650 won't cool down to set temperature

That is correct, you have reached the thermostat set point. Does not matter C or F. Read the manual it will give you the limits:

The ideal refrigerator temperature is 35°F (1.6°C). You're not hugging the danger zone like you would be at 40°F (4.4°C), and you're distancing yourself sufficiently from 32°F (0°C) that you don't freeze half the stuff in your refrigerator.

Try these links:
At What Temperature Should My Refrigerator Be Set Tips from The Kitchn

What Are Normal Refrigerator and Freezer Temps eHow

What temperatures should keep my refrigerator and freezer set at

IVE SEN THIS ISSUE BEFORE

THE FACT THAT YOU CANT CHANGE THE SET COOL POINT ON THE UNIT BELOW 64 IS A SYMPTOM OF A DAMAGED CONTROL BOARD (SENTRY III), NOW THE UNIT CONTINUING TO COOL DOWN BELOW THE SET COOL POINT OF 64 AND GOING ALL THE WAY DOWN TO 55 IS MOST LIKELY THE RELAY.
I HAVE FIXED THIS EXACT SAME ISSUE BY REPLACING THE CONTROL BOARD AND RELAY ON THE UNIT.

It seems to me that you have a bad transistor, T14 or T13 to be precise. T14 most certainly is in short circuit or its companion T13 (T14 is a small signal NPN transistor whereas T13 is a small signal PNP transistor). I just fixed one with the same symptoms as yours. You should be able to measure T14 collector voltage against ground (metal chassis) and the reading must be very close to +15VDC. Also, measure T14 emitter voltage to ground and the reading must be very close to -15VDC. If any of those voltages is compromised, you will not be powering the amplifier's operational amplifiers (U4, U5, U6) right. Check T14 and T13 with your multimeter and replace them as needed. Also, keep in mind that after replacing any of those transistors you will be required to readjust the BIAS current for your amplifier's drivers, which by the way, is a very easy task to accomplish. You know your BIAS current is misadjusted when your output transistors get really hot even under no signal conditions or when your amplifier distorts at very low volume levels or on high frequencies amplifying. To adjust the BIAS current for channel 1's driver transistors, wait until the amplifier has cooled down, locate and adjust VR3 until you read 80 mV across R2. To adjust BIAS current for channel 2's driver transistors, locate VR6 and adjust it until you read 80mV across R106. You need to wait until the amplifier cools down to set BIAS current right, If the output transistors' heat sinks get hot before reaching proper BIAS current adjustments, wait until they cool down to average room temperature and retake BIAS current adjustment. Once both channels BIAS currents have been readjusted, apply a thin coat of thick nail polish to the sides of VR3 and VR6 to keep vibration from misadjusting BIAS currents again... T14 goes down under severe BIAS currents shifting and it just makes me wonder as to why BEHRINGER does not apply a setting substance to VR3 and VR6 so they do not shift under sever vibration conditions, after all, almost any major amplifier manufacturer in the world does it. Good luck!

I am thinking that perhaps the temperature sensor is reading wrong and therefore sending a message to the computer that the car is running too hot. This can happen, my VW presently reads 20 hotter on the guage than a heat gun records at the temp sensor location on the head. If you have access to a heat gun it might be a good idea to check out the actual temperature, but it probably won't hurt to change the sensor.

The other problem that occurs to me is the oil sending sensor. While a temperature sensor won't shut an engine down, the oil sender can. If it is reading a large drop in oil pressure it will shut the engine off. Since oil gets thinner as it gets hot, perhaps a defective sending unit is reading it as too low. Once the oil cools off, it would restart until the temperature gets too high again. I would think that upgrading to a heavier oil might cure the problem. I don't know what you are currently usung but certainly you could go to 10W30 or 10W40 without too much trouble, at least for a test. Hope this helps.

Hi,

From the Xerox Phaser 4500 Service Manual (here), the main problems could be one of:

• Warm-up failure - Fuser warm-up not complete within 110 seconds after
• starting.
• Cool-down error - Cool-down process not complete within 200 seconds.
• Low trouble temperature - The fuser temperature drops to the low trouble
• temperature (approximately current control temperature, minus
• approximately 25°C).
• High trouble temperature - The fuser temperature rises to the high trouble
• temperature (approximately current control temperature, plus
• approximately 35°C).
• STS circuit open
• STS failure - The heat rod remains on for at least 10 seconds after warm-
• up has completed

It could be that your fuser needs to be replaced, but as you can see that code relates to a couple of problems, so even replacing the Fuser might not fix the problem.

If it doesn't even do the warm up checks it is likely to be the fuser because the other components such as STS failure and cooldown won't have had a chance to run..

I believe it's showing the actual temperature that it's currently inside the refrigerator, not the temperature it's set at. At least that's how my sub zero works. You may need to clean the coils to get it to cool better.

Sufficient fluid in the reservoir does not necessarliy mean that the radiator is full. If you have fixed the radiator leak, let the engine cool down and the radiator will draw coolant in from the reservoir until it (the radiator) is full. Make sure the reservoir does not go dry while this is happening - and do not remove the radiator cap until after everything cools off completely.
There's no check valve in the cooling system, although the radiator cap does serve such a purpose when there's a reservoir attached.

yes you have 2 compressor. ona for fridge one for the freezer..

Is your thermometer in a glass of water? That's the way to get an accurate temperature reading. You may want to call an authorized servicer.

put you own thermometer inside and see if the temperature is the same as the digital thermometer. the light switch shouldn't have anything to do with the temp. another thing to check is see if the condenser fan (condenser is the metal coil on the outside) is running, and that the coil is clean. if the coil is dirty or the fan is not running then either clean the coil or check for voltage at the fan. if you have voltage to the fan and it doesn't run then you need to replace the fan. if you don't have voltage to the fan then you may have a deeper problem. hope this helps