T- 4.0.4 Isolate Ntc #2 Connections - Fresenius Medical Care 2008K2 Troubleshooting Manual

T- 4.0.4 ISOLATE NTC #2 CONNECTIONS

Turn the machine OFF!!
a)
b) Per the Figure right, place the
TWO-RESISTOR
plug, from the
st
SET 1
, into the distribution board
position from the left, "CON-NTC".
Set your volt meter to measure resistance (Ω)!
c)
ENSURE the black lead remains attached to chassis ground (see
d)
page 4)!
e) Per Figure 51 below, measure at the solder side of SENSOR BOARD'S 'X2' connector at pin 13 (bottom
row, 7 pins from the rear of machine).
f) Figure right, reading the meter's numeric AND
units display, TWO (2) possible scenarios:
IF (and ONLY if) LESS THAN 300 Ω (0.300 KΩ): ENSURING the machine was OFF before
1)
measuring AND assuming all procedures were performed correctly the mother board may be bad.
2) IF more than 300 Ω: See parts a THROUGH d below:
a) ENSURE the machine was OFF prior to the measurement!
b) ENSURE the
distribution board positon from the left, "CON-NTC"! If not, repeat procedure number
(page 291).
c) ENSURE the meter was set to measure resistance (Ω) AND its go=round lead is at chassis! If
not, repeat procedure number
d) TWO (2) possible bad components: 1) Sensor Board* cable OR; 2) Distribution board. *NOTE:
The Sensor Board cable can be checked! NOTE that one (1) NTC #2 connection will be checked
and proceed to
274 Ω
Figure 51 – NTC #2 Checks
274 Ω
TWO-RESISTOR SET
plug, from the
T- 4.0.4
page 524
, SECTION 17- CHECKING THE SENSOR BOARD
2008K/K2 Troubleshooting Guide
P/N 507298 Rev. H
(page 291).
Figure 2,
, is placed properly in the
T- 4.0.4
CABLE.
st
1
Page 291