P- 2.0.7 Isolate "Watch Dog Output' - Fresenius Medical Care 2008K2 Troubleshooting Manual

P- 2.0.7 ISOLATE 'WATCH DOG OUTPUT'
IMPORTANT! Turn the machine OFF!
a)
b) Per the Figure below, locate IC2 at the top edge of the Power Logic Board.
c) Under IC2 are three resistors, top to bottom R8, R9 and R10.
d) TIGHTLY HOLD the meter lead at resistor #10 (R10) at the location shown in the Figure above.
e) Looking for more than 4.0 volts at least once,
METER
, turn the machine ON (fan running) and watch for thirty (30) seconds,!
f) TWO (2) possible scenarios:
1) IF (and ONLY if) NEVER, EVER more than 4.0 volts: Repeat procedure P- 2.0.7. If R10 still
NEVER goes to more than 4.0 volts see procedure number
2) IF more than 4.0 volts at least once! See parts A through C below:
A) Turn the machine off and swap in known good Power Logic Board.
B) Turn the machine on.
C) If System Initialization does reach 100% see procedure number
System Initialization does reach 100% the previous Power Logic board is bad!
Figure 131 – Power Logic Board/ R10
WITHOUT LOOKING AWAY FROM THE
2008K/K2 Troubleshooting Guide
P/N 507298 Rev. H
P- 2.0.8 (page 646).
P- 2.0.8 (page 646). If
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