Ohaus Indicator T51P

Unplug the Indicator from the AC Adapter

Remove the four screws from the Bottom Housing

Carefully separate the Top Housing and Bottom Housing

Pull all cable connectors from their plugs on the Main PCB

Remove cable-leads from Alternate Load Cell Connector J4 if connected

Remove hex screws connecting the RS232 Interface port to the Bottom Housing on the T51P

Turn the Indicator OFF and disconnect the AC Adapter or power cord

Reconnect the AC Adapter or power cord to the Indicator

Check to ensure that the Indicator retained calibration settings

Document any discrepancies found during the test

Confirm all connections are secure after the test

Verify communication parameters match between the Indicator and the external device

Press the Print/Units button on the Indicator

Check if printing occurs on the external printer or computer

If printing fails, describe the issue

Housing Separation and Cable Disconnection

Separate the Top and Bottom Housing (Follow steps 1 – 3 in Section 3.2.1.)

Disconnect the plastic ribbon cable from the Membrane Switch to the Display PCB’s Keypad Connector

Membrane Switch Removal and Cleaning

Lift up the defective Membrane Switch and gently peel it off the Upper Housing

Clean the Top Housing Membrane Switch area, removing all traces of adhesive

New Membrane Switch Installation

Remove the protective backing from the new Membrane Switch

Position the new Membrane Switch on the Top Cover using a rolling motion

Unplug the AC Adapter before cleaning.

Has the Indicator been moved from a different temperature area?

Clean the Indicator based on the model

Ensure no chemical cleaners or solvents are used.

Check the Power Cord for broken or damaged insulation.

Make a visual inspection for faulty connectors, wiring, and loose hardware.