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A/C hot, no condenser fans or compressor 99E300

1759 Views 26 Replies 4 Participants Last post by  55Benz
Hi Everyone. Last week while driving A/c air suddenly got hot. I purchase refrigerant and followed the instructions on resetting after the ec illuminated.
I hastily reset before writing down the code. Compressor come on but has occasionally for periods of less than a minute. I've tried to quickly add refrigerant while it's on with no success. Also according to my gauge the pressure on the low side quickly climbs when I try to add 134. This could be due to reading a value after the compressor has stopped running. Maybe? The pressure on low side according to my gauge was around 50psi. I let some gas out of the valve to lower it. I reduced it to about 10 psi. tried again to add when comp. briefly came on but no luck. Compressor only seems to come on when the car has not been running for 2 or more hours and I could get it or the aux fans to come on at all today. Fans turn freely by hand with no noted roughness. Fuses are all good in the engine compartment. I've run the diagnostics and will list their values below. Also I've been driving the car hoping the original fault will reappear but it has not and the ec light has not returned. Sorry I posted extra values. Thanks in advance for any help. It's hot here in Wilmington NC!
1 - 82
2 -78
3 -87
4 -87
5 -134
6 -94
7 -03
8 -82
9 -27
10-2.3
11-1.5
12-4.3
20-3.2
21-32
22-00
23-32
24-11.6
40-164
41-85
42-08
43-136
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1 - 2 of 27 Posts
The vibration/roar MIGHT be the cooling fans coming on at full blast or the compressor failing. In my '98 E320 when the compressor locked up there was a brief squeal followed by a short tug on the motor.
Check to see if the compressor is still turning.
Skippy
55Benz,
I have found that exercising the duo-valve will often fix it. By exercise I mean to raise both sides to max heat, let it get there, and then lower to max cold.
Of course you can take the valve apart and find some grunge to clean, but I'd try the exercise path to see if you can stabilize the left side (#3 on the readout).
Skippy
1 - 2 of 27 Posts
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