A2 Power Pwb Parts List, Layout And Schematic - ConMed Hyfrecator 2000 Service Manual

Monitor-generated Fault Codes, continued
Fault Code
-9
-A
-B
-C
-D
-E
-F
No Fault Code failure.
If unit powers up or "dies" silent with no displays, verify +5M and +5C are correct, verify microcontroller
clocks per -C fault, verify /MCLR both microcontroller pins 1 at +5. Replace A1U1 then A1U2.
Meaning
PSET & LED scan rate incorrect.
PSET byte inconsistent with
LED drive.
Monitor process error.
Monitor interrupt error.
Invalid PSET value on PSET bus.
VMODE.M out of range on
activation.
Tone not detected during
activation.
Possible Remedies
Check LED1S & LED10S with an
oscilloscope. Verify 1S high for 4 msec,
then both low, then 10s high 4 msec,
then both low in continuous cycle. Verify
both swing 0 to +5V . Replace A1U1 or
A1U2.
Verify normal sequence of LED bars
during POST. Enter Service Pr mode,
verify PSET bus and LED drive lines
swing 0 to +5 as power is adjusted.
Verify clocks at 4.00 MHz both
microcontrollers pin 10 (use 10K probe
isolator resistor). If defective, replace Y1
or Y2, otherwise replace A1U1 or A1U2.
Replace A1U2.
Replace A1U2.
Troubleshoot same as -9.
Troubleshoot same as -8.
Replace A1U2.
In Service Pr mode, verify complaint by
ear. Attempt volume adjust. If tone is
heard, verify TONEMON > 0.1V
during activation, < 0.3V idle. If no
tone, verify /TONE 0-5V about 1 KHz.
If correct, verify 12Vpp tone signal at
A2U1-5, 10Vpp at A2Q1-E at max
volume. Check LS1 dc continuity, R11.
2000
A-3