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Intermittent And Poor Connections
Most intermittent problems are caused by faulty electrical connections or wiring. A sticking relay or solenoid can also be a problem. When diagnosing intermittent problems, check the following items:
1. Poor mating of connector halves.
2. Terminals not fully seated in the connector body (terminal backed out).
3. Dirt or corrosion on the terminals. The terminals must be clean and free of any foreign material.
4. Improperly formed or damaged terminals.
All connector terminals in problem circuits should be checked carefully to ensure good contact tension (Figure 1). Use a corresponding mating terminal to check for proper tension.
5. Poor terminal to wire connection.
Examples of this are poor crimps, poor solder joints, crimping over wire insulation rather than the wire itself and corrosion in the wire to terminal contact area (Figure 1).
6. Wire insulation which is rubbed through, Causing an intermittent short as the exposed area touches other wiring or parts of the vehicle.
7. Wiring that is broken inside the insulation.
8. Corroded wiring inside the insulation.
Both the conductor and insulator must be free of any corrosive damage to ensure good conductivity.
Upon customer complaint for the symptoms outlined, perform the specified repairs.
No specific parts apply to these inspections and repairs. Individual connectors may be needed.
Perform the diagnostic procedures and repairs outlined in the following pages for troubleshooting and repair of poor connections.
CAUTION: 1. Use a high impedance (10 megohms or higher) digital multimeter for troubleshooting.
2. When disconnecting a connector, pull on the connector halves. Do not pull on the wires to the connector.
3. Gold-plated terminals must not be mated with tin-plated terminals.