Troubleshooting guide

PAGE 17
FOR SERVICE TECHNICIAN’S USE ONLY
DO NOT REMOVE OR DESTROY
4. Check P14-1 and P14-2 to dryer cabinet
ground. If either pin indicates continuity
to ground (short), replace wiring harness;
otherwise, proceed to step 5.
5. If the preceding steps did not correct the
problem, replace the CCU.
TEST #4b: Thermal Fuse
ELECTRIC DRYER: The thermal fuse is wired
in series with the dryer drive motor.
GAS DRYER: The thermal fuse is wired
in series with the dryer gas valve.
ALL DRYERS:
1. Unplug dryer or disconnect power.
2. Access the thermal fuse by removing
the front panel. See Dryer Disassembly
Instructions, page 22.
3. Using an ohmmeter, check the continuity
across the thermal fuse.
If the ohmmeter indicates an open circuit,
replace the thermal fuse.
TEST #4c: Thermal Cut-Off
If the dryer does not produce heat, check the
status of the thermal cut-off.
1. Unplug dryer or disconnect power.
2. Access the thermal cut-off by removing
the front panel. See Dryer Disassembly
Instructions, page 22.
3. Using an ohmmeter, check the continuity
across the thermal cut-off. See figures 11a
and 11b, page 14, for location.
4. If the ohmmeter indicates an open circuit,
perform the following:
ALL DRYERS: Replace both the thermal
cut-off and high limit thermostat. In addition,
check for blocked or improper exhaust
system, and, on electric dryers, for heat
element malfunction.
TEST #4d: Gas Valve (Gas Dryer)
1. Unplug dryer or disconnect power.
2. Access the gas valve by removing
the back panel. See Dryer Disassembly
Instructions, page 22.
3. Use an ohmmeter to determine if a
gas valve coil has malfunctioned. Remove
harness plugs. Measure resistance across
the terminals (see figure 12). Readings should
match those shown in the following chart;
if not, replace coils.
4. Disconnect the ignitor plug from the
burner. Using an ohmmeter, measure
the resistance across the ignitor’s 2-pin
connector. Resistance should be 50-500 Ω.
If resistance readings are outside the range
or open, replace the ignitor.
If resistance readings are within range, reconnect
the ignitor plug and continue to step 5.
5. Disconnect the wires going to the flame
sensor terminals. Using an ohmmeter, measure
across the two sensor terminals for continuity.
If there is continuity, reconnect the sensor
wires and continue to step 6.
If the reading is open, the flame sensor
needs replacing.
6. Reassemble back panel before
reconnecting power.
7. Plug in dryer or reconnect power.
8. Run a high-temp TIMED DRY cycle
of at least 2 minutes in duration.
9. Watch the ignitor for a couple of minutes
through the “peek window” in the side. If the
ignitor stays red hot and the gas does not come
out and ignite, the flame sensor needs replacing.
NOTE: If ignitor does not come on, line voltage
may not be present at the gas burner. The motor
centrifugal switch may be suspect.
Pin 1 – Black
Pin 2 – Blue
Pin 3 – White
Pin 4 – Blue
Pin 5 – White
Figure 12 - Measuring gas valve resistance.
Terminals
Resistance
in ohms
1 to 2 1400 ± 70
1 to 3 570 ± 28.5
4 to 5 1300 ± 65
GAS VA LV E RESISTANCE