Bosch SHI 4302 Troubleshooting Tips page 14

Page C-2
SHU/SHI/SHV Dishwasher Quick Check Chart
To check
/ ü ü ü ü Current through hot
ü ü ü ü Heater flow
/
switch Hi-
Limit
thermostat
o
(185 F)
HINT: The resistance of
heater is ≈ 11
thermostat is ≈ .3
switch is ≈ .4
flow switch resistance,
remove microswitch & close
its contacts.
HINT: The NTC and Hi-Limit
(185
changed as a unit. Must pull
out dishwasher and remove
or block up tub to replace it.
ü ü ü ü NTC
ü ü ü ü
(temperature
probe)
HINT: Make sure water in
sump has cooled to room
temperature before
measuring resistance.
ü ü ü ü Water level
ü ü ü ü
switch
ü ü ü ü Float switch
ü ü ü ü
st
1 Edition/Revision 0-A
Measure
wire into dishwasher –
should be 10.5-11 A
(amps).
Ω,
Hi-Limit
Ω
& flow
Ω.
To measure
o
F thermostat) are
At control module,
measure resistance
between two brown
wires at left of right
harness (≈ 55 kΩ at
room temperature
o
(72 F)).
After water fills, turn off
dishwasher and
measure (SHU/I
models) between white
rd
wire at left of 3
harness from left and
nd
2 blue wire from left of
th
4 harness from left (≈
.4 Ω).
Resistance between
white wire to water
valve and white wire
either at right of on/off
switch harness (SHU/I
th
models) or at left of 4
harness (SHV models)
(≈ 4Ω).
If yes
ü ü ü ü Heater/flow switch/Hi-
Limit thermostat are
OK.
HINT: Don't pull out
dishwasher and remove tub
for initial checking – only
when you're certain one of
these parts has failed.
HINT: Start test program
(SHU/I models) and skip
"draining" and "Aqua Sensor
Calibration" until water has
finished filling. When heater
comes on, measure current.
Skip "heating & circulating"
once you've measured
current to save time.
ü ü ü ü NTC probably is OK.
ü ü ü ü Water level switch is
OK.
HINT: For SHV models,
measure between white wire
st
at right of 1 harness & white
th
wire at left of 4 harness.
ü ü ü ü Float switch and water
valve probably are OK.
B
If no
Test each part, turn off
ü ü ü ü
dishwasher and
replace defective part.
HINT: Must pull out
dishwasher and remove or
tilt/block up tub to replace
parts. Bring all three parts
before disassembling
dishwasher and test each
part separately.
HINT: The Hi-Limit
o
thermostat (185 F) is a bi-
metal self-resetting
thermostat.
ü ü ü ü Turn off dishwasher
and replace NTC.
HINT: The NTC and Hi-Limit
o
(185 F thermostat) are
changed as a unit. Must pull
out dishwasher and remove
or block up tub to replace it.
ü ü ü ü Turn off dishwasher
and replace water
level switch.
HINT: Must pull out
dishwasher and remove left
side panel to access water
level switch.
ü ü ü ü Test float switch and
water valve, turn off
dishwasher and
replace whatever part
was defective.
Tuesday, May 11, 1999