Garland 7000 service manual Measure, Activity, Comment, Disconnect sensing element

Measure	Activity	Comment
M41	• Measure the resistance of coil temperature sensor resistor	Disconnect sensing element
	at 25º Celsius (77º F) resistor will read 1kOhm
	at 180º Celsius (356ºF) resistor will read 3,5kOhm
	• Resistor is higher on a higher temperature (PTC-resistor)
	• Replace sensor with a value less than 900Ohm
	• For a test: Short-out the sensor with a 1kOhm fixed RESISTER
M50	• Measure operational control or main power control switch with	Disconnect operational control
	potentiometer: Potentiometer is 10kOhm and linear	(Poti)
	• On level “0”: resistor = 0 Ohm
	• On maximum level resistance= 10kOhm
	• Resistor is proportional (linear) to swing angle
M60	• Measure temperature inside the case
	• Admissible ambient temperature: 0°C/32ºF to appr. 70°C/158ºF
	• Check point is on the CPU-circuit board
M100	• Check connection cable for serial operational control and
	CPU-circuit board
M101	• Change serial operational control
M200	• Check mains cable, perhaps one phase missing
	• Check the building fuses
M220	• Disconnect ST2 on CPU-circuit board and measure resistance
	between brown and blue,
	Measured value: 200Ohm < R < 2kOhm
	• Replace rectifier circuit board
M240	• Use suitable pan material
	• Test with a pan with a diameter of 24cm (4.75”)
M241	• Disconnect mains power supply
	• Visually inspect : blackened cables, components or strip
	conductors?
	• Transistor module: measure internal diodes (UF = 0.4V)
	• Rectifier: measure internal diodes (UF = 0.5V)
	• Control trafo: measure electric voltage
	• Check power supply CPU-print +24V
	CPU-circuit board ST1/1 and ST1/4 (24V +/- 1V)
M251	• Check power switch on operational control

Part # 4526029 (02/22/11) Page 13