Sharp R-1880LS Service Manual page 26

R-1880LS/LST
PROCEDURE
LETTER
M HOOD FAN MOTOR TEST
1. Disconnect the power supply cord, and then remove outer case.
. Open the door and block it open.
3. Discharge high voltage capacitor.
4. If the motor does not turn, touch the Vent button once (set hood fan motor power "HIGH") and check voltage
between pins "1" and "" (Blue and Black wires) of the 6 pin connector. If 10 Volts appear and the hood
capacitor is good, replace the hood fan assembly. If 10 Volts does not appear, check the motor circuit. The
resistance values of motor terminals are as follows:
HOOD
FAN
CAPACITOR
5. Reconnect all leads removed from components during testing.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
N DAMPER MOTOR TEST
1. Disconnect the power supply cord, and then remove outer case.
. Open the door and block it open.
3. Discharge high voltage capacitor.
4. When the power cord is plugged into the wall receptacle and 10 volts A.C. is supplied to the damper motor,
the motor operates until the damper is opened and the damper switch closes. Then the damper motor stops
operation.
5. If the damper motor does not operate, check for A.C. voltage with a voltmeter at the motor.
6. Disconnect the power cord from the wall receptacle.
7. Disconnect the wire leads of motor and connect the meter leads to the wire leads of main wire harness.
8. Re-connect the power cord into the wall receptacle.
If 10 volts A.C. is indicated at the wire leads, replace the motor and if 10 volts A.C. is not indicated, check
the wire harness and control unit.
9. Run the oven and check all functions.
O HEATING ELEMENT TEST
1. Disconnect the power supply cord, and then remove outer case.
. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Make sure the heating element is fully cooled and test as follows;
a. Disconnect wire leads and measure the resistance with an ohmmeter. On the R x 1 scale, the resistance between
the heating element terminals should be approximately 10
b. Disconnect wire leads and measure the insulation resistance with 500V - 100M ohm insulation resistance
meter. The insulation resistance between heating element terminal and cavity should be more than 0.5M
5. Reconnect all leads removed from components during testing.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
TEST PROCEDURES
YLW
4
32
45 20
5
RED
COMPONENT TEST
BLU
Resistance between;
1
BLU (1) AND
BLK (2) AND
BLU (1) AND
BLK (2) AND WHT (3) = 20 ohm
WHT (3) AND
2
BLK
3
WHT
6-PIN CONNECTOR
OF HOOD FAN MOTOR
.
Ω
6
YLW (4) = 0 ohm (Shorted)
YLW (4) = 32 ohm
BLK (2) = 32 ohm
RED (5) = 45 ohm
BLU BLK WHT
1 2 3
4 5
YLW RED
.
Ω