OHAUS T71P, Service Manual

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CHAPTER 2 TROUBLESHOOTING
2.2.1 Diagnosis
TABLE 2-1. DIAGNOSTIC GUIDE
Symptom Possible Cause(s) Remedy
Unit will not turn on Power cord not plugged in or
properly connected.
Power outlet not supplying
electricity.
Battery discharged.
Other failure.
Check power cord connections. Make
sure power cord is plugged in properly
into the power outlet.
Check power source.
Replace disposable batteries
or recharge NiMH Pack.
Check cable connections;
replace PCB.
Battery symbol blank Battery discharged. Replace disposable batteries
or recharge NiMH Pack.
Cannot zero the
Scale, or will not
zero when turned on Load on Scale exceeds
allowable limits.
Load on Scale is not stable.
Load Cell damage.
Remove load on Scale.
Wait for load to become stable.
Replace Load Cell.
Poor accuracy Improper calibration
Unstable environment
Perform calibration.
Move scale to suitable location.
Unable to calibrate Unstable environment
Incorrect calibration mass
Lock Calibration Menu set to On.
LFT menu set to On.
Main PCB failure
Move the scale to suitable location.
Use correct calibration mass.
Set Lock Calibration Menu to Off.
Set LFT menu to Off.
Replace Main PCB.
Cannot display
weight in desired
weighing unit Unit not set to On. Enable unit in the Units Menu.
Problems with
Display (missing
characters, partial
display, erratic or
unstable display) Display PCB failure Check Display PCB Cable.
Replace Display PCB.
Replace Main PCB.
Cannot change
menu settings Menu has been locked. Set selected menu to Off in the Lock
Menu.
Lockout Switch on the circuit board may
need to be set to the Off position.
(See Figure 1-1.)
Does not retain
correct time Real time clock battery failure Replace real time clock battery.
(See Figure 1-3.)
7000 Series T71 Indicators Service Manual 2-3 Ohaus Corporation www.ohaus.com