Troubleshooting Tests - Maytag W10393006 Service Manual

FOR SERVICE TECHNICIAN'S USE ONLY

TROUBLESHOOTING TESTS

IMPORTANT: The following procedures
may require the use of needle probes
to measure voltage. Failure to use needle
probes will damage the connectors.
TEST #1: CCU Power Check
This test checks for incoming and outgoing power
to and from the Cycle Control Unit (CCU). This test
assumes that proper voltage is present at the outlet.
1. Unplug dryer or disconnect power.
2. Check for appropriate line voltages at the
outlet: 240V AC (electric 2-phase), 208V AC
(electric 3-phase), or 120V AC (gas).
 If line voltage is present, go to step 3.
 If line voltage is not present, check for
tripped circuit breaker or blown household
fuse. If CB (circuit breaker) is not tripped,
have customer check with qualified
electrician.
3. Remove console to access the CCU
and User Interface (UI).
4. Plug in dryer or reconnect power.
P2 – USER INTERFACE (+5 V DC)
P2-1 BLK +5V DC
P2-2 WHT DATA
P2-3 WHT 5V GND
P8 – WATER VALVE/DOOR SWITCH
P8-5 BK/W MOTOR CENT. SW.
P8-4 TAN DOOR SWITCH
P8-3 WHT NEUTRAL
P8-2 G/Y CHASSIS GND
P8-1 BRN DRUM LIGHT
Heater Relay
(Gas & Elect.)
L1 – BLK (N.O.)
Heater – RED (COM)
Water Valve
(On Select Models)
L1 – BLU (N.O.)
Water Valve –
RED (COM)
Figure 2 - CCU Connectors & Pinouts
DO NOT REMOVE OR
P5 – +5V/+12V DC
P5-1 +5V DC
P5-2
P5-3 CIRCUIT GND
P5-4
P5-5
P5-6
P5-7
P5-8 +12V DC
P4/14-3 RED/R-W OUTLET THERMISTOR
P4/14-2 RED INLET THERMISTOR
P4/14-1 RED INLET THERMISTOR
P9
K2
K1
P8
DESTROY
5. CCU AC – With voltmeter set to AC,
connect black probe to CCU P8-3 (N) and
red probe to P9-2 (L1). (See Figure 2.)
 If 120V AC is present, go to step 6.
 If 120V AC is not present, perform TEST
#2: Supply Connections, page 10.
6. CCU +5V DC – Perform the following
voltage checks inside P5—DO NOT SHORT
PINS TOGETHER. With voltmeter set to DC,
connect black probe to CCU P5-3 (ground)
and red probe to P5-1 (+5V DC).
 If +5V DC is present, go to step 9.
 If +5V DC is not present, go to step 7.
7. Unplug dryer or disconnect power.
Unplug P4/P14 from the CCU. Plug in dryer
or reconnect power and repeat step 6.
 If +5V DC returns, one of the thermistors
has shorted. To diagnose thermistors,
see TEST #4a, page 15.
 If +5V DC is not present, go to step 8.
8. Unplug dryer or disconnect power.
Reconnect P4/P14 to the CCU and unplug
P2 from the CCU. Plug in dryer or reconnect
power and repeat step 6.
P9 – MOTOR/L1
P9-2
P9-1
P13 – MOISTURE SENSOR
P13-2 Y/R
P13-1 Y/R
P4 (ELECT.) / P14 (GAS) – THERMISTORS
P4/14-6 RED/R-W OUTLET THERMISTOR
P14-5
P14-4
Motor Relay
BLK L1
LT BLU MOTOR
MOISTURE SENSOR
MOISTURE SENSOR
BLK MODEL RTN (GAS MODEL)
BLK MODEL (GAS MODEL)
P13
P5-1
P5-3
3
P5-8
P2
P4 (Elect.)
= pin-1
P14 (Gas)
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