at the correct terminals.
5. Using the marker pen supplied (or other suitable non- permanent marker pen) mark the parts of the circuit you have verified.
6. Continue to the next point on the circuit which is easiest to access and repeat the above.
7. Continue this approach until a fault is found rectify the fault and then verify that the circuit operates correctly.