TKA 9110 UC Coffeemaker Training Program Bosch Dryer WTA35 WTL54

: Pdf Bosch Dryer Wta35-Wtl54 Bosch_Dryer_WTA35-WTL54 Bosch, Thermador, Gaggenau, Siemens

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Page Count: 5

1st Edition/Revision 2 (1/27/03)

50

WTA/WTL Service Tips

WTA/WTL Service Tips --

-- Test Program (1)

Test Program (1)

WTA 35 & WTL 54 dryers have test programs enabling them to self-

diagnose problems, including listing the last fault code.

To enter/exit test program for WTA 35 & WTL 54 dryers:

♦Rotate Auto-cycle and Timed cycle knobs to Off position.

♦Push and hold Start and Delicate buttons at the same time, then turn dryer on by pushing On/Off button. After pushing

On/Off button, keep holding Start and Delicate buttons until Start light flashes rapidly. Dryer is now in the test program.

♦Lights will flash for drying faults -- fault shown will be the last fault code on the dryer (see fault chart on next page).

♦When test program has been entered:

♦Start light flashes rapidly.

♦Select individual parts to test by rotating Auto-cycle knob as shown on next page.

♦Don’t rotate Auto-cycle knob or push any button while individual tests are being run (so tests won’t stop).

♦Once part to test has been selected, start test by pushing Start button. Start light will stay on continually while tests

are running. Push Start button again to end any test. Tests have finished once Start light flashes rapidly again.

♦To exit test program, push Start button (while Start light flashes rapidly).

NOTE:Fault displayed

will be 1st fault that

occurred since last time

dryer was turned on.

Timed cycle

knob Auto-cycle

knob

1st Edition/Revision 2 (1/27/03)

51

WTA/WTL Service Tips

WTA/WTL Service Tips --

-- Test Program (2)

Test Program (2)

Test parts individually as follows:

♦Indicating lights & digital display – To start test, rotate Auto-cycle knob to Regular/Cotton Extra Dry, then push Start button. To

end test, rotate Auto-cycle knob out of Regular/Cotton Extra Dry position.

Cycle buttons & selector switches – To start test, rotate Auto-cycle knob to Regular/Cotton Very Dry, then push Start button. To

end test, push Start button again (since test doesn’t end).

♦Pump, motor, heater & NTC’s –To start test, rotate Auto-cycle knob to Regular/Cotton Regular Dry, then push Start button. Test

ends automatically.

♦Sensor conductance – To start test, rotate Auto-cycle knob to Regular/Cotton Light Dry, then push Start button. To end test, push

Start button again (since test doesn’t end).

Fault Possible Causes Flashing Lights Digital Display

Drying time too long  Control module failed.

 Moisture sensor(s) failed.

 Hi-Limit (“overheat”) thermostat tripped and failed to

reset.

 Water level switch failed (WTL 54 only).

 Supply voltage too low.

Overheating  Control module failed.

 Heater failed.

R3 NTC failed (short or open circuited)  NTC # R3 failed.

R2 NTC failed (short or open circuited)  NTC # R2 failed.

Condensed water not pumped out

(WTL 54 condensation models only)

 Pump failed. E1

A

nti-Crease/

End

Extra Dry

Damp Dry

Regular Dry

1st Edition/Revision 2 (1/27/03)

52

WTA/WTL Service Tips

WTA/WTL Service Tips --

-- Test Program (3)

Test Program (3)

SELECTOR

KNOB

KNOB PROGRAMS KNOB

POSITION

LIGHTS

Drying Damp

Dry

Regular

Dry

Extra

Dry

Anti-

Crease/End

Off

Regular/Cotton Extra Dry On

Regular/Cotton Very Dry On

Regular/Cotton Regular Dry On

Regular/Cotton Light Dry On

Regular/Cotton Econo Dry On

Regular/Cotton Damp Dry On On

Permanent Press Econo Dry On On

Permanent Press Light Dry On On

Permanent Press Regular Dry On On

Permanent Press Very Dry On On

Program

Selector

Knob

NOTE: Red

Regular/

Cotton Very

Dry lights stay

lit during this

test no matter

what program

selector

position is

chosen – no

other Regular/

Cotton or

Permanent

Press lights

comes on.

Permanent Press Extra Dry On On

Timed cycle Heated Dry On On

Timed cycle On On

Timed cycle On On

Timed Cycle

Knob

NOTE:

program

selector knob

MUST be

straight up for

tests to run.

Timed cycle Air Fluff On On

NOTES:

• Pushing "START" button

after test has ended will

repeat it.

• Door can be opened (if

desired) during this test.

•Delicates, End of Cycle

Signal and Cycle Time

Minutes lights stay lit

whenever button underneath

them is pushed and held.

• Digital display does not

come on during this test.

Cycle Buttons &

Selector

Switches Test

Chart

1st Edition/Revision 2 (1/27/03)

53

WTA/WTL Service Tips

WTA/WTL Service Tips --

-- Test Program (4)

Test Program (4)

Pump, motor, heater & NTC’s Test Sequence Chart

TEST ORDER & TIME (SECONDS) NOTES

START 15 5 2 5 29 END

PART

TESTED

3 5 5 2 5 1 5 1 5 1 5 1 5

Pump START

OF

TEST

END

OF

TEST

For WTL 54

condensation

dryer only

Motor –

right

rotation

Motor –

off

Motor –

left

rotation

During 29

second drum

reversing cycle,

drum runs for 5

seconds on / 1

second off –

check drum

rotation with

door open.

Heater

(E2)

Feel for heat

with door open.

Heater

(E3)

Feel for heat

with door open.

NOTES:

• Test ends

automatically.

Pushing Start

button after test

has ended will

repeat it.

• Opening door

stops test –

closing door

resumes test.

To check if

drum is turning

and if heat is

coming out of

drum, run test

with door open

by tripping door

latch (by gently

pushing it with a

screwdriver).

To exit test program (from any test), turn unit off by pressing "ON/OFF" button.

1st Edition/Revision 2 (1/27/03)

54

WTA/WTL Service Tips

WTA/WTL Service Tips --

-- Test Program (5)

Test Program (5)

Sensor Conductance Test

HINTS:

• Tests can be run with door closed. Opening door during testing stops the test.

• To run 2nd test with sensors and drum connected, remove top panel and connect jumper

to copper braids (for two "brushes" touching outside of drum).

•Drum must be empty during these tests – damp clothes in drum will give wrong results.

• Lights won't flash during this test.

To exit test program (from

any test), turn unit off by

pressing "ON/OFF" button.

LIGHTS SHOWING CONDUCTANCE OF MOISTURE SENSORS

Test "Drying" light "Damp Dry" light Comments

No fault

Drum empty –sensors and drum not connected

Fault – short circuit

No fault

Drum empty – with sensors and drum connected

HINT: Remove top panel and jumper between copper

braids (to "brushes" touching outside of drum). Fault – open circuit or

circuit resistance is too high

Drying

Drying

Damp Dry

Damp Dry

Damp Dry

Damp Dry

Drying

Drying

HINT:Using the test program can cut down repair

times & eliminate repeat calls from misdiagnosing

problems. The pump, motor, heaters, NTC’s and

moisture sensor conductance tests are more helpful

than the buttons, knobs, lights and display tests.