NOTE: Prior to reassembling, clean all the parts in solvent, dry them, and apply MTF to all contact surfaces.

HandsFreeLink System Description
HandsFreeLink Control Unit Connector for Inputs and Outputs
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Regulator Valve Body Disassembly, Inspection, and Reassembly (A/T)
Clean all parts thoroughly in solvent, and dry them with compressed air.
Blow out all passages except the air check valve filter.
Inspect the regulator valve body for scoring and ...