Model 4700 Maintenance Manual
Section 7. Component Procedures
Electrical Components
Wiring and Harness Connectors General Repair Procedures
Wiring and Harness Connectors •
Use the appropriate tools to remove and insert terminations at each connector.
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Remove damaged terminations and discard. Never reuse a termination from a wire.
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Do not cut away a terminal lug and reuse the wire strands that were crimped into the original lug.
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When stripping wire, use new wire strands for new terminations. Use a new wire with extra length to allow for cutting and stripping of the ends to install new terminations.
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Use a new wire that is the same gauge (typically 18 gauge AWG), size, type, and color as the wire it is replacing.
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Use a hand stripper capable of stripping by wire gauge number. Use care not to nick or cut any of the wire strands. Discard and replace a wire with damaged strands. Insert the wire strands the correct length into termination before crimping.
See “Electrical Troubleshooting” on page 5-2. Whenever working on the lift truck, use care around wiring harnesses. •
Carefully connect and disconnect all connections.
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Do not pry connectors apart with unspecified tools.
There should be a wire marker at each termination. If the marker is missing or unreadable, remark the wire to allow easier identification. NOTE: It is normal to find unused connectors for uninstalled options that have had heat shrink applied over them and have been strapped to the harness.
Repair
Use correct electrostatic discharge precautions. See “Static Precautions” on page 2-7. When pulling a wire out through a bundle, cut off the pin or socket so it will not snag. When replacing wires, in some cases you will be able to tape or solder one end of a new wire to one end of the failed wire. Then you can pull the old wire out of the bundle and pull the new wire into the bundle, all at the same time. Be sure to disconnect the old wire from the new wire. In other cases, it is easier to secure a new wire to the outside of the existing wire bundle with straps of an appropriate size. The failed wire can be left in the bundle, or can be pulled by one end to remove it from the bundle. When replacing wires, follow these guidelines:
Publication 1160093, Issued: 20 May 2013
Soldering Procedures To prevent damage from excessive heat when soldering small components in assemblies, follow these guidelines. Make sure the soldering tip is clean. A dirty tip does not transfer heat well and encourages long dwell time and greater pressure. Apply light pressure on the terminal. •
Flux: rosin base
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Solder: 60/40 rosin core or equivalent
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Solder Iron: 55 watt max
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Tip Size: 0.118 in. (3 mm) diameter by 1.182 in. (30 mm) long screwdriver tip
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Tip Temperature: 500°F (260°C) max
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Terminal Contact Time: 6 seconds max
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After soldering, clean the terminals with a brush dampened with an alcohol-based cleaner (P/N 990-600/FOF). Do not allow cleaner to seep into switches or potentiometers.
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