Bosch HBL 73 Service Manual page 42

Tuesday, June 18, 2002
BOSCH 700 SERIES:
ELETTRODOMESTICI
SERVICE INSTRUCTIONS FOR OVEN TESTING AND BASIC TROUBLESHOOTING
VIA CHECCHI 98
I 21013 GALLARATE
ITALY
F112 LOWER OVEN 650°F RUNAWAY
CONDITION
F113 UPPER OR SINGLE OVEN 950°F
RUNAWAY CONDITION
F114 LOWER OVEN 950°F RUNAWAY
CONDITION
F121 STUCK KEYBOARD KEY
F123 KEYBOARD DISCONNECTED
1. Allow oven to cool to <650°F before turning power on.
2. Check P24 connector on the Power Board.
3. Unplug the sensor connector and check lower sensor resistance (approximately
1080 ohms at room temperature with connector removed).
4. Check wiring to heating element. If OK, replace Power Board.
1. Check P4 connector on the Power Board.
2. Unplug the upper (or single) oven sensor connector and check sensor resistance
(approximately 1080 ohms at room temperature with connector removed).
3. Check wiring to heating element. If OK, replace Power Board.
1. Check P24 connector on the Power Board.
2. Unplug the sensor connector and check lower sensor resistance (approximately
1080 ohms at room temperature with connector removed).
3. Check wiring to heating element. If OK, replace Power Board.
1. Check all connections between the display head (P5) and the keyboard (J1).
2. Make sure that there are no objects in close proximity to the front and back sides
of the keypads.
3. Replace Display Board or keyboard or both.
1. Check all connections between keyboard (J1) and Display Board (P5).
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