P- 1.0.4 Pin 4 Between 4.0 And 6.0 Volts/Isolate The Power Button; P- 1.0.5 Power Button Okay/Isolate Power Logic Board - Fresenius Medical Care 2008K2 Troubleshooting Manual

P- 1.0.4 PIN 4 BETWEEN 4.0 AND 6.0 VOLTS / ISOLATE THE POWER BUTTON
a) Continuing to measure at the Switch Matrix Cable's,
(3) times.
b) Does voltage drop to LESS THAN 0.5 volts WHILE THE BUTTON IS PRESSED?
Yes Drops to LESS THAN 0.5 volts! The Power button is okay! See procedure number
(page 631).
No DOES NOT drop to less than 0.5 volts! Five (5) possible bad components. One at a time, referring
to the Component List below, swap in each then, in between, press the Power button to see if the
machine turns on indicating the last component swapped in is the problem.
Component List: 1) 24 pin Front Panel Data cable*; 2) Front Panel (Power button)*; 3) Front Panel
Interface Board*; 4) Power Logic board (card cage, first board from the left); 5) Motherboard*.
* To LOCATE these components refer to Figure 121 (page 629).
P- 1.0.5 POWER BUTTON OKAY / ISOLATE POWER LOGIC BOARD
a) Unplug the machine then plug it back in but
b) Per the Figure below, locate the Power Logic Board's 20-pin X2 ribbon cable at the front, top edge of the
board nearest the screen.
c) Measure at the rear side of the X2 cable at pin 3 (bottom row, second pin from the rear of the machine).
TWO (2) possible scenarios:
1) IF (and ONLY if) MORE THAN 6.0 volts: See procedure number
2) IF LESS THAN 6.0 volts: Proceed to
DO NOT
page 633,
Figure 123 – Power Logic Board / X2 pin 3
2008K/K2 Troubleshooting Guide
P/N 507298 Rev. H
pin 4
, press and release the Power button three
press the Power button yet!
P- 1.0.6
procedure number P-
P- 1.0.5
(page 632).
1.0.9.
Page 631