Thermostat solenoid

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Bagger

New Member
Joined
Nov 28, 2014
Messages
5
Car
E350 CDI
Hello, The thermostat ( PN A642 200 16 45) on my 2010, E350 cdi bluemotion is stuck open. This particular PN has what appears to be a solenoid on top of thermostat housing, which I assume holds theromostat closed until desired temp is reached. My local parts shop sold me a replacement OEM part but without solenoid and cannot source identical part. My question, can I run replacement without solenoid. If not can anyone provide source (dealer last option).

Thank you in advance for your thoughts
Steve
 
I doubt it's a solenoid; more likely to be a temperature sensor of some kind. The thermostat holds itself closed until the desired temperature is reached, surely?
 
like this?
11.jpg
 
Grober, Thanks for the photo. Yes this is exactly how it looks

Cheers
Steve
 
Markjay, the part number you supplied is the item I received from local parts supplier which has no plug on housing top

Cheers
Steve
 
Thank you everyone for your replies. I have now found the part I need from AUTODOC, at very reasonable price.

Regards
Steve
 
That extra electrical connection is dealt with here.
https://translate.google.co.uk/tran...roidissement-et-lubrification.html&edit-text=

It refers to the ever increasing sophistication of cooling systems to provide finer control on engine warm up characteristiics essential in controlling emissions. This involves such fine control coolant devices such as variable output coolant pumps and a coolant thermostat with a built in heating element. My guess is therefore that the electrical connection on the termostat is for a heating element. :dk:
 
I figured it was a heating element for some obscure emissions shenanigans.
Why you'd want to heat the thermostat which would open it and cool the engine is a mystery.
 
I figured it was a heating element for some obscure emissions shenanigans.
Why you'd want to heat the thermostat which would open it and cool the engine is a mystery.

Because it is like 'thermostat' control is working in many places. There is a wax bar which is expanding when heat rises and then opening passage to cooler (and closing when cooling). Here electric heater element is warming the wax and opening thermostat in advance when ECU detetcts high power demand (before coolant itself has been warming).
 
It's like a tiny immersion heater which runs down through the centre of the actual thermostat.
 

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