I have a 1997 S320- the EC light remains on and, as a result the AC compressor does not go on. Is this because of low refrigerant level OR a bad relay? If it is a bad relay, which relay operates the compressor? Klima?

What is the EC light and how do you know that this light is related to a/c control ? There are a lot of components that combine to control the compressor, and if you have the Klima relay like I have on my 87, 260E, then there is a step by step process I have posted to test the compressor circuit.

ac still not working after ac conversion 87 300SDL

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Saumil S. Patel

See this one too - 210 chassis climate control problem

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Len
'59 220S Cabriolet-SOLD and living happily in Malta
'83 240D 351,500 miles original owner-SOLD
'88 560SL 41,000 miles - totaled and parted out
https://sites.google.com/site/mercedesstuff/home
'99 E300 turbo 227,500 miles
'03 SLK320 40,000 miles - gave to my daughter
'14 Smart electric coupe 28,500 miles
'14 Smart electric cabriolet 28,500 miles
'15 Smart electric coupe 28,000 miles

The EC switch turns off the compressor to revert the system to regular ventilation (no a/C). If the light stays on, your refrigerant charge is low, it is a failsafe mode.

Now, I just hope yourrefrigerant level is not low because of a leaking evaporator...

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A. Rosich
CL 500, 1998
S 500 L, 1998
E 320 T, 1995 [Sadly sold ]