MPR
E-S
CAN
PROBLEM ANALYSIS
3.2 Trouble Shooting Chart
SYMPTOM
POSSIBLE CAUSE
No display, failsafe LED off.
No display, backlighting
Fuse blown.
Power supply failure, check 15vdc and 5vdc.
No display and failsafe LED on.
Display failure.
Video cable failure.
Display on but is garbled
CPU card failing.
Buttons do not respond properly.
Connector from overlay to I/O board not, or
improperly mated with J5.
Front panel overlay defective.
Defective I/O board (keyboard section).
E-Scan does not appear to take calibration
Replace CPU card.
“
NO TEMP. VOLTAGE”
flashing on
display
If voltage between TB1-3 and TB1-10 on the
IB is less than 0.2 volt and the process
temperature is above 25° C, check 2.5 volt
regulator VR-1 in the head.
Sensing head failed.
I/O card failed.
“NO MEAS. VOLTAGE”
flashing on
display
If positive voltage does not exist between
TB1-12 and TB1-3 on the IB, check for
process flow across prism.
Sensing head failed.
I/O card failed.
Measurement incorrect.
Check display for
O
,
U
, or
T
indicators.
Check for large digital offset value.
Rezero using analog zero (in software).
Rezero head using zero pot in sensing head.
“NO LAMP VOLTAGE”
flashing on
display
Sensing head failed.
Check for AGC voltage on LED.
Preamp card failed.
I/O card failed.
3-2