Agilent Technologies 6890 Series, Service Manual, Page: 204 / 867

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Jun 2001
Inlets
Agilent 6890 Gas Chromatograph Service Manual
Pneumatics Control Module 270
Leak testing the PCM
4. Disconnect the ribbon cable for the module from the pneumatics board.
You may also have to remove the adjacent ribbon cable.
5. Use a Torx T-20 screwdriver to remove the screw from the top of the
module and slide the module out of the back of the GC.
6. Connect one end of the leak test ribbon cable (G1530-61370) to the ribbon
cable connector on the PCM and connect the other end to the appropriate
connector on the pneumatics board. Reconnect the gas supply and turn
on the main power switch. Set the pressure to 25 psi and the flow to 60
mL/min.
7. Lay the PCM on the lab bench and use an electronic leak detector to locate
the leaky component on the module.
Figure 270-3 Leak testing the
PCM
on the lab bench
8. If the leaky component is serviceable, such as a vent/inlet fitting (see the
diagram of serviceable parts, Figure 270-4), replace it. Otherwise, replace
the PCM.
Ribbon cable from leak test kit